FPA 907/D 77.O01 EPA-7-IA-Des Moines-
Dallot, Polk, Warren-AWTMP-77
DRAFT
ENVIRONMENTAL IMPACT STATEMENT
for
DES MOINES
208 AREAWIDE WASTE TREATMENT
MANAGEMENT PLAN
e..s
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION VII - KANSAS CITY, MISSOURI
MARCH 1977
-------
D Sr 4
UNITED STATES ENVIRONMENTAL PROTECTION
r 1 iiON IX
4 4 pRO1 C
REGION VII I
735 BALTIMORE 1 2 3
KANSAS CITY, MISSOURI 64108
April 6, 1977
TO: ALL INTERESTED GOVERNMENT AGENCIES, ORGANIZATIONS, AND CITIZENS
Enclosed with this notice is a copy of the Draft Environmental Impact
Statement (EIS) for the Des Moines Metropolitan Areawide Waste Treatment
Management Plan. This document is submitted for your review and comment
pursuant to Section l02(2)(c) of the National Environmental Policy Act of
1969 (Public Law 91-190). All comments submitted to this agency on the
draft statement and the Environmental Protection Agency’s (EPA) responses
will be incorporated into the final statement.
The Central Iowa Regional Association of Local Governments (CIRALG) has
prepared the plan through funding by the EPA. The plan is intended to be
a management document identifying the waste treatment problems and their
effects upon water quality in the greater Des Moines area. It sets forth
an effective management program to alleviate these problems and it is
ultimately intended to achieve and maintain a quality of water which can
provide for all necessary uses within the Des Moines Metropolitan area.
The Draft EIS is EPA’s analysis of the environmental impacts of the plan
prepared by CIRALG.
Comments should be submitted to this office within 45 days of the date the
President’s Council on Environmental Quality (CEQ) publishes notice of the
EIS in the Federal Register. It is expected CEQ’s notice will be published
on or about April 15, 1977. Additional copies of this statement are avail-
able for review in the EPA, Region VII library, the Des Moines Public
Library, and other libraries in the Des Moines area. Please direct your
comments to the U.S. Environmental Protection Agency at the address given
above.
We appreciate the time and effort spent in reviewing this statement.
Sincerely yours,
r / Charles V. Wright
Acting Regional Administrator
-------
E D
17-
001
EPA-7-IA-Des Moines -
Dallas, Polk, Warren-AWTMP-77-005
DRAFT
ENVIRONMENTAL IMPACT STATEMENT
for the
DES MOINES 208 AREAWIDE WASTE
TREATMENT MANAGEMENT PLAN
DES MOINES METROPOLITAN AREA,
DALLAS, POLK, AND WARREN COUNTIES, IOWA
prepared by
U.S. ENVIRONMENTAL PROTECTION AGENCY
REGION VII
KANSAS CITY, MISSOURI
information furnished by
CENTRAL IOWA REGIONAL ASSOCIATION OF LOCAL GOVERNMENTS
with the assistance of
KIRKHAM, MICHAEL CONSORTIUM
US EPA
irters and Chemical Libraries
West Bldg Room 3340
M i:code 34041
‘O1 Crnstjt , Ave NW
/ashington DC 20004
202-566-0556
Approved by:
C L -
Charles V. wright
Acting Regional Administrator
‘iaterja/
-------
Summary
AREAWIDE WASTE TREATMENT MANAGEMENT
PLAN, DES MOINES, IOWA
(X) Draft ( ) Final
Responsible Office : U.S. Environmental Protection Agency, Region VII,
1735 Baltimore, Kansas City, Missouri 64108, telephone 816-374-2921.
1. Type of Action : (X) Administrative ( ) Legislative
2. Description of Action : The Central Iowa Regional Association of
Local Governments (CIRALG) has prepared the Des Moines Metropolitan
Areawide Waste Treatment Management Plan. Several municipalities
and three counties are represented by CIRALG. The Des Moines
Metropolitan Sewer Planning Policy Committee was for the most part
responsible for the review and advisory functions required in
producing the plan.
The plan has been developed pursuant to Section 208 of the Federal
Water Pollution Control Act Amendments of 1972 (Public Law 92-500).
The U.S. Environmental Protection Agency (EPA) has determined that
its approval of the Des Moines plan is a major Federal action with
the potential of affecting the quality of the human environment.
As required under Section 102(2)(c) of the National Environmental
Policy Act of 1969 (Public Law 91-190), EPA must prepare an environ-
mental impact statement regarding its approval of the plan.
The proposed plan includes structural and nonstructural programs for
the control of point, intermittent point and nonpoint pollution
sources. Proposed point source actions for the central urban area
include the construction of a wastewater collection system with
13 flow-equalization basins for the control of maximum infiltration!
inflow quantities and the construction of a new sewage treatment
facility immediately east of the existing Des Moines wastewater
treatment plant. To meet the required degree of secondary treatment,
the new plant is proposed to have an activated biofilter unit
followed by supplemental aeration. The flow following the first
stage biological unit is proposed to receive split treatment, wherein
a portion of the flow will receive tertiary treatment to meet ammonia
standards. Dewatered anaerobic sludge will be applied to agricultural
land or disposed at the Metropolitan landfill operation.
-------
The plan proposes that collection systems and controlled discharge
lagoons be constructed for some outlying communities. The plan
also recommends that some other communities upgrade their existing
lagoon systems to provide for adequately controlled discharges.
For another community, the plan recommends either building a new
mechanical plant or a modified controlled discharge lagoon. It
also suggests that one other community upgrade its existing
mechanical lagoon system and another construct a collection system
and mechanical treatment facility.
Proposed intermittent point source controls for the Integrated
Community Area include segregation of combined sewers and the
installation of flow separators at selected combined and storm
sewer discharge points. Segregation of combined sewers actually
occurs as part of the proposed interceptor system. It has been
recommended that a new lift station, force main and outfall sewer
be constructed to collect the wastewater from northwest Des Moines,
Johnston, Urbandale, Beaver Creek, Camp Dodge, Lovington, West Ankeny,
and Saylor Township (an unincorporated area). The wastewater from
these areas will then be segregated from the Westside Interceptor
and transported beyond the combined sewer overflow area. In
addition to segregation, flow separators to be located at selected
combined sewer overflows and storm sewer discharge points are also
recommended as intermittent point source controls.
The plan recommends nonpoint sources of pollution be controlled by
nonstructural programs. These actions include reducing nonpoint
source pollution from cropland, construction sites, and unincorporated
areas. For additional control of cropland runoff, the plan recommends
a subsidy program be implemented to increase the cost-sharing for
the construction of terraces and grade stabilization structures.
Passage and enforcement of ordinances aimed at controlling pollution
from construction sites are also recommended. Local planning
entities are expected to help effect reductions in urban development.
3. Environmental Impacts : The proposed plan will significantly
improve the water quality in the area and eliminate water quality
standard violations in the area’s receiving streams under both
critical wet and dry weather conditions.
Point source controls are expected to have a major impact on surface
water quality, but have very little effect on water quantity. The
proposed plan requires the abandonment of many inefficient treatment
plants which should improve the water quality of the receiving
streams in the area (especially Des Moines River, Beaver Creek,
Walnut Creek, and Raccoon River). Dissolved oxygen levels should
increase, while fecal coliform and ammonia-nitrogen levels are
expected to decrease.
II
-------
Intermittent point source controls will require separated sewage
to be removed from the combined sewer system. This should greatly
improve the quality of the Des Moines River by reducing its
pollution loading.
The nonpoint source control programs are expected to result in
significantly decreased water pollution in all receiving streams.
Coordinated land use control programs should have an overall benefi-
cial impact on the environment. Open space programs and development
controls would help protect environmentally sensitive areas;
including flood plains known to be sources of potable water, surface
waters, wetlands, 100-year flood plains and flood retention areas,
ground water recharge areas, prime agricultural lands, and public
outdoor recreation areas.
The proposed plan should have no primary impact on air quality in
the area. It does not propose that sludge be incinerated. Air
emissions from the treatment facilities should be minimal.
The three source control programs should eliminate all water quality
standard violations in the area’s major streams and create a signif-
icant beneficial impact on the environment. Impacts on archeological
and historic sites, energy usage, and economics are not expected to
be significant.
4. Adverse Environmental Effects : During the construction of the
proposed collection and treatment facilities and equalization basins,
locally disruptive fugitive dust will be emitted. The severity of
dust emissions will be dependent upon weather conditions. Other
temporary impacts resulting from construction activities will be the
disruption and relocation of wildlife, augmented construction noise
levels,djsturbance of existing vegetation, and disruption of
existing land uses; e.g., traffic and other urban activities.
An adverse impact associated with the operation of treatment facilities
is the generation of sludge. The methods used to dispose of and/or
apply the sludge will determine the degree and kinds of impacts which
may result.
5. Alternatives : General alternatives of the plan include:
Modification of the existing management plan, resulting in different
methods of implementing the programs herein described; alternate
methods of wastewater treatment; alternate sludge disposal and
treatment methodology; alternate subplans for minimizing point,
intermittent point and nonpoint pollution discharges.
The alternate areawide plans presented in this statement are listed
below:
III
-------
a. Expanding the existing Des Moines treatment plant,
segregation of combined sewers, promotion of cropland runoff
control options and possible increases in street sweeping.
b. Same as (a), with the passage and enforcement of ordinances
for controlling erosion and sedimentation from construction sites
and reduction in the urban development or agricultural land.
c. Expanding the existing Des Moines plant, segregation of
combined sewers, flow separators for combined sewer overflows and
strategic storm sewer discharges, promotion of cropland runoff
control options and possible increases in street sweeping.
d. Same as (c), with the passage and enforcement of ordinances
for the control of erosion and sediment from construction sites and
reductions in the urban development of agricultural land.
e. Constructing a new areawide wastewater treatment plant,
segregating combined sewers, promotion of cropland runoff control
options, and possible increases in street sweeping.
f. Same as (e), with the passage and enforcement of ordinances
for controlling erosion and sedimentation from construction sites
and reducing urban development of agricultural land.
g. Constructing a new areawide wastewater treatment plant,
segregation of combined sewers, flow separators for combined sewer
overflows and strategic storm sewer discharges, promoting cropland
runoff control options and possible increases in street sweeping.
h. Same as (g), with the passage and enforcement of ordinances
for controlling erosion and sedimentation from construction sites
and reductions in urban development of agricultural land.
6. Date Available to the Council on Environmental Quality and to
the Public :
Distribution list is attached
‘V
-------
DISTRIBUTION LIST
FEDERAL AGENCIES
Council on Environmental Quality
U.S. Army Corps of Engineers
U.S. Department of Agriculture
Soil Conservation Service
U.S. Department of Commerce
U.S. Department of Health, Education and Welfare
U.S. Department of Housing and Urban Development
U.S. Department of the Interior
Fish and Wildlife Service
Bureau of Land Management
Bureau of Outdoor Recreation
National Park Service
Geological Survey
U.S. Department of Transportation
Federal Highway Administration
Coast Guard
Federal Aviation Administration
Upper Mississippi River Basin Comission
MEMBERS OF CONGRESS
Neal Smith, U.S. House of Representatives
John C. Culver, U.S. Senate
Richard C. Clark, U.S. Senate
STATE
Iowa “A-95” Coordinator, Governor’s Office
Iowa Department of Environmental Quality
State Library Commission of Iowa
State Historical Department of Iowa
Office of the State Archaeologist
LOCAL AND REGIONAL
City of Alleman
City of Altoona
City of Ankeny
City of Bondurant
City of Carlisle
City of Clive
City of Cunining
Dallas County v
-------
LOCAL AND REOIONAL CONT’D
City of Des Moines
City of Elkhart
City of Granger
City of Grimes
City of Hartford
City of Johnston
City of Mitcheilville
City of Norwalk
City of Pleasant Hill
City of Polk City
Polk County
City of Runnells
City of Spring Hill
City of Urbandale
Warren County
City of Waukee
City of West Des Moines
City of Windsor Heights
Central Iowa Regional Association of Local Governments
Health Planning Council of Central Iowa
INTERESTED INDIVIOUI’LS
Carrol Blorne, Dallas County Farm Bureau
11. James Hall, Jr., Pioneer Hi—Bred International, Inc.
David H. Comann, Shive—Hattery and Associat€s
R.L. Goodson, Polk—Des Moines Taxpayers
Leo Johnson, Director, Department of Public Works, fles Moines
Gladys Burkhead, Des IVoines Council of PTA’s
Ray Henely, Associated General Contractors of Iowa
Dan Cosgriff, Home Builders Association of Greater Des £ ‘oines
Mark Knudsen, South Des F•loines Chamber of Commerce
Jess Lewis, American Society of Landscape Architects
Richard E. Gardner, A erican Society of Landscape Architects
Fred Lock, United rederal Savings and Loan Co., Des oines
Torn L. Robinson, Iowa Limestone Producers Assoc. , Inc.
Ken McNichols, Iowa Limestone Producers, Assoc., Inc.
Ray Stephens, Iowa Council of Area School Boards
Jack Colvig, Des Moines, Metropolitan Sewer Planning Citizen’s Advisory
Committee
Marilyn Staples, Des Moines, Metropolitan Sewer Planning Citizen’s
Advisory Committee
Robert Wilkens, Runnells, Metropolitan Sewer Planning Citizen’s Advisory
Committee
Dorothy Hurst, West Des Moines, Metropolitan Sewer Planning Citizen’s
Advisory Committee
v
-------
INTERESTED INDIVIDUALS CONT’D
Lee Daliager, Des Moines, Metropolitan Sewer Planning Citizen’s
Advisory Committee
Lee Minear, West Des Moines, Metropolitan Sewer Planning Citizen’s
Advisory Committee
Dave Love, Northwestern Bell Telephone Company
Bob Ziesman, Iowa Realty Company, Inc.
Ron Dichson, Iowa—Des Moines National Bank
John C. McClellard, Asphalt Paving Association of Iowa
Casey P. Shanahan, Iowa Taxpayers Association
Lester 1. Phodes, Iowa Soybeans Association
Jack H. Wesenberg, Executive Vice President, Greater Des Moines
Chamber of Commerce
Ralph Schleaker, Vice President, Iowa Power and Light Company
Edith Crist, American Association of University Women
Vincent Bobenhouse, U.S. Power Squadron, Des Moines
Thomas D. McMillan, Executive Director, American Road Builders
Association of Iowa
Joe Blodgett, Executive Secretary, Des Moines Construction, Inc.
George Hampel, Jr., Executive Director, Des Moines Educational Assoc.
Earl 1. Ring, Executive Vice President, Iowa Association of
Electric Coops
Donald E. Krlst, Executive Vice President, Iowa Assoc. of Mutual
Insurance Agents
M. J. Knutson, Executive Director, Iowa Concrete Paving Assoc.
Richard Maim, Atty., Dickinson, Throckmorton, Parker, Munnheimer
and Raife
R. M. Oothout, Iowa Power and Light Company
Dennis Van Lien, Des Moines Advisory Committee on Environmental Quality
Stan Moore, Des Moines Power Squadron
Harlan W. Rigby, Polk County Farm Bureau
John W. Judge, American Federal Savings and Loan Association
Wayne J. Hennesy, Society of Real Estate Appraisers
George Green, Crown Redi Mix
Dr. Robert S hu1tes, Broadlaws Polk County Hospital
Lester L. Rhodes, Iowa Soybean Association
Miriam Bond, Government Publications Department, Iowa State University
Colonel Wayne Daffron, National Guard of Iowa
Julius S. Conner, M. D., Director of Public Health, Des Moines
Jerry Pecinovsky, City Manager’s Office, Des Moines
INTERESTED GROUPS
Iowa Confederation of Environmental Organizations
Iowa Conservation Education Council, Inc.
Southeast Polk High School Ecology Club
American Institute of Architects
vii
-------
INTERESTED GROUPS CONT’D
Iowa Association of Municipal Utilities
Iowa Farmers Union
League of Women Voters
National Association of Regional Councils
Izaak Walton League, Ankeny Chapter
League of Women Voters
“D ing° Darling Foundation, Inc.
National Park Producers Council
PTA of Iowa
West Des Moines Chamber of Commerce
Rotary Club of Des Moines
Ankeny Chamber of Commerce
Warren County Farm Bureau
Des Moines Women’s Clubs
Kiwanis Downtown Club
Lions Club of Greater Des Moines
Girl Scouts of America
Izaak Walton League of America, Iowa Division
Boy Scouts 0 f America
Des Moines Minority Contractor Association
Executive’s Association, Inc.
Home Builders Association
Industries Council of Des Moines
Iowa Association of Life Underwriters
Iowa Association of Secondary School Principals
Iowa Bankers Association
Iowa Ornithologists’ Union
Sierra Club, Iowa Chapter
Nature Conservancy
State Preserves Board
Iowa Commercial Fisheries Association
Ducks Unlimited
Wildlife Society
Citizens for Environmental Action
Iowa Wildlife Federation, Inc.
viii
-------
Page
SUMMARY
DISTRIBUTION LIST v
CHAPTER I - BACKGROUND
Introduction
Brief Description of Structural and Non-structural
Actions Proposed
Brief Summary of Water Quality and Water
Quantity Problems in the Study Area
Total Anticipated Cost
CHAPTER II - THE ENVIRONMENT WITHOUT
PROPOSED ACTION
Introduction
Climate
Topography
Geology
Soils
Hydrology
Water Quality and Quantity Problems
Water Uses
Water Quality Management
Biology
Economic and Population Trends
Land Use
Environmentally Sensitive Areas
Aesthetics
Noise
Radioactieity
CHAPTER III - ALTERNATIVES
General Analytical Approach to the
Development of Alternatives . .
Continuous Point Source Alternatives
Intermittent Point Source Alternatives
Non-point Source Alternatives . . .
Areawide Plans
Selection of Preferred Technical Areawide Plan
III—’
1 1 1—1
1 1 1—1
111—9
111—12
111-14
111—21
TABLE OF CONTENTS
I—i
I—i
I—i
1-4
1—5
Il—i
h—i
11—2
11—3
11—6
11-10
11—13
11—27
11—31
11-34
11—37
11—42
11—44
11—56
11—61
11—61
11—62
THE
Alternate Management Plans
111—22
-------
TABLE OF CONTENTS - Continued
Page
CHAPTER V - ENVIRONMENTAL EFFECTS OF THE
PROPOSED PLAN
General Approach to Assessment of
Environmental Effects
Impacts on Water
Impacts on Air
Impacts on Land Use
Biological Impacts
Impact on Environmentally Sensitive Areas
Environmental Impact of Facility Plans in
Outlying Areas
Energy Requirements
Impact on Historic/Archaeologic Sites
Economic Impact
Social Impact
Economic and Social Impacts of Alternate Plans
CHAPTER VI - ADVERSE IMPACTS WHICH CANNOT BE
AVOIDED SHOULD THE PLAN BE IMPLEMENTED AND
STEPS TO MINIMIZE HARM TO THE ENVIRONMENT
Air Quality Impacts
Impact on Land and Land Use
Disruption by Sewer Alignments
Construction of Facilities over Surficial Aquifers
and Floodplain Areas
CHAPTER VII - RELATIONSHIP BETWEEN LOCAL SHORT-TERM
USERS OF MAN t S ENVIRONMENT AND THE MAINTENANCE
OF LONG-TERM PRODUCTIVITY VII-1
CHAPTER VIII - IRREVERSIBLE AND IRRETRIEVABLE COM-
MITMENTS OF RESOURCES RESULTING FROM THE PLAN . . . VIII-1
LITERATURE CITED LC-1
APPENDIX A - CHARACTERISTICS OF SOILS IN MAJOR SOIL GROUPS
- INTERIM LIST OF ENDANGERED SPECIES IN IOWA
CHAPTER IV - DESCRIPTION OF PROPOSED PLAN
General Description
Description of Areawide Sub-systems
Management Plan
IV- 1
IV- 1
IV- 2
IV- 5
V —i
V-i
V-i
V-8
V-9
V-15
V-18
V-21
V—37
V-37
V-38
V-59
• . V-70
VI-1
• . • VI-1
• • . . VI-1
• . • • VI-2
VI- 3
-------
INDEX TO TABLES
Table Page
1 1-1 Mean, Maximum and Minimum Monthly
Temperature 11-4
11-2 Mean Monthly Values of Precipitation 11-5
11-3 Location of IDEQ Reported Sampling Stations. . 11-16
11-4 Summer Water Quality of the Des Moines River 11-18
11-5 Winter Water Quality of the Des Moines River . 11-19
11-6 Representative Partial Analyses of Water from
Bedrock Formations 11-25
11-7 Representative Partial Analyses of Water from
Unconsolidated Aquifers 11-26
11-8 Average Daily Water Consumption - 1975 and
Projected Daily Water Consumption - 2000 . 11-32
11-9 Future Employment by Major Employment
Category in the 208 Area 11-43
11—10 Land Use — 1975 11—47
1 1-11 Anticipated Population Trends 11-50
11-12 Status of Land Use Planning . . 11-52
1 1 1-1 Comparison of Areawide Plans . . 111-16
V-i Percent of Personal Income Spent on Sewage Treatment. V-43
V-2 Anticipated Changes in Age Groupings of Population . . V-60
INDEX TO PLATES
Plate Page
Il-i Drainage Basins and Sub-areas 11-7
11-2 Stratigraphic Column of Iowa 11-9
11—3 Land Use — 1975 11—45
11-4 Major Environmentally Sensitive Areas 11-59
11—5 Land Capability for Agricultural Use 11-60
V-i Preliminary Intensity Development Pattern V-li
V-2 Sewer Back-ups V-64
-------
CHAPTER I - BACKGROUND
Introduction
The Des Moines Metropolitan Areawide Waste Treatment Management
Plan was prepared by the Central Iowa Regional Association of Local
Governments (CIRALG) with the assistance of the Kirkham, Michael and
Associates Consortium. Cities and Counties represented by CIRALG were
Alleman, Altoona, Ankeny, Bondurant, Carlisle, Clive, Cumming, Dallas
County, Des Moines, Elkhart, Granger, Grimes, Hartford, Johnston, Mitchell-
yule, Norwalk, Pleasant Hill, Polk City, Polk County, Runnells, Spring Hill,
Urbandale, Warren County, Waukee, West Des Moines and Windsor Heights.
Throughout the planning process the Des Moines Metropolitan Sewer
Planning Policy Committee (itself served by six committees and subcommit-
tees) served the major review and advisory role. The Committee consisted of
voting members from 23 of the units of government listed above and non-
voting members of the remaining three. The Policy Committee gave its final
endorsement to the proposed plan by the unanimous vote of those present on
January 27, 1977. The six committees and subcommittees had local citizen
representatives as well as resident local, state and federal professional and
governmental representatives.
Brief Description of Structural
and Non-structural Actions Proposed
The proposed areawide plan includes structural and non-structural
actions for the control of point, intermittent point and non-point sources of
pollution. The proposed structural actions may be classified as Best
Practicable Waste Treatment Technology (BPWTT) and the proposed non-
structural actions may be classified as Best Management Practices (BMP).
-------
1—2
Proposed point source actions for the central urban area include the
construction of a wastewater collection system with 13 flow-equalization
basins for the control of maximum infiltration/inflow quantities and the
construction of a new treatment facility immediately east of the existing Des
Moines wastewater treatment plant. It is proposed that the required degree
of secondary treatment at the new plant be achieved by utilizing an activated
bio-filter (ABF) unit followed by a second stage activated sludge system foq
nitrification. Split flow treatment would be utilized by using the first stage
biological unit (ABF tower) by itself or in combination with the activated
sludge units. Anaerobic sludge disposal followed by solids dewateririg with
disposal on agricultural land or at the Metro landfill is proposed.
One PL 92-500, Section 201 (facilities planning) project is underway for
the City of Runnells. The City of Norwalk is prepared to proceed with
facilities planning, pending the completion and final outcome of the 208
areawide plan. Altoona, Ankeny, Bondurant, Granger, Grimes, Mitcheliville,
Waukee and the Southside sub-system of Des Moines have received notice to
proceed from EPA on Section 201 sewer system evaluation surveys (SSES).
Approximately six communities and sub-systems have so far been found non-
excessive in infiltration, and approximately 12 other communities and sub-
systems have received EPA and DEQ concurrence in the infiltration/inflow
analyses and are at various stages of progress in initiating SSES studies.
National Pollutant Discharge Elimination System permits are required
for the proposed areawide wastewater treatment plant, for all facilities in
outlying communities which discharge treated effluent (see paragraphs below)
and for all industries discharging directly to receiving streams.
Thirteen communities have been classified as “outlying communities”
due to the cost-effectiveness associated with including them in the Integrated
Community Area (ICA). For the following communities it is recommended
that collection systems and controlled discharge lagoons be constructed:
-------
1—3
1. Alleman
2. Cumming
3. Hartford
4. Spring Hill
The following communities should upgrade existing lagoon systems to provide
for controlled discharge:
1. Carlisle
2. Elkhart
3. Granger
4. Norwalk
5. Polk City
Mitcheilvifle should either build a new mechanical plant or a modified
controlled discharge lagoon. Grimes should upgrade its existing mechanical-
lagoon treatment system and Runnells should construct a collection system
and mechanical treatment plant. Waukee should upgrade its existing aerated
lagoon system and add rock filters for effluent polishing.
Proposed intermittent point-source controls for the ICA include
segregation of combined sewers and the installation of flow separators at
selected combined and storm sewer discharge points. Segregation of
combined sewers actually occurs as part of the proposed interceptor system
in which a new lift station, force main and outfall sewer should be
constructed to collect the wastewater from the northwest Des Moines area,
Johnston, Urbandale, Beaver Creek, Camp Dodge, Lovington, West Ankeny
and parts of Saylor Township. The wastewater from these areas would then
be segregated from the Westside Interceptor and transported around the
combined sewer overflow area. In addition to segregation, flow separators
located at selected combined sewer overflows and storm sewer discharge
points are also recommended as intermittent-point source controls.
-------
1-4
Non-structural actions contained within the plan are primarily for non-
point source pollution control. The non-structural items proposed include
programs for reducing non-point source pollution from cropland, construction
sites and unincorporated areas. For additional reduction of cropland source
pollution, an increase in the subsidized cost-sharing program for the
construction of terraces and grade stabilization structures has been recom-
mended. The passage and enforcement of ordinances for the control of
pollution from construction sites has also been recommended. Reductions in
the urban development of unincorporated areas would be achieved through
local governmental land use control programs.
Brief Summary of Water Quality and
Water Quantity Problems in the Study Area
Iowa water quality standards are violated periodically in rivers and
streams in the study area. These occur primarily in winter or during low-flow
conditions and consist of violations of coliform bacteria levels, dissolved
oxygen and ammonia downstream of municipalities which discharge waste-
water. Ammonia violations are the most frequent.
Pesticides, such as dieldrin, DDT and its breakdown products, have been
detected in higher than recommended concentrations in study area streams.
Turbidity during periods of heavy storm runoff is high in area rivers and
streams.
Water temperature in the Des Moines River downstream of the City of
Des Moines is a potential problem, but adequate data on source and extent
are lacking at the present time.
Concentrations of phosphorus and nitrogen compounds are high enough
in area rivers and streams to cause significant eutrophication, although other
factors often limit eutrophication - such as temperature and turbidity.
-------
1—5
Periodic flooding occurs on area rivers and streams, particularly Beaver
Creek, Walnut Creek, Raccoon River, Middle River, ower Des Moines River
and Four Mile Creek.
Total Anticipated Cost
The estimated total areawide plan construction cost is approximately
$142 million. Approximately $108 million will be required for the Integrated
Community Area (ICA) point-source control construction cost and approxi-
mately $1.3 million for the ICA intermittent point-source control construc-
tion cost. The construction of new wastewater treatment facilities and
improvement of existing facilities for outlying communities will require $5
million. Federal and State grants for point-source control are estimated to
be $85 million and $6 million, respectively. Presently, intermittent point—
source controls are not eligible for EPA grants.* The estimated local share
of the total construction cost for intermittent and point-source control is $24
million of which approximately $1 million is for the outlying communities and
the remainder for the ICA. An additional $8 million will be required for
collection systems.
Approximately $27.5 million would be required for non-point source
control construction costs. Erosion and sediment control at construction sites
has been estimated to cost $2.5 million. Construction costs for terraces and
grade stabilization structures have been estimated to cost a total of
approximately $50 million; assuming continued state cost-sharing at 50
percent, the local cost would be $25 million. Presently, non-point source
controls are not eligible for EPA grants.*
*Other federal programs are (or may be) able to provide assistance for these
proposals.
-------
Il—i
CHAPTER II- THE ENVIRONMENT WITHOUT THE PROPOSED ACTION
Introduction
The Des Moines 208 study area contains approximately 800 square miles
and includes most of Polk County, parts of Dallas and Warren Counties and a
very small part of Jasper County. The total 1975 population was
approximately 315,000. The City of Des Moines (population about 200,000) is
surrounded by an inner tier of 12 municipalities and an outer tier of 10
freestanding rural communities. In addition there are several unincorporated
areas that are primarily residential and have only minimal community
facilities. These communities lie close to the urban area.
The study area falls almost entirely within the Des Moines River Basin;
a small area in the northeast corner drains to the Skunk River. Twelve
tributary streams in the study area flow to the Des Moines River, the largest
being the Raccoon River. A large fraction of the potable water supply for
the study area is taken indirectly from the lower Raccoon River via intake
galleries in the alluvial aquifer lying along the river. Three other municipal
water systems are located in the Raccoon River valley (West Des Moines, Fox
Creek Water Co., and Southwest Polk Water Co.) as well as a reservoir to
supplement flows in the River during low—flow conditions (Dale Maffitt
Reservoir).
The study area is affected by two major dams on the Des Moines River,
one forming the Saylorville Reservoir and the other forming Lake Red Rock.
The latter is outside the study area, but its flood pool reaches into the
southeast portion, and it receives nearly all the natural drainage from the
study area. Big Creek Lake, created by a diversion dam to protect Polk City
from flooding by Saylorville Lake, lies directly east of Saylorville Reservoir.
-------
11—2
Nearly 70 percent of the total land area is used for agriculture and
approximately 15 percent for urban uses. Fewer than 2,000 persons are
employed in agriculture (approximately 1.5 percent of the total population).
Approximately 33 percent of the work force is employed in services and
government, 23 percent in trade and 19 percent in manufacturing.
The highly productive agricultural land in the study area is its most
valuable natural resource and forms the basis of a large portion of the area’s
economic development. This land is also the source of troublesome water
pollutants - particularly suspended and settleable solids, nutrients, pesticides
and pesticide residues. Cost-effective control of these pollutants is one of
the major challenges of this 208 study. Other major water quality problem
areas are the economical collection and treatment of sanitary sewage from
the urbanized area, the control and management of combined sewer
overflows, and the control and management of stormwater runoff in
urbanized and developing areas.
Climate
The climate of the central Iowa region is strongly seasonal due to its
interior location on the continent. During winters, large masses of cold, dry
air move in from the polar region; during summers warm, moist air from the
Gulf of Mexico dominates the region. Occasionally, air masses from the
Pacific Ocean move into central Iowa producing relatively mild, dry weather.
Hot, dry winds from the southwestern desert region of the country
occasionally bring desicating conditions to the area.
Temperature
The mean annual temperature for the City of Des Moines is 51 degrees
fahrenheit (11 celsius). Des Moines has approximately 30 days per year with
maximum temperatures at or above 90 degrees and approximately 140 days
-------
11—3
with minimum temperatures at or below 32 degrees. (See Table Il-i.) The
average duration of frost-free periods was between 165 and 186 days at four
different measuring locations in the study area over approximately 20 years.
Relative humidity generally stays between 60 percent of saturation
(p. m. readings) and 80 percent (a. m. readings).
Rainfall
Both frequency and intensity of rainfall in the Des Moines area increase
markedly during the months of March through June. This is followed by a
drop in July, slight increase during August and September and a gradual
decrease until January and February. In 84 years there were eight years in
which annual rainfall exceeded the mean rainfall by more than 10 inches and
three years when the annual rainfall was more than 10 inches below the mean.
(See Table 11-2.)
Winds and Storms
The mean monthly wind speed in the Des Moines area varies from about
nine mph (August) to 14 mpd (March and April). The prevailing direction is
northwest from November through April and south from May through
October. Winds at 15 feet above the ground reach 50 mph (excluding gusts)
about every other year and reach 75 mph once in 50 years.
Approximately 80 percent of 40-50 annual thunderstorms occur during
the warm half of the year. Tornado frequency is highest in May and June and
during afternoon and early evening hours.
Topography
The topography of the study area can be divided into two fairly distinct
regions: (1) the area north of the line of the Wisconsin glacial advance which
-------
11-4
Table Il-i
MEAN, MAXIMUM AND MINIMUM MONTHLY TEMPERATURE*
Month Mean, °F Maximum Minimum
January 20.9 29.7 12.1
February 24.8 33.6 15.9
March 36.4 45.5 27.2
April 50.5 60.6 40.3
May 61.5 71.6 51.3
June 71.0 80.9 61.1
July 76.1 86.6 65.6
August 73.8 84.1 63.5
September 65.5 76.1 54.9
October 54.2 64.8 43.6
November 38.4 47.6 29.1
December 26.2 34.3 18.0
Annual 49.9 59.6 40.2
*Based on 64 years of records.
Source: Iowa DEQ, 1975a.
-------
11—5
Table 11-2
MEAN MONTHLY VALUES OF PRECIPITATION
Month Airport City
January 1.30 1.25
February 1.10 1.11
March 2.09 2.23
April 2.53 2.48
May 4.07 4.03
June 4.71 4.87
July 3.06 3.05
August 3.67 3.88
September 2.88 3.05
October 2.06 2.27
November 1.76 1.72
December 1.14 1.12
Annual 30.37 31.06
Source: Iowa Natural Resources Council, 1953.
-------
11—6
is relatively rolling to undulating; and (2) the area south of the glacial line,
which is rough and hilly. Elevations rise above 1,050 feet in Dallas County
and fall to less than 750 feet along the Des Moines River in the southeast
corner of the study area. The dominant features of the land are the Des
Moines River Valley, a small portion of the Skunk River Valley and the stream
valleys tributary to them. Slopes in the area rarely exceed 10 percent except
along the valley walls.
There are 16 drainage basins in the study area - each divided into from
2 to 20 sub—areas. (See Plate 11-1.) The subareas (103) are the basic units for
data collection and analysis.
Geology
The City of Des Moines is located on the southernmost reach of the
Cary substage of the Wisconsin ice sheet within the study area. East of the
City the southern boundary swings gradually north and crosses the Polk
County border south to Mitchellville. Approximately 12,000 to 13,500 years
have passed since this glacier receded. The surface covered by the glacier is
significantly different from that to the south, where the most recent glacial
advance was the Kansan ice sheet. To the north of the demarcation line, the
land forms are primarily glacial, and the surface is in extreme youth with
respect to erosion and drainage patterns. The divides between adjacent
streams have very little slope. The topography may be called “saucer
topography” because of the shallow, rounded swales which often contain
water and have no outlets. The ground between the swales appears as low,
gently rounded hummocks. In this northern region, the drainage conforms to
the hills — it does not form them. The river valleys are generally quite
narrow, although it is common for the present stream to be cut into the
alluvial bottom of an older, larger valley.
South of the line of the Wisconsin glacial advance, the landscape is in
early maturity with respect to erosion and drainage pattern. The land forms
-------
PLATE Il-I
.. 7
- .N UPPER
7 DES MOINES RIVER ,7 L
UNIS
- M I1E
BE4/ER CREEI I ( 035
099 -
- L I
— ç °
f -! - SIT 09$ /
I . . I
LL A3 0 9 1 \. —, — I -
‘ F ) /
,— c ‘- L — — . o’ i i I C 0 U N 1-
‘9 ’ - . 7 _ “ I
,r ‘ - 1 - ER ( —a
-‘-- . , — L — — — --
L r’ u- ’ CREEK
L E:K Lj..
‘ N 1 ,049
• Q7 I 070 / 0 2 537 U> EEK
7 I
—m- /‘ ,‘ r - ) ‘\I
I — . .r- I - , .
° A__ -’ — . YEADER I ,i L 1
—9-—----- -.. -. _ ) , F_ 1 • •• • 3 052 CRE k L 1 \r o r 1 023
°“
5 0161 . LOWER
: _ _____ ‘7 ’.
I o’. f RIVtR , ‘ ...
ff rR E \ C II b .. ,-•• ...- .9’
BUTCHE
W \ /R I N N 4#SIpDLE CREW ‘
RI 6IERI
‘—r - •
DRAINAGE BASINS
AND SUBAREAS
BASIN BOUNDARY
—— SUBAREA BOUNDARY
031 SUBAREA CODE
IN M IL.E
0 1 2 4
cE g CENTRAL IOWA REGIONAL ASSOCIATION
OF LOCAL GOVERNMENTS
K M KIRKHAM MICHAEL AND ASSOCIATES
HARLAND BARTHOLOMEW AND ASSOCIATES
AMERICAN CONSULTING SERVICES, INC
KIRKHAM TENECH ENVIRONMENTAL CONSULTANT ,
MICHAEL INC • CARLETON D BEH AND COMPANY
PRIPLRAT1ON Of “0 MAP WAS T # >.ED IPROUGIT £ GRANT ‘L ’ 1 9€
S €NVLRONM€N1AL PROTICYLON AC,INCT .11099 SIC lION 2 I 09 191
019*5 WAlER ‘OLLUTION CONTROL ACT AYENDARRNTS 09 “‘2
007
SKUNK
RIVER
‘9
MUD
I
OP
SUTH
RI R
-------
11—8
are clearly those of stream action. River valleys are one to three miles wide,
and there are a large number of tributary streams.
The superficial layer of substrate consists of bess and glacial and river
deposits laid down during the Pleistocene. With very few exceptions, this
superficial material is quite extensive throughout the study area and may
attain depths of several hundred feet. South of the limits of the Wisconsin
ice sheet, a thin veneer of bess covers the uplands. A layer of bess may be
found under the Wisconsin structures in certain places to the north. The
bedrock beneath the Pleistocene mantle consists of shale with interbedded
limestones and sandstone and thin coal seams. The strata are generally quite
horizontal. The bedrock throughout the study area is of the Des Moines series
(Cherokee and Marmaton groups) in the Pennsylvania system. Rocks of lower
geological strata can be found as outcrops sequentially to the northeast of the
study area. A complete stratigraphic column for Iowa is provided for
reference. (See Plate 11-2.)
The greatest depth to bedrock based on data from well logs maintained
by the Iowa State Geological Survey is 280 feet, in the extreme northern part
of the study area near Alleman. This point lies over the pre—glacial “Jordan
channel”, which parallels the present Skunk River channel to the west and
“rejoins” the Skunk River in the northeast corner of the study area. Another
substantial buried, pre-glacial channel is that underlying the present course of
the Beaver Creek. Both of these buried channels serve as substantial water
storage areas and are fed by overlying unconsolidated material.
Significant alluvial aquifers of varying depth and widths line the
following rivers and creeks: Des Moines River, Raccoon River, Skunk River,
Middle River, Walnut Creek, Beaver Creek, and Four-Mile Creek. These
aquifers are continuously recharged by natural storm runoff and are,
therefore, sensitive to significant non-point sources of pollution in the
respective watersheds.
-------
STRATIGRAPHIC COLUMN OF IOWA
SYSTEM SERIES GROUP FORMATION
Quoternary
PIel,toc s.
(.04 ! 0
Cool ’s.. (l .oo bOd 0! ‘ 00 )
00005 0000 -
w o n COot
00•t ! !
S. . .?,& 0 000 00 0 0fl7 tI&
000 0! b 0l
— — —
Crstqceous
DESCRIPTION THICKNESS
aLa 00005)
Jura sSIc
Do0 0 0
Foot 2042. 0000
150
00010! C.p 0005
00
Ill
V Irg Il
Pennsylvanian
Shoot!..
Dooglo.
sa owi
L o s 0 1 ,42
01005.0, C d i
0040400
Des ses
M Or 5 5 0tO R
Meramec
Owge
W0 0 0WtSd
1000000
M 0. OtO
cr 0 000
0 00
42 4 0
L 0 0 4fl.
Foti Scot?
La’—
00000000
SI .0,0.
*0,15°
0 0 0 0Uk
0.000. Cd
500 0 !0 0
SI.,,. Coo.
P , o . o. ot 10 11
(05 1100 R!fl!
MOO? 0011
Ao l ’ , ; to ,
SN.?
0.0. C,..t
SN.?, Roth
CoOoo 1105
WOO * 00 0 I ! 00
Lopoo l. ClIy
0000*000
conUo l ’ . .
CO ..ooo
0000,00. ,.
2.1000
0 0 t l ? ? O
5? 00,0!
00001. 0, 00.0
‘40
fl0
0 0
M IslIsaIppian
Konderhook
00550 04,11
Devon Ion
UDDer
00110o S00?nQ
M ,ddls
Lowe,
Silurlon
NIO gor 1
Aleooosdr .on
Ordoviclan
C lnc lonot oars
Mot sowklcs
clsazyon
Seekman t owo s
Cambrian
St Crotoon
Tt S l ?tp. 0IIO.h
- — —
— — -
Dse.bod l
400
00000
000
00 ! ! lO
00• 0 040S
00
500
005
320
0000000*00 00
0
.4 0 00000 0 0S00l*
Precambrian
• 1
1000501000 — 050.0,! —
‘0
10t05.,l, •0•o0
004000000 5 0 ‘50*5
‘*0
00.0 01000,00! 04*0 ., I nS
PLATE 11-2
-------
11—10
While there was extensive coal mining in the Des Moines area earlier in
this century, the prospects for commercial production returning in this area
do not appear very high at the present. A statewide inventory of coal
resources now in progress may shed more light on this matter (Avcin, 1975).
A potential problem caused by the extensive coal mining activity earlier
in this century is that much of south-central Polk County is underlain by
shallow, mined out voids in the upper bedrock layers which represent possible
subsidence areas. The incidence of subsidence to date is low, however, and
the change of major subsidence appears to be very low.
An underground (bedrock) storage area for liquid petroleum gas (LPG) is
located east of Pleasant Hill with substantial storage volumes at depths of
375 and 575 feet (Dorheim, 1975).
Data on the distribution of recent earthquakes and the map of seismic
risk zones in the United States indicate that the probability of significant
earthquakes or tremors in the study area is relatively small (Spencer, 1972;
Cargo and Mallory, 1974). There are no known fault zones in the area along
which tremors are likely to develop.
Soils
Soils in the study area, as a whole, are highly productive agricultural
soils of Class I or II capability. Most of the land is slightly sloping with
steeper slopes limited to the sideslopes of the larger river valleys. The
following paragraphs describe the salient characteristics and general location
of the major soil associations in the study area. Appendix A-i provides more
detailed information.
1. Clarion-Nicollet-Webster .
Much of the northern two-thirds of the study area is covered with these
soils. They are highly productive for agricultural purposes and range in
-------
11—11
drainage characteristics from well to• poorly drained. The soils in this
association, especially Clarion, produce some runoff from gently sloped areas.
This association is the most intensively cropped in the area, with corn and
soybeans being the major crops. Because of the large extent of seasonally
bare soil, there is often the potential for considerable erosion. This potential
is minimized by the absence of steep or long slopes. Generally, both erosion
and deposition are quite local, from the morainal knolls to adjacent swales
and potholes. Only fine clays and organic matter are apt to remain suspended
in runoff long enough to be carried off the landscape and into streams and
rivers.
2. Hayden-Lester .
These soils are found on the steeper slopes along major streams and
occur along the Des Moines River north of the Rac oon confluence and along
the Skunk River. They are well drained, moderately productive and generate
considerable runoff.
Soils in this association have the greatest erosion potential per unit area
if mismanaged, due to their location on steep slopes and their erosive nature.
Use of lanc having this soil association for woodlands and pasture minimizes
the erosion problems and small grains and hay are far better than row crops if
it used for cropping.
3. Colo—Waukegan-Dickinson-Dorchester .
These soils are found on bottomlands or on benches along the Des
Moines, Raccoon, and Skunk Rivers. Formed primarily from outwash and
alluvium, they are well drained, except for Cob, which is poorly drained.
They have moderate agricultural productivity but are subject to flooding or
standing water for parts of the year. These soils are not generally subject to
erosion, but localized deposition and/or scouring may take place in times of
flooding.
-------
11—12
4. Fayette-Downs .
These bess soils occur on gentle slopes north of the Des Moines River in
the southeast corner of Polk County. They are well drained, have high
agricultural productivity and produce substantial runoff. They have consider-
able erosion potential if mismanaged because of their light, fine texture.
4A. Ladoga-Lindley .
Ladoga-LindleY soils are found south of the Des Moines-Raccoon
confluence. These soils are formed in medium fine-textured bess and till on
gently sloping to steep landscapes. Erosion is a hazard due to the frequency
of steeper slopes. A fine, well integrated drainage network conveys
sediments rapidly to streams. Woodland and pasture cover in this area would
effectively mitigate the erosion hazard.
5. Tama-Muscatine .
These soils are formed in deep, medium-textured bess on nearly level
and gently sloping landscapes. The area is intensively cultivated to row
crops, which exacerbates its erosion potential, especially where slopes are in
excess of five percent. Large fields with long gentle slopes may be subject to
severe sheet and nil erosion during intense rains. Sediments are conveyed
rapidly to drainageways and streams and removed from their points of origin.
5A. Sharpsburg-Shelby .
These soils are formed in medium fine-textured bess, moderately deep
to shallow over paleosols (old soils) and in unweathered Kansas-aged glacial
till. Erosion is only a moderate hazard except where they are exposed in row
crop cultivation. Erosion hazard on paleosol exposures will be severe unless
good plant cover can be maintained. The unweathered Kansas-aged till soils
-------
11—13
will have a moderate erosion hazard, particularly since they have a greater
frequency of steeper slopes. Permanent cover should be maintained on
paleosol and till-derived soils in this area.
6. Sparta-Farrar-Chelsea .
These are very sandy soils found along the Upper Des Moines and Skunk
Rivers. They are excessively drained, not highly productive, - moderately
sloped and produce considerable runoff. They are not particularly subject to
water erosion except where there is concentrated runoff from above. In fact,
deposition may even occur in areas near footsiopes and where streams spread
out on the terrace or on bottomlands. In large parts of this area where there
are coarse-textured soils, wind erosion can be a particularly severe hazard.
These soils are not used extensively for row crops.
Hydrology
Rainfall
The average rainfall in the study area is approximately 31 inches per
year. An estimated 68 to 70 percent (or 21 to 24 inches) of this either
evaporates from moist surfaces or is transpired by plants. This leaves seven
to 10 inches, with up to six inches becoming surface runoff and approximately
three inches entering the soil as infiltration (Twenter and Coble, 1965, p. 21).
Major Streams
The major streams in the study area flow southeastwardly through
broad, pre-glacial valleys. The Des Moines River is the dominant one and lies
at depths approximately 150 to 200 feet below the upland plain through the
study area. It drains approximately 13,000 square miles in the State of Iowa
and approximately 14,500 square miles totally (Iowa Natural Resources
Council, 1953, p. 3).
-------
11—14
The largest tributary of the Des Moines River is the Raccoon, an
exception to the general southeasterly direction of flow or major rivers in
that it enters the Des Moines River at a direction of slightly south of west.
The other major tributaries of the Des Moines River in the study area are
Beaver Creek, Four Mile Creek and Middle River. Walnut Creek is the
principal tributary of the Raccoon River in the study area.
Reservoirs
Two man-made structures in the Des Moines area will strongly influence
the hydrology of the Des Moines River and its tributaries: Saylorville Lake
(dam is 213.7 miles upstream from the mouth), scheduled for completion in
April, 1977, and Lake Red Rock (dam is 142.9 miles upstream from the
mouth), which became operational in 1969. Saylorville Lake has a
conservation pool elevation of 833 feet, with a surface area at that elevation
of approximately 5,400 acres extending 13 miles (17 river miles) upstream.
At the flood control pooi elevation of 890 feet, the Lake has a surface area of
about 16,700 acres extending approximately 45 miles (54 river miles)
upstream. The dam is designed to control flows from a drainage area of
approximately 5,823 square miles and when operated in conjunction with the
completed local flood control works will provide flood protection up to the
level of the 165—year recurrence frequency. Saylorville Lake will reduce the
range in low rates from 20 to 60,000 cfs to 200 to 21,000 cfs (U.S. Army
Engineering Division, 1974, p. 111-7).
Lake Red Rock is outside the 208 study area, but its hydrology and
water quality are strongly affected by activities in the study area. The Lake
covers approximately 9,000 acres at conservation pool elevation of 725 feet
and 65,500 acres at flood control pooi elevation of 780 feet. The flood pool
extends well into the southeastern corner of the study area.
-------
11—15
The Des Moines and Raccoon River basins each have small lakes in them
which originated either naturally as isolated meanders of the parent stream
or as man-made lakes or both. They include Grayts Lake, Horseshoe Lake,
Fisher Lake, Avon Lake, Randleman Lake and many unnamed gravel pits.
Big Creek Lake, created in 1972 by a diversion dam on Big Creek, was
made to protect the Polk City area from flooding by Saylorville Lake. It has
a surface area of 885 acres at normal pooi elevation of 920 feet, and the
flood pooi is not expected to increase its elevation more than five feet.
Water Quality and Quantity
A discussion of water quality and quantity in the Des Moines 208 study
area can be divided into three major areas, the Des Moines River, the
Raccoon River, and other streams in the study area.
Water quality data from the Des Moines River Basin in Iowa has been
compiled by the Iowa Department of Environmental Quality (IDEQ). There
are seven sampling stations in the vicinity of the 208 study area. (See Table
11-3.) Four stations are upstream of Des Moines, one station on the southern
edge of Des Moines, and two stations located downstream of Des Moines. The
two downstream stations are located on either end of Red Rock Reservoir.
The most intense sampling occurred between 1968 to 1974 when
sampling was performed approximately weekly. Parameters covered by the
stations submitting data include: dissolved oxygen, biochemical oxygen
demand (BOD), organic nitrogen, nitrate, total nitrogen, orthophosphate, pH,
temperature, turbidity, total hardness, total alkalinity and total carbon.
Although there is insufficient data from these seven stations to allow a
detailed analysis of the water quality of the Des Moines River in the area of
Des Moines, there is ample data to indicate possible trends in the quality of
water as it flows through the study area. Because the data from these
-------
11—16
Table 11-3
LOCATION OF IDEQ REPORTED SAMPLING STATIONS
Des Moines, Iowa 208 Area
Sampling Station No. Loèation
1 Boone Water Plant
Des Moines River
2 Highway 89 Bridge 2 Miles
West of Madrid
3 County Road Bridge 4 Miles
West 2.5 Miles North of
Polk City
4 Polk County Road 2 Miles
South of Polk City
5 Highway 46 Bridge in
Des Moines
6 Highway 14 Bridge at Red
Rock Lake
7 1 Mile Downstream from
Red Rock
-------
11-17
stations along the Des Moines Riyer is reported for only a few years and in no
one year did all seven station subrrdt data, averaged values from the data of
each station provide the water quality indication that is most useful.
Tables 11-4 and 11-5 present the mean summer and winter water quality
values for the Des Moines River for 1968 through 1974. A brief discussion of
several water quality parameters which greatly influence water quality in the
Des Moines area follows:
Dissolved Oxygen - Examination of the dissolved oxygen data indicates
that the Des Moines River con airs an acceptable 4mount of dissolved
oxygen. The pxygen saturation level for water at 20°C is 9.2 mg/l; at 5°c
the saturation level is 12.8 mg/I. As the temperature of water rises, its
ability to absorb or retain oxygen decreases.
From the summer water quality data, a rather large decline in the
dissolved oxygen concentration occurs as the Des Moines River flows
through the City of Des Moines. This decrease in the dissolved oxygen
concentration may be partially related to a corresponding rise in water
temperature whicti may be related to the use of river water or cooling
purposes. (See Table 11-4.)
Biochemical Oxygen Demand - The BOD levels of the Des Moines River
are relatively low, 3 to 11 mg/i. The summ r and winter data indicate
the effects of Red Rock Reservoir on the BOD levels of the river. The
reservoir allows for the settling of organic matter and results in lower
BOD levels in water discharged from the reservoir.
- The pH of the Des Moines River is within the 6.5 to 9.0 standard
range limit and fluctuates only s1ig itly as it flows through this segment.
Ortho-phosphate - Ortho—phosphate levels in the river through the
winter months are relatively stable except for a peak which occurred at
-------
11-18
Table 11-4
SUMMER WATER QUALITY OF THE DES MOINES RIVER
1968-1974
Des Moines, Iowa 208 Area
Ortho
Station D.O.(mg/1) BOD(mg/1) P0 4 (mg/I) Temp. °C
1 10.21 8.66 .24 8.25 20.95
2 10.01 11.30 .20 8.23 21.35
3 9.80 10.51 .52 8.36 21.21
4 9.57 10.99 .18 8.29 21.04
5 8.45 7.27 .55 8.07 22.95
6 8.30 3.38 .36 8.06 21.32
7 9.47 3.44 .35 7.97 21.61
-------
11—19
Table 11-5
WINTER WATER QUALITY OF THE DES MOINES RIVER
1968 -1 974
Des Moines, Iowa 208 Area
Ortho
Station D.O. (mg/i) BOD( mg/i) P0 4 ( mg/i) Temp. °C
1 13.22 6.77 .64 8.12 3.78
2 14.94 8.68 .64 8.12 3.47
3 i3.60 9.14 .62 8.19 3.61
4 13.40 9.61 .54 8.03 3.71
5 12.43 6.01 .86 8.17 5.13
6 11.48 3.41 .46 7.97 4.75
7 13.87 4.17 .64 7.87 4.90
-------
11—20
Station No. 5. This increase also occurred at Station No. 5 during the
summer at the point where the river flows through the City of Des
Moines past its confluence with the Raccoon River.
Temperature - Temperature levels of the Des Moines River are
relatively stable and well below the 32°C stream standard limit. A
temperature peak is reached at Station No. 5 in both the summer and
winter.
Results of various studies have reported the water quality conditions in
the Des Moines River. A study of the Des Moines River from Fort Dodge to
Des Moines was completed during the summer of 1973 (Iowa State Hygienic
Laboratory, 1974). Water quality was quite good during this study period as a
result of high flow conditions. Dissolved oxygen levels ranged from 7.2 to 8.6
mg/i in June, 1973, and from 7.6 to 19.8 mg/l in August of that same year.
BOD readings varied from 1 to 5 mg/i and from 5 to 16 mg/i during the same
two-month time period. In addition, fecal coliform concentrations averaged
1,000/lOOm!. No ammonia nitrogen data were presented in this report.
Saylorville pre-impoundment studies from 1964 to 1970 (Bauman and
Kelman, 1970, Baumari and DeBoer, 1972) on the Des Moines River have been
carried out regularly by personnel at Iowa State University. BOD levels in
the late summer of 1970 averaged 18 mg/i with orthophosphate generally
present at a concentration below 0.5 mg/i. Ammonia nitrogen remained less
than I mg/i except for January-February 1970 when the river was at the
freezing point. Organic nitrogen varied from 0 to 3.02 mg/i during this study.
Dissolved oxygen measurements showed variations from 15.9 mg/l in
February, 1970 to a low of 5.8 mg/i in July, 1970.
The following year ammonia nitrogen levels varied from 0 to 2.88 mg/i
as N. These ammonia nitrogen concentrations remained below 0.9 mg/i as N
-------
11—2 1
except for just below Des Moines where concentrations were generally higher.
Orthophosphate levels ranged from 0 to 3.9 mg/i but were usually below 1.0
mg/i. BOD levels indicated high values of around 30 mg/i in March, 1972
during the period of spring flooding. Fecal coliforms were found to be
generally higher below the City of Des Moines.
A follow-up Saylorville area study (Bauman and Oulman, 1973) in 1973
detailed water quality conditions in the Des Moines River from Boone to Red
Rock. A number of parameters were discussed in this pre-impoundment
study. BOD levels varied from 0.2 mg/i below Red Rock to 18 mg/l at
Saylorville in September, 1973 . However, the normal BOD range of the Des
Moines River was observed to be 2 to 7 mg/l. Dissolved oxygen
concentrations were noted to be at a minimum (3.55 mg/i) in September, 1972
at Red Rock Reservoir. Maximum dissolved oxygen levels (23 mg/i) were
observed at Boone in September, 1972. The minimum dissolved oxygen value
coincided with the maximum turbidity reading, with maximum values
occurring during periods of high algal activity.
Ammonia nitrogen concentrations on the Raccoon River varied from a
low of 0.03 mg/l in October, 1972 to 1.0 mg/I in March, 1973. Ammonia
nitrogen levels below the confluence of the Des Moines and Raccoon Rivers
averaged somewhat higher than those at upstream stations on both rivers.
Orthophosphate levels were lower in 1972-73 compared to 1971-72. The
maximum orthophosphate concentration was 13 mg/i as P0 4 3 near the con-
fluence of the Des Moines and Raccoon Rivers with a normal range of 0.2 to
0.6 mg/I.
Fecal coliform measurements made during this study were highest in
the Raccoon River and directly downstream from the Des Moines wastewater
treatment plant. Red Rock stations frequently detected no fecal coliform
organisms. Fecal coliform averages in these three areas were 3,386/lOOml,
4,346/lOOmi, and 153/1 00 ml.
-------
11—22
The Raccoon River is the other major stream in the 208 planning area.
The North Raccoon River has been the subject of many investigations in the
past - particularly with reference to concentrations of dissolved oxygen and
ammonia during the winter months below Storm Lake, Jefferson, Perry and
Adel (Iowa Department of Environmental Quality, 1975b). No water quality
violations have been observed on the Middle and South Raccoon Rivers during
high flows. Low-flow periods have not, however, been sampled in the Middle
and South Rivers. A pollution potential appears to exist for the entire reach
of the river when flows approach the 10-year 7-day low flow value. Data in
these studies have not revealed violations of the Iowa Water Quality
Standards from Van Meter to Des Moines although a potential for pollution
may exist (Iowa Department of Environmental Quality, 1975b).
Little data is available for the main stem of the Raccoon River through
the study area. Some information is available in the Baumann studies
(Baumann and Oulman, 1973) and has been discussed previously. Generally,
water quality in this portion of the Raccoon River is very good because no
point-source discharges are located there.
Various streams tributary to the Des Moines River flow through the 208
study area, including Beaver Creek, Walnut Creek, North River, South River,
Middle River, Yeader Creek, Mud Creek, and Camp Creek. A small amount
of water quality data is available regarding these streams (Iowa Department
of Environmental Quality, 1975c). Turbidity has been noted as a problem in
all of these rivers with a mean turbidity level of approximately 75 JTU
(Jackson Turbidity Unit). Dissolved oxygen concentrations in these streams
are usually well above Iowa stream standards, yet fecal coliform levels have
been found to exceed the EPA guideline of 200/100 ml. Water quality data
indicate poorer water quality in the Middle River than in the North or South
Rivers, with best water quality in the North River.
Data describing the water quality of other tributary streams in the
study area is minimal and no regular sampling programs have been initiated
on these streams.
-------
11—23
With regard to groundwater quality, alluvial deposits which underlie the
Des Moines River are important sources of water. These deposits have a
large storage capacity with frequent recharge from precipitation and
groundwater aquifers. The bedrock aquifers in the area yield large quantities
of water and are separated by relatively impermeable aquicludes. The water
quality varies significantly from aquifer to aquifer. The important aquifers in
the Des Moines River basin are the alluvial aquifers, Dakota sandstone, the
St. Lawrence aquifer (up to 1000 gpm), lower Pennsylvania sandstone, the
Jordan Aquifer (up to 1000 gpm), and Dresbach sandstone (less than 100 gpm).
The Dakota sandstone yields moderate to large quantities (50-500 gpm) of
somewhat mineralized water in the upper part of the basin. Pennsylvania
sandstone is widespread but yields only small quantities of highly mineralized
water. Mississippian limestones in Polk and Dallas Counties yield a few
gallons per minute of water which is at least moderately mineralized and
possibly high in fluoride (Iowa Department of Environmental Quality, 1975d).
Nearly all of Iowa ’s grouridwaters are very hard (250-500 mg/l calcium
carbonate equivalents). Alluvial aquifers offer good-to-fair quality water
with underlying bedrock aquifers containing mineralized water. Water quality
varies depending on the thickness of the aquifer, the depths of the wells, the
underlying aquifer on aquiclude, and whether the water is coming from
storage, induced infiltration, or from rainfall. Alluvial deposits usually
contain water with less than 500 mg/i total dissolved solids. These
groundwaters are of the calcium bicarbonate or calcium magnesium bicarbon-
ate type.
A notable exception is the lower reach of the Raccoon River. Maps
indicate that water from alluvial deposits under the river contains between
500 to 1,000 mg/i total dissolved solids (Iowa Department of Environmental
Quality, 1975b).
Concentrations of 2,500 mg/l total dissolved solids with excessive
fluoride from the Mississippian limestone and the Silurian-Devoniari aquifer
-------
11—24
are common in the Des Moines 208 planning area. Analyses from the Jordan
aquifer show high fluoride concentrations west and southwest of Des Moines
of 2.0 to 3.0 mg/i and total dissolved solids of 500 to 1,000 mg/i. In general,
this water supply contains less minerals than other sources of groundwater
from bedrock aquifers.
The City of Des Moines obtains its water from the sand and gravel
alluvial aquifers of the Raccoon River: Maff it reservoir serves as a back-up
supply which can be discharged to the Lower Raccoon River as needed.
Groundwater from unconsolidated aquifers in the area is generally hard (200
mg/i as calcium carbonate) and the total dissolved solids level has on occasion
exceeded 500 mg/i. Iron concentrations (0.3 mg/i) have been of concern in
some localities in the area (Upper Mississippi River Comprehensive Basin
Study Coordinating Committee, 1970).
The City of West Des Moines draws water from the Jordan aquifer and
uses shallow wells for emergency supply. Certain underground gas storage
facilities pump water from the St. Lawrence aquifer.
A partial analysis of water from bedrock formations in the state is
illustrated in Table 11-6 for comparison purposes. Other applicable data is
shown in Table 11-7.
Detailed reports of existing groundwater quality in the state do not
exist to any great extent.
With regard to groundwater quality, there are various aquifers in
central Iowa. The shallow aquifers in the Des Moines study area consist of
irregular layers of unconsolidated rocks, silt, clay, sand and gravel. They may
be subdivided into alluvial aquifers, buried channel aquifers and drift aquifers.
Shallow aquifers are the water source for nearly 100 cities and communities
-------
11—25
Table 11-6
REPRESENTATIVE PARTIAL ANALYSES OF WATER FROM BEDROCK FORMATIONS
(All values in milligrams per liter)
Des Moines, Iowa 208 Area
Iron Bicarbonate Sulfate Chloride Dissolved Hardness
______ (re) ( HCO ) ( SO ) (C l) Solids ( as CaCO
Cretaceous Aquifer
Estherville (Emmet Co.), Iowa 1 8 442 5.0 1,175
Pocahontas (Poehontas Co.), Iowa .36 525 15 1,300
Mississippian Aquifer
728 552
531 380
Silurian-Devonian Aquifer
6/14/60 .06 264
8/16/52 .96 283
7/13/61 3 2 410
9/4/51 .2 378
Location
Date of
Sampling
11/5/56
3/7/6 2
10/ 4/5 1
8/3/60
504
553
9 481 218
02 398 75.7
766
820
Ft. Dodge (Webster Co.), Iowa
Sigourney (Keokuk Co.), Iowa
Cedar Falls (Black Hawk Co.), Iowa
Edgewood (Clayton Co.), Iowa
Northwood (Worth Co.), Iowa
Near Volga (Clayton Co. ), Iowa
Belleville (Dane Co.), Wise.
Charles City (Floyd Co. ), Iowa
Fairfield (Jefferson Co. ), Iowa
Ft. Dodge (Webster Co.), Iowa
Galesburg (Knox Co.), Ill.
Iowa City (Johnson Co.), Iowa
Jefferson (Greene Co.), Iowa
Madison (Dane Co.), Wise.
Oregon (Ogle Co. ), Ill.
5.0
19
2
2.0
3
7.0
308 252
288 270
377 337
376 333
12/29/44
6/1 4/60
8/1 4/60
1 0/5/51
1/9/46
11/27/62
12/8/60
2/2/6 1
7/16/4 8
42.4
10
13.0
31
6.4
41.2
455
192
559
554
418
73
15 2
Cambrian-Ordovician Aquifer
0 381
22 283
20 298
1.2 436
.5 0
.52 283
593 312
1 405
.3 0
3.8 292
7 326
129 1,146
89 779
215 1,399
54 1,167
97 1,048
16 476
6.0 286
330
256
340
479
279
470
234
434
292
Source Upper Mississippi River Comprehensive Basin Study, 1970
-------
11—26
Table 11-7
REPRESENTATIVE PARTIAL ANALYSES OF WATER FROM UNCONSOLIDATED AQUIFERS
(All values in milligrams per liter)
Des Moines, Iowa 208 Area
Date Of Iron Bicarbonate Sulfate Chloride Dissolved Hardness
Location Sampling (Fe) ( IICO ) ( SO ) (Cl) Solids ( as CaCO
Near Barnum (Webster Co.), Iowa 12/28/46 4 1 410 247 6.5 756 488
Boone (Boone Co.), Iowa 6/15/60 .24 373 96.1 18 550 412
Cedar Rapids (Linn Co.), Iowa 10/24/61 9.9 351 105 28 494 412
Dubuque (Dubuque Co. ), Iowa 2/26/60 .52 334 17.5 9 326 313
Eddyville (Wapello Co.), Iowa 11/02/61 16 215 92 0 1 352 266
Erie (Whiteside Co. ), III. 11/1 6/60 Tr 0 28.0 2 246 178
Lee (Lee Co.), Ill. 10/04/47 4 0 2.5 2 0 240 149
Marengo (Iowa Co.), Iowa 11/05/59 .71 222 54.3 6 321 236
Near Oregon (Dane Co.), WiSe. 4/18/60 .05 290 18 5.5 0 266
Rockford (Winnebago Co.), III 6/10/48 2 7 0 56.0 9 . I) 102 400
Sigourney (Keokuk Co.), Iowa 8/30/60 2.06 234 86.4 18 380 220
Near Stoughton (Dane Co.), Wise. 4/19/60 .2 344 31 14 0 332
Vinton (Benton Co.), Iowa 12/27/60 2.46 288 15 6 1 273 244
Waterloo (Black Hawk Co.), Iowa 6/22/60 .06 239 26.5 5 280 240
West Des Moines (Polk Co ), Iowa 9/03/63 4.0 321 94 0 6.5 457 344
Source Upper Mississippi River Comprehensive Basin Study, 1970
-------
11—2 7
in central Iowa. The Des Moines Water Works water supply is obtained from
shallow alluvial aquifers along the Raccoon River through infiltration
galleries recharged directly from the river. They also supply individual users
in locations not having municipal systems. Shallow aquifers generally yield
moderate to large quantities of water. However, there is considerable
variation in both the yield and the quality of water drawn from these
aquifers.
Aquifer recharge areas for surficial aquifers are generally found
directly over or very near the aquifers themselves. Recharge of bedrock
aquifers often will take place by way of alluvial channels passing over the
bedrock aquifers or parts of them. Regions of rock outcropping may also
indicate a recharge area by direct connection with surface water sources.
Cities and towns in the study area which have bedrock wells include
Altoona, Ankeny, Grimes, Granger, Waukee and West Des Moines. Bondurant,
Norwalk and Waukee use water from upper bedrock aquifers and are
therefore, somewhat more susceptible to polluted recharge.
Water Quality and Quantity Problems
Identification of existing water quality and quantity problems has been
partially discussed in previous sections. Various studies have indicated
additional problems reported in the form of water quality violations.
Water quality violations have been observed from Des Moines to Red
Rock Reservoir. Data obtained in 1968 when renovation of the main Des
Moines treatment plant was taking place indicated dissolved oxygen, ammonia
nitrogen, and fecal coliform violations.
The significance of this information should be considered in light of the
Saylorville darn. Projected flows at Des Moines will be at a minimum of 200
-------
11—28
cfs as opposed to the 10-year 7-day low flow of 82 cfs. Surveys in 1968, 1973,
and 1974 have reported on water quality in this segment of the river. Few
violations have taken place, and those that have occurred primarily in 1968.
High concentrations of ammonia nitrogen were found in conjunction with low
levels of çlissolved oxygen.
Fecal coliform violations have also been noted In 1973 and 1974, as well
as in previous years, below the Cit i of Des Moines, Disinfection at the Des
Moines Wastewater Treatment Plant has been instituted and should help to
alleviate fecal coliform violations. However, some background level of fecal
coliforms will always occur b 1ow Des Moines from non-point sources and
bypasses.
A water quality survey of the Des Moines River at Des Moines in 1970
(Iowa State Hygienic Laboratory, 1970) focused on three major stations
within the city limits, as well as the Highway 14 bridge station. 39 miles
downstream from the Des Moines Wastewater Treatment Plant. Relatively
elevated flow conditions of the Des Moines River were sampled during this
study wish minimum sampled flows of 250 cfs during February 1968, 550 cfs
in February 1970, and 250 cfs in September 1970. The sampling dates were
chosen to represent different seasons of the year.
Organic and nitrate-nitrogen concentrations were observed to be
increased slightly by the Des Moines Wastewater Treatment Plant effluent,
especially during periods of low flow. The concentrations of these
parameters also varied si bstantially in the Des Moines and Raccoon Rivers
upstream from the Des Moines Wastewater Treatment Plant discharge and
were dependent upon river flow, algal blooms, etc.
Ammonia-nitrogen concentrations were definitely increased by the Des
Moines Wastewater Treatment Plant effluent. Although the limit of 2.0 mg/i
specified by the Iowa Water Quality Standards was not exceeded in the Des
Moines River, concentrations as high as 1.9 mg/i were observed in January
-------
11—29
and 1.5 mg/i in September . As would be expected, there was a substantial
seasonal variation in ammonia-nitrogen levels with concentrations approach-
ing 1 mg/l in winter and spring above Des Moines. However, during the
warmer months ammonia-nitrogen concentrations were generally below 0.1
mg/I. During the winter months the increased ammonia-nitrogen concentra-
tions persisted to the headwaters of the Red Rock Reservoir.
Soluble and total phosphate concentrations in the Des Moines River
were substantially increased by the discharge of the Des Moines treatment
plant and these elevated concentrations persisted to the headwaters of the
Red Rock Reservoir. The decreases in phosphate levels which occurred
between the Iowa Power and Light Company (IPALCO) and Highway 14
station indicated some assimilation by the periphyton or attached growth as
well as the possible dilution effect which may occur in this stretch of the
river because of IPALCO’s discharge.
In addition to the information presented above (Iowa State Hygienic
Laboratory, 1970), physico-chemical data were collected and reported on
September 3rd and 8th, 1970 while the Des Moines and Raccoon River flows
were 290 and 270 cfs, respectively, which are relatively low-flow conditions.
The September 3 data indicated that water quality in the Des Moines
and Raccoon Rivers above the wastewater treatment plant was acceptable.
Bacterial levels were low, dissolved oxygen concentrations were above the
required 5 mg/I level, and ammonia-nitrogen and phosphate levels were low.
The results from the analysis of the water sample collected at the railroad
bridge about one mile downstream from the wastewater treatment plant were
indicative of a waste discharge upstream. This was evidenced by increased
fecal coliforms, ammonia-nitrogen and phosphate concentrations. The
analysis of the IPALCO sample demonstrated the effects of the Des Moines
wastewater treatment plant on the Des Moines River. While the water
-------
11—30
quality standard for ammonia-nitrogen was not violated in the Des Moines
River, concentrations as high as 1.6 mg/i were observed. Fecal coliform
concentrations had increased from 2,300 to 16,000 and total phosphate
concentrations had increased sevenfold.
The September 8, 1970 data substantiate the data in the September 3
study and demonstrate how far downstream these water quality changes
persist. Ammonia-nitrogen concentrations decrease downstream but at the
Highway 14 bridge sampling stations concentrations are still considerably
higher than normal summer levels. Phosphate concentrations also slowly
diminish downstream but are still substantially higher than normal at the
Highway 14 station which is 39.3 miles below the Des Moines Wastewater
Treatment Plant outfall. Fecal coliform numbers were reduced to normal
ranges within 20 river miles of the wastewater treatment plant.
Dissolved oxygen data secured during this water quality survey were
based on sampling performed during the early morning hours (5:00 to 8:00 AM)
of September 3, 5, and 8, 1970. This time of day was chosen because
dissolved oxygen levels are expected to be minimal at this time due to
elevated respiration of algae and other microorganisms. On all three
occasions dissolved oxygen levels above the Des Moines Wastewater Treat-
ment Plant were above the Iowa minimum standard. However, on September
3 there was only one dissolved oxygen reading above 4.0 mg/i over a 16 mile
stretch below the plant outfall with a low of 2.6 mg/l recorded 10 miles
downstream from the discharge. On September 5 all of the dissolved oxygen
readings for a 16 mile stretch below the wastewater treatment plant were
below the 4.0 mg/i minimum standard with recovery occurring approximately
21 miles downstream from the discharge. On this date the low dissolved
oxygen reading was again 2.6 mg/i occurring about 9 miles downstream from
the Des Moines discharge. The profile of the dissolved oxygen concentrations
in the Des Moines River on September 8 is generally higher than those of
September 3 and 5; however, the 4.0 mg/i dissolved oxygen absolute minimum
standard was still violated nine miles downstream of the Des Moines
treatment facility discharge.
-------
11—3 1
Decreases in dissolved oxygen concentr tions were observed in the
summer of 1973 at Runnells and the Highway 14 bridge below Des Moines
with little change noted at other times of the year (Iowa (State) Department
of Health, 1934). BOD levels during this period were approximately 5 mg/i.
These data clearly indicate that the discharge of the existing Des Moines
wastewater treatment facility combined with intermittent and other point
sources can reduce the dissolved oxygen level of the river below acceptable
levels, particularly under low-flow conditions.
Problem Areas
Reported problem areas indicate that the Des Moines Wastewater
Treatment Plant is a major point-source discharger in the study area. There
are numerous other municipal and industrial dischargers in the area which
tend to add to the overall pollutional problems, but not nearly to the extent
that the main Des Moines plant presently does. One major discharger which
may cause potential water quality and quantity problems is the Iowa Power
and Light Company, as previously described, which withdraws a large quantity
of water from the Des Moines River and discharges cooling water.
Water Uses
Water consumption in the 208 area is expected to increase from
33,500,000 to 57,000,000 gallons per day by the year 2000. (See Table 11—8.)
The projected figures are based on the assumption that the daily average for
each land use category stays constant between 1975 and 2000. A one percent
per year increase in water consumption in all land use categories would result
in a total projected consumption in 2000 of approximately 71,000,000 gallons
per day instead of 57,000,000 gallons per day.
The City of Des Moines draws its potable water from alluvial aquifers
along the lower Raccoon River. Dale Maffit Reservoir, located at the
-------
11—3 2
Table 11-8
AVERAGE DAILY WATER CONSUMPTION
1975
Intensity
Development Cat.*
Acres
Ann. Daily Avg.
( gal. / ac. / day )
Consumption
( gal. / day )
(33,558,000 gals./day 315,000 persons = 105 gals./person/day)
PROJECTED DAILY WATER CONSUMPTION
2000
Intensity
Development Cat.*
Acres
Ann. Daily Avg.
( gal.Iac. / day )
Consti m ption
( gal. / day )
1.
R-LD
6,763
245
1,656,900
2.
R—MLD
7,970
320
2,550,400
3.
R—MHD
13,820
750
10,365,000
4.
R-HD
2,253
1,385
3,120,400
5.
NR—LIU
5,525
985
5,442,100
6.
NR—LIUS
780
1,410
1,099,800
7.
NR—MIU
4,359
795
3,465,400
8.
NR—HI
210
27,895
5,858,000
Total
41,680
33,558,000
1.
R—LD
10,885
245
2,666,800
2.
R-MLD
3.
(12,252)
R-MHD
3 755
‘
320
3,920,600
(24,503)
750
18,377,300
4.
R-H [ )
4,995
1,385
6,918,100
5.
NR—LIU
10,512
985
10,354,300
6.
NR—LIUS
2,311
1,410
3,258,500
7.
NR—MIU
8,946
795
7,112,100
8.
NR—HE
149
27,895
4,156,400
Total
74,553
56,764,100
(56,764,100 gals./thy 400,000 p r ons = 140 gals./person/day)
-------
11—33
Table 11-8 (Continued)
*R..LD: Residential, low density (less than one dwelling per acre).
R-MLD: Residential, medium low density (1 to 2.9 dwellings per acre).
R-MHD: Residential, medium high density (3-6.9 dwellings per acre).
R-HD: Residential, high density (seven or more dwellings per acre).
N R-LIU: Non-residential, low intensity/urban (retail shops, warehouses).
NR-LIUS: Non-residential, low intensity, special (hotels, motels, offices,
laundries, etc.).
NR-MIU: Non-residential, medium intensity (manufacturing, hospitals,
schools, bottling and cannery plants).
NR-H1: Non-residential, high intensity (downtown offices, hotels, etc.).
-------
11—34
meeting point of Polk, Warren, Dallas and Madison Counties, was created as a
backup supply. The water level in the reservoir is maintained by pumping
from the Raccoon River during good flow conditions. Under low flow, water
would be released from the reservoir to enhance stream flow on the lower
Raccoon. (The Reservoir receives very little runoff.)
Surf icial aquifers are also used as water sources by Elkhart, Polk City,
Grimes, Johnston and Mitcheilville (Twenter and Coble, 1965, p. 42). Cities
and towns in the study area which have bedrock wells include Altoona,
Ankeny, Bondurant, Grimes, Norwalk, Runnells, Waukee and West Des Moines
(well logs maintained by Iowa Geological Survey, Iowa City).
Withdrawal of water from the lower Raccoon alluvial aquifers by the
City of Des Moines Walerworks is roughly equal to all other withdrawals in
the study area (40 to 50 cfs). While the supply of groundwater throughout the
study area appears to be quite adequate in relation to projected use,
protecting the water quality in the Raccoon River and its tributaries should
continue to receive very high priority.
Water Quality Management
Federal agencies involved in planning for water quality include the
Corps of Engineers and the U.S. Soil Conservation Service. The Corps, in
cooperation with other Federal, State and local agencies engages in
comprehensive, basin-wide studies such as assessment of floor control needs,
major drainage, irrigation and supply and quality control of potable water
sources.
The Soil Conservation Service gives technical assistance to land owners
in matters related to soil and water conservation. This service is provided
through Iowa Department of Soil Conservation and soil conservation districts
organized under State laws.
-------
II- 35
State agencies (other than Iowa Department of Soil Conservation)
involved in water quality planning include the Department of Environmental
Quality (DEQ), the Natural Resources Council and the Office of Planning and
Programming. The DEQ has the power and responsibility to develop
comprehensive plans and programs for the prevention, control and abatement
of new, increasing, potential or existing water pollution. The DEQ develops
complete river basin plans for the purpose of guiding all water quality
management efforts in the respective basin. This basin planning process is a
continual one - updated constantly for changes in population, industrial
activity and state of the art in water quality management techniques.
The Natural Resources Council is responsible for the comprehensive
state-wide plan to control, utilize and protect water resources of the State.
A member of the Natural Resources Council officially represents the State of
Iowa on all water resource planning efforts affecting Iowa water resources.
The Council grants all permits for withdrawal of water for public consump-
tion or industrial use.
The Office of Planning and Programming coordinates the development
of physical, economic and human resource programs to promote the efficient
and economic utilization of Federal, State, local and private resources.
Responsibility for water quality monitoring and surveillance in the 208
study area lies with the U.S. Environmental Protection agency, the Corps of
Engineers, the Department of Environmental Quality, and local governments.
Currently the Corps of Engineers is conducting a sampling program at
Saylorville Lake by means of a contract with Iowa State University. The
purpose of the program is to monitor river and lake water quality conditions
and to relate physical, chemical and biological changes to physical river and
lake characteristics as well as the operational changes connected with the
Saylorville Dam project. The United Stated Geological Survey, under
contract with the Iowa Natural Resources Council, is conducting a monitoring
program in the Walnut Creek Basin to determine flow rates during high-flow
conditions.
-------
11—36
The State DEQ has primary responsibility for water quality monitoring
and surveillance. Its principal management tool is the State Operation
Permit Program, carried out in coordination with the National Pollutant
Discharge Elimination System (NPDES). The permit provides for discharge
effluent limitations in prescribed compliance schedules. The DEQ also
conducts on—site plant inspections to verify self-monitoring reports and
compliance with permit stipulations.
Municipalities and counties have power to provide drainage systems for
flood and other surface waters, sewage systems and wastewater treatment
plants. They also have the authority to require and regulate connections to
existing sewer systems.
Flood Hazards
The flood hazards in parts of the 208 study area have been very high -
particularly along the Raccoon and Des Moines Rivers and along Walnut and
Fourmile Creeks. The completion of Saylorville Reservoir will significantly
lessen the flood hazard throughout the area. The impact of alternative
release rates on downstream conditions is given in a detailed technical report
(u.s. Army Engineer District, Rock Island, 1975).
Des Moines is an eligible community under the National Flood Insurance
Act. Planning and other studies are now underway to develop a flood
management program consistent with the requirements of the Act.
While the completion of Saylorville Reservoir and certain aspects of the
developing areawide flood management plan will certainly affect water
quality and water quantity problems throughout the 208 study area, the
proposed 208 plan will not significantly increase or decrease flood hazard.
The proposed intermittent-point and non-point control strategies will have a
small effect of decreasing runoff and immediate discharge to area streams,
thereby lessening flood flows.
-------
11—37
Biology
Rare/Endangered Species
An interim list of endangered vascular plants (90 species), birds (six
species), mammals (eight species), reptiles and amphibians (eight species) and
fish (eight species) have been prepared for the State of Iowa under the
auspices of the State Preserves Advisory Board. (See Appendix A-2 for
complete species lists.) Not all species on these interim lists are found in the
Des Moines area, but many would have potential habitat areas in it.
Wildlife species become endangered when their native habitats are
either destroyed or altered significantly. Of the 90 endangered plant species,
approximately 40 percent require wetland habitats (including bogs, wet
meadows and standing water); approximately 30 percent require wooded sites;
and approximately 30 percent require either dry, exposed sites or prairie
sites. Wooded sites have always been limited, and agricultural development
has been especially disruptive to wetland and prairie sites in the area. (Many,
approximately two—thirds, of the endangered plant species in the State are
near the western and/or southern limit of their known natural geographical
range (Fernald, 1950), and may therefore be more sensitive to habitat
disruption than non-marginal species.)
Wildlife Habitats .
There are three principal types of wildlife habitats in the study area:
aquatic, semi-aquatic (or wetland) and terrestrial.
The major aquatic habitats are Big Creek Lake, Saylorville Lake (to be
completed in Spring, 1977), Dale Maffit Reservoir, Des Moines River and
various natural and artificial impoundments in its floodplain, Raccoon River
and various natural and artificial impoundments in its floodplain, Skunk River,
North and Middle Rivers, Beaver Creek, Walnut Creek and Four Mile Creek.
-------
11—38
Semi-aquatic or wetland habitats include Brenton Slough south of
Granger, the old stream channel of Skunk River (part of which is now included
in the Chicaqua Wildlife Area) and various temporary ponds in the floodplains
of the Raccoon and Des Moines Rivers.
Terrestrial habitats are scattered throughout the study area along river
and stream valleys. Some important examples are the land between Big
Creek Lake and Saylorville Lake, floodplain and side-slope forest areas along
the Des Moines River northwest and southeast of the City, Jester County
Park, Walnut Woods State Park and Denman Woods along the Raccoon River,
Margo Frankel Woods State Park, Thomas Mitchell County Park, Banner Mine
State Park and the Dale Maffit Reservoir park area. One privately owned
prairie remnant is located in the north-central part of the study area.
Natural, Terrestrial Vegetation and Associated Animals
The forests in the study area are a part of the eastern deciduous forest
type and are near its western limit (Braun, 1961). Probably less than one-half
of the original forest cover is left today. Woodlands lie principally along
rivers and streams. They are most commonly found on sloping ground or in
the floodplains of the larger rivers. The native vegetation of flatter upland
sites was that of prairie, with the strong possibility that fires either were
started in many instances to control the encroachment of prairies by forest
development or that such fires did so naturally (Curtis, 1959).
Three major plant community types can be recognized in the study area.
The first is the oak-hickory association found on upland, drier sites and
dominated by bur oak, white oak, red oak, shagbark hickory and butternut
hickory. This association is found on hilltops or south-facing slopes.
Understory species commonly found in this association are dogwood,
serviceberry, buckrush, gooseberry and chokecherry. Animals using this
forest association for at least part of their feeding and nesting requirements
-------
11—39
include several species of mice, squirrels, deer, fox, racoons, salamanders,
toads, doves, chipmunks, titmice, warbiers, woodpeckers, owls and vultures.
The maple-basswood association is dominated by bur oak, northern red
oak, basswood (linden), black maple and sugar maple. The association is found
on moist, well-drained sites generally on north- and east-facing slopes.
Understory species include dogwood, ironwood and buckrush. Animals using
this association for their habitat are not separable (at least on the basis of
information now available) from those using the oak-hickory association.
The floodplain-bottomland association is dominated by hackberry, black
walnut, elm, ash, boxelder, willows and cottonwood. It is found on land
immediately adjoining river and stream channels or their gravel deposits.
Red mulberry, greenbriar, virginia creeper and elderberry are found in the
understory. Animals found in this association include nuthatches, warbiers,
starlings, sparrows, woodpeckers, quail, hawks, frogs, salamanders, snakes,
toads, fox, squirrels, opossums and racoons. Where the forest continues, this
association gradually merges into the intermediate and upland associations.
Wetland Vegetation and Associated Animals
Wetland areas are found in the floodplains of the larger rivers and
streams in the study area, along the edge of larger lakes and reservoirs and in
poorly drained depressions. Dominant plant species are rushes, sedges,
cattail, arrowhead, willows, sycamore and cottonwood. These wetland areas
are used by many bird and animal species, including migratory species. Year-
round residents include beaver, muskrat, mink, mallards, teals, wood ducks
and lesser scaups. Migratory birds include Canada geese, blue and snow
geese, and diving and dabbling ducks (Belirose, 1968).
Terrestrial Animals Occupying Forest Edge and Open Habitats
While many of the animals mentioned above in connection with the
major forest associations also use forest edge and open habitats, the following
-------
11—40
species are more uniquely associated with forest and edge habitats: rabbit
(cottontail), woodchuck, bobwhite quail, ring-necked pheasant, ground squir-
rels, plains pocket gopher, western harvest mouse, prairie vole and meadow
vole.
Aquatic Plants
Phytoplankton is the dominant component of aquatic vegetation in the
rivers, streams, lakes and reservoirs of the study area. Rooted aquatics are
often found near water edges or in shallow, slow moving water bodies. The
most important component of phytoplankton communities are diatoms
(principally Cyclotella, Navicula and Synedra) . Blue-green algae (principally
Oscillatoria ) and green algae ( Scenedesmus ) are often present but seldom
dominant (Kilkus et.al., 1975). Populations of aquatic plants fluctuate
seasonally and with water quality and channel flow characteristics.
Aquatic Animals
Dominant fish in Lake Red Rock, Des Moines and Raccoon Rivers and
their tributaries are carp, river earpsueker, black crappie, black bullhead,
bigmouth buffalo and channel catfish. Other fish species include walleye
(stocked), bluegill, sunfish, northern pike (stocked), largemouth bass (stocked),
goldfish, yellow bass, white sucker and yellow perch (U.S. Army Engineer
District, Rock Island, 1975). Dominant invertebrates include caddis flies,
mayflies, mosquitoes, midges, stoneflies, crayfish, dragon flies and damsel
flies.
Crops and Managed Vegetation
The study area contains some of the most productive agricultural land
in the United States. In 1973 there were 281,505 acres of farmland in Polk
County with an average farm size of 209 acres and 31,311 acres of pasture
-------
11—41
(Iowa Crop and Livestock Reporting Service, 1975). Warren and Dallas
Counties have 334,914 and 352,521 acres of farmland respectively with
average farm sizes of 230 and 164 acres. The three major crops are corn,
soybeams and oats. Other crops include sorghum, wheat, rye, hay and seed
crops for hay species. Acreage and yields for the three primary crops in 1974
are shown below:
Acres Bushels/Acre
Corn Polk County 121,200 83.7
Warren County* 72,500 72.9
Dallas County* 152,400 79.6
Soybeans Polk County 83,100 24.7
Warren County* 52,800 23.0
Dallas County* 99,700 28.4
Oats Polk County 11 ,600 44.7
Warren County* 7,500 43.9
Dallas County* 5,200 56.7
Source: Iowa Crop and Livestock Reporting Service, 1975.
*Less than one-third of the land area in these counties is included
in the study area.
Air Quality
The major sources of air pollution in the study area are motor vehicles
and fossil fuel-burning power plants (Iowa Department of Environmental
Quality, 1973, p. 21-44). For this reason downtown Des Moines, parts of
eastern and northeastern Des Moines and the airport area are and will
continue to be problem areas. Fugitive dust, largely from unpaved roads and
other heavily used, unpaved areas, is also causing problems. All of Polk
County is currently included in a “maintenance plan area” for carbon
monoxide and suspended particulates. (The exact nature of control provisions
is yet to be determined.)
-------
11—42
Economic and Population Trends
Employment projections utilized in the 208 study call for employment
to increase from 142,000 in 1975 to 180,500 in 2000. (See Table 11—9.) The
projections are based on two sources of information: the Real Estate
Research Corporation’s study prepared for the City of Des Moines and
CIRALG, and the employment projections contained within the OBERS’ Series
E projections. These projections are described by major non-agricultural
employment categories below.
1. Manufacturing . Manufacturing employment would increase, but not
as rapidly as employment as a whole. As a percentage of total non-
agricultural employment, manufacturing employment would de-
crease from 18 percent to 16 percent by the year 2000.
2. Construction . Construction employment would show a modest
increase by the year 2000, with a significant increase in employ-
ment in Dallas and Warren Counties as population growth increases
in these areas.
3. Transportation and Public Utilities . Employment in this category
would continue to show no significant change, although small
increases would occur in Dallas and Warren Counties, consistent
with population increase.
4. Retail and Wholesale Trade . Employment in this category would
continue to increase as rapidly as employment as a whole. This
would result in an increase of over 25 percent in retail and
wholesale trade employment by the year 2000.
5. Finance, Insurance and Real Estate . This category is also expected
to show a significant increase, and at a rate greater than for
-------
11—4 3
Table 11-9
FUTURE EMPLOYMENT BY MAJOR EMPLOYMENT
CATEGORY IN THE 208 AREA
Employment (1000’s)
Major Employment Category 1975 1980 1990 2000
Manufacturing 26.0 27.0 28.3 29.7
Construction 6.7 6.9 7.7 7.9
Transportation & Utilities 10.0 9.9 10.1 10.1
Retail & Wholesale Trade 36.2 37.4 41.4 45.8
Finance, Insurance and
Real Estate 16.2 16.9 19.1 21.4
Services & Miscellaneous 26.1 28.0 33.1 39.2
Government 20.8 21.2 23.5 26.3
Total 142.0 148.9 163.2 180.5
Source: Real Estate Reserach Corp., 1973.
-------
11-44
employment as a whole, totalling 12 percent of non-agricultural
employment by the year 2000.
6. Services and Miscellaneous . Service employment is expected to
continue to show the highest rate of increase of any category,
growing by 50 percent by the year 2000 and replaceing manufactur-
ing as the second largest employment category.
7. Government . Governmental employment would continue to keep
pace with total employment and population increase, resulting in a
gain of nearly 25 percent by the year 2000.
Population projections for the 208 area estimate population to increase
from 315,000 in 1975 to 400,000 in 2000. These projections were made
following review of a variety of existing and relatively recent population
studies and a review of regional and local trends. The projected 2000
population of 400,000 is considered to be reasonably conservative, since it is
less than the OBERS Series E Projection of 414,000, a benchmark projection
utilized for water quality planning.
Land Use
Existing Land Use
Existing land use data for the Des Moines 208 area were described by 13
categories of land use based on the relationship between intensity of uses and
wastewater generation.
Major concentrations of urban development within the study area
consist of: (1) urban center including Des Moines and adjacent suburban
communities; (2) a number of free-standing satellite cities outside the urban
center; and (3) smaller cities located beyond the satellite cities. (See Plate
-------
PLATE 11-3
LAND USE 1975
EEl RESIDENTIAL - LOW DENSITY
(LESS THAN I D.U./ACRE)
RESIDENTIAL - MEDIUM DENSITY
L ___ J (1 TO 0.9 au/AcRE)
_____ RESIDENTIAL - HIGH DENSITY
(bR MORE aU/ACRE)
L....1 NON-RESIDENTIAL
LOW INTENSITY
NON-RESIDENTIAL
LOW INTENSITY (SPECIAL)
NON-RESIDENTIAL
MEDIUM INTENSITY
_____ NON-RESIDENTIAL
HIGH INTENSITY
I I CROPLAND
I I PASTURE FOREST & VACANT
[ _ j PERMANENT OPEN SPACE
_____ WATER
f FLOOD PLAIN
fl1 rE_IN M IL
0 1 2 4
CENTRAL IOWA REGIONAL ASSOCIATION
OF LOCAL GOVERNMENTS
K M KIRKHAM MICHAEL AND ASSOCIATES
HARLAND BARTHOLOMEW AND ASSOCIATES
AMERICAN CONSULTING SERVICES, INC
KIRKHAM TENECI-I ENVIRONMENTAL CONSULTANTS,
MICHAEL o INC CARLETON D. BEH AND COMPANY
PREPARAT D Of 11415 MAP PINA ’ !D I C1 .A A GRANT FROM OFT
45 E4 ‘NMfN’A PROTICI N A,,IN UNDER 50 IICN D l OP THE
RIDERAL WATER L’D DOE. NI*OD ADI A R\MLI.l5 DR FR?.
-------
11—4 6
11-3.) The area outside the urban center is predominantly agricultural land
interspersed with bands of pasture and forest lands.
Quantitatively, the overall pattern of existing land use within the study
area is dominated by non-urban uses with cropland accounting for nearly 70
percent of the present use. (See Table 11-10.) Urban uses account for less
than 10 percent of the total acreage.
Land Use Trends
The general development trends that are occurring in the 208 area
consist of: (1) development of suburban areas, primarily to the west of the
City of Des Moines; (2) development of satellite cities surrounding Des
Moines such as Ankeny, Altoona and Bondurant; and (3) the development of
areas oriented to Interstate 35-80 around the edge of the Des Moines urban
center.
The following development trends for land use sectors are occurring:
1. Agriculture . Almost all the county which is not in urban
development is utilized for agricultur . As urban development takes place
(and as speculative land investment in advance of development takes place),
land is removed from agriculture and put in a transitional holding state or is
developed. This is occurring primarily on the suburban fringe areas and on
the fringe areas of developing satellite cities.
2. Residences . Most residential development is taking place in the
following two areas: (1) the western suburbs of the urban center such as West
Des Moines and Urbandale, and (2) the satellite cities such as Ankeny,
Bondurant, Altoona and Norwalk. Some residential development is also taking
place in the unincorporated area, particularly in the corridor between Ankeny
and Des Moines and the corridor between Des Moines and Altoona. Only
-------
11—47
Table 11-10
LAND USE - 1975
Land Use Category Acres
1. Residential-Low Density
(Less than 1 dwelling per acre) 6,763
2. Residential-Medium Low Density
(1—3 dwellings per acre) 7,970
3. Residential- Medium High Density
(3—7 dwellings per acre) 13,820
4. Residential-High Density
(over 7 dwellings per acre) 2,253
5. Non-Residential-Light Intensity 5 ,525
6. Non-Residential-Light Intensity (Special) 780
7. Non-Residential-Medium Intensity 4,359
8. Non-Residential-High Intensity 210
9. Street 15,892
10. Cropland 350,850
11. Pasture, Forest and Vacant 78,730
12. Permanent Open Space 19,253
13. Water 6,437
Total 512,842
Source: Taken from land use prepared by individual communities,
aerial photos and field checks by C1RALG and HB&A.
-------
11-48
limited residential development is occurring in the outlying rural cities.
Within the central urban complex land uses of fairly high intensity have been
locating on the upper limits of water sheds creating problems in sanitary
sewer capacities where these were built to serve lower parts of these water
sheds a number of years ago.
3. Recreation Lands . All units of government are participating in the
development of recreational lands. The Federal government (Corps of
Engineers) is developing Lake Red Rock and Saylorville Lake. The State
operates two parks (Walnut Woods and Margo Frankel Park) and is developing
recreational resources at Big Creek Reservoir. Many communities are
acquiring or reserving land along the major rivers (as a part of their open
space program) using federal funds. Also, individual communities are
purchasing and developing parks to serve their local residents. Programs to
provide publicly owned open spaces along the Des Moines and Raccoon Rivers
are of particular significance.
4. Commerce . Very little retail commercial development is taking
place in the Des Moines Central Business District, although some offices are
being built. The majority of retail and office commerce is being developed at
suburban locations throughout the metropolitan area. In many cases this
commercial development consists of shopping centers or strip commercial
along major streets. Commercial development is taking place at locations
along 1—35-80 also. In the satellite cities, commercial development is
occurring along with residential development. In many cases the outlying
commercial development is in the upper parts of watersheds.
5. Industry . Most new industry is locating in planned industrial districts
in the urban center where utility service is available along with good
transportation connections. With 1-35-80 and 1-235 being the major elements
of the transportation system in the 208 area, much of the industrial
development is locating in close proximity to one of these highways. These
sites are at a considerable distance from any location for a central waste
treatment plant.
-------
11-49
Land Use Planning
The Intensity Development Pattern (Land Use Plan) for the Des Moines
208 area was selected following consideration of a number of alternatives
designed to highlight water quality options. The pattern reflects a projected
year 2000 population of 400,000 persons for the 208 area.
The Intensity Development Pattern was based on a continuation of
present policies of the individual local governmental jurisdictions as reflected
in their land use plans and zoning regulations, as adjusted to reflect areawide
trends and realities.
The resultant development pattern bears a general resemblance to
current urban patterns within the 208 study area. The urban “core” area
centered upon the City of Des Moines remains the major urban concentration
with the major extentions of growth generally occurring to the west and
north. The first ring of communities surrounding the urban “core” would
become increasingly urbanized and in some cases urban development along
corridors between the “core” and outlying communities would be intensified.
Future growth in the area would be primarily located in the urban
“core” and in incorporated outlying communities. Within the urban “core”,
Des Moines and Windsor Heights would increase in population by approxi-
mately eight percent while the western suburbs (Clive, Urbandale and West
Des Moines) would increase from their already substantial population base by
35 to 45 percent, and Pleasant Hill would add substantially to its smaller
existing population. The “core” area as a whole would attract nearly 50
percent of the total growth in the 208 study area. (See Table lI-il.)
All outlying communities would have substantial development, account-
ing for approximately 40 percent of the total growth. The largest growth
would occur in communities to the north and east of Des Moines (especially
-------
11—50
Table Il-Il
ANTICIPATED POPULATION TRENDS
Des Moines, Iowa 208 Area
1975 1975-2000 1975-2000
Estimated Estimated Population
Des Moines Urban Area Population Population Change
Des Moines 199,000 215,000 +16,000
West Des Moines 22,000 32,000 +10,000
Urbandale 17,000 26,000 + 9,000
Windsor Heights 6,500 7,000 + 500
Clive 5,500 8,000 + 2,500
Pleasant Hill 2,550 5,000 + 2,450
Sub—Total 252,550 293,000 +40,450
Cities in Metro Area
Ankeny 13,000 22,000 + 9,000
Altoona 4,150 11,000 + 6,850
Carlisle 2,750 4,000 + 1,250
Johnston 2,500 7,500 + 5,000
Norwalk 2,300 4,500 + 2,200
Waukee 1,800 3,300 + 1,500
Mitcheliville 1,500 2,500 + 1,000
Bondurant 1,250 3,000 + 1,750
Grimes 900 3,000 + 2,100
Granger 850 1,200 + 350
Polk City 850 1,200 + 350
Hartford 600 800 + 200
Runriells 350 700 + 350
Elkhart 250 350 + 100
Cumming 200 300 + 100
Spring Hill 130 150 + 20
Alleman 100 200 + 100
Sub-Total 33, ! 65,700 +32,220
Major Unincorporated Areas
Saylor Township 3,900 9,500 ÷ 5,600
Delaware Township 2,300 3,300 + 1,000
Bloomfield 2,300 3,500 + 1,200
Greenuield Plaza 1,500 2,000 + 500
Lakewood 1,200 1,500 + 300
Lovington 1,000 2,500 + 1,500
West Bloomfield 500 600 + 100
Sub—Total 12,700 22,900 +10,200
Balance of 208 Metro Area
Rural Non-Farm Remainder
of 208 Area 7,470 11,800 + 4,330
Rural Farm Remainder
of 208 Area 8,800 6,600 2,200
315,000 400,000 +85,000
Total
-------
11—51
Johnston, Ankeny, Altoona and Bondurant); somewhat less growth would occur
in outlying communities outside of the urban “core” area to the south and
west.
The unincorporated urban areas to the north and northeast of Des
Moines (Saylor and Delaware Townships) would attract growth as part of
developing urban corridors connecting Des Moines and the outlying “satellite”
communities. Additional growth in Saylor Township would be generated by
the prospect of recreational development adjacent to the Saylorville
Reservoir. Growth in unincorporated areas not now urbanized would be
drastically limited, although some shift in population from rural farm
residence to rural non-farm residence would be expected. This would result
in additional development in some unincorporated areas such as those
adjacent to the Saylorville Reservoir and in hilly areas southeast of Des
Moines.
South of Des Moines the trend in development in unincorporated areas
would continue to be primarily low-density residential uses along major roads
or in hilly areas unsuitable for cultivation. Total growth in the unincorpo-
rated areas would be approximately 12,000 persons, of which 80 percent
would be in urbanized areas; the increase in rural non—farm population would
be offset to some extent by continued loss in rural farm population.
Extent and Effectiveness of Current Land Use Planning
Land use planning is a broad term and represents many activities and
actions on the part of a community. For this analysis, the comprehensive
plans, zoning regulations and subdivision regulations have been used as
evidence of a local government’s role in land use planning.
Twenty of the 26 local jurisdictions, including the three counties, have a
comprehensive plan, ten of which were adopted in 1970 or later. (See Table
11-12.) Six of the jurisdictions are presently in the process of updating or
-------
11—52
Table 11-12
STATUS OF LAND USE PLANNING
Date of Zoning Subdivision
Comprehensive Plan Ordinance Regulations
1. Alleman 1974 * *
2. Altoona 1974 X X
3. Ankeny 1974 X X
4. Bondurant 1968* X X
5. Carlisle 1969 X X
6. Clive 1962* X X
7. Cumming
8. Des Moines 1963* X X
9. Elkhart X
10. Granger
11. Grimes X
12. Hartford X x
13. Johnston 1973 X X
14. Mitcheilville 1971 X X
15. Norwalk 1969* X X
16. Pleasant Hill 1972 X X
17. Polk City 1973 X X
18. Runnells 1972 * X
19. Spring Hill
20. Urbandale 1971 X X*
21. Waukee 1968* X X
22. West Des Moines 1968 X X
23. Windsor Heights 1970 X X
24. Dallas County 1963 X X
25. Polk County 1957* X X
26. Warren County 1961 X X
* Indicates an update or study currently being undertaken or considered.
Source: CIRALG.
-------
11—53
refining their plans. These plans formed the basis for the areawide Intensity
Development Pattern adopted for the 208 Plan. A major factor in the plans
relative to water quality is a widespread concern about the maintenance of
the floodway and adjacent flood-fringe areas along major streams (and to
some extent along lesser tributaries) by almost all jurisdictions, and
particularly Clive, Urbandale, Des Moines and West Des Moines.
Twenty of the 26 political subdivisions have zoning regulations and
seven are in the process of preparing regulations or revising existing
regulations. As would be expected, the ordinances vary from quite complex
to relatively simple and their utilization relative to community goals and
their administration varies as well.
Twenty-one of the jurisdictions have subdivision regulations and four
are preparing new or revised regulations. Most of the regulations are
standard in format and content. One jurisdiction has an ordinance requiring
control of soil erosion during construction.
Any evaluation of effectiveness of land use planning is relative. Land
use planning in the Des Moines 208 is similar to that in much of the midwest.
The largest city, Des Moines, has a sizable planning staff, and planning is an
important part of municipal policy. Most of the suburban communities place
a significant reliance on planning and zoning. Some of the smaller, more
rural communities utilize planning while others do not. Those municipalities
without staff may utilize (and many do) the resources of the regional agency
(CIRALG) which has a sizeable planning staff.
Administrative and Regulatory Land Use Controls Now In Effect
Both of the basic land use controls, zoning and subdivision regulations,
were mentioned in the previous section. A number of zoning techniques in
the area have an impact on water quality, and these are described below:
-------
11—54
1. Floodplain Regulations . Ten of the 26 jurisdictions have floodplain
regulations as a part of their ordinance. These regulations limit development
within the broad floodplain to open space uses such as agriculture and parks.
2. Planned Unit Development (PUD) Regulations and Site Plan Review .
Eight of the jurisdictions utilize planned unit development regulations in their
ordinances. These are of a variety of types from a broad PUD to planned
residential requirements. All require a site plan, development plan or some
other type of mechanism in the review process. In several instances site plan
review extends beyond the PUD process to major commercial or industrial
projects. Site plan review for individual uses is limited. Effect on water
quality is a consideration but not a major one in the review process.
3. Buffer Zones . A number of the ordinances identify buffer zones or
open space requirements. Generally, these are expressed in terms of
standards for various developments, although the West Des Moines ordinance
has specific buffer zone requirements.
4. Permits . All of the ordinances require permits as an administrative
enforcement procedure.
Other regulations besides zoning and subdivision regulations include the
following:
1. Building Codes . Most of the jurisdictions (18) have and enforce a
building code and have in-house inspection staff.
2. Septic Tank Regulations . All three counties regulate location of
septic fields through their Boards of Health. In each case, a permit is
required, soil porosity tests must be made, and locational criteria must be
met.
-------
11—55
3. Soil Loss Limits Regulations . The three soil conservation districts
(Polk, Warren and Dallas Counties) in the Des Moines 208 Study Area have set
soil loss limits in their districts pursuant to the conservancy district law. The
soil loss limits are site-specific and are expressed for each soil type in terms
of tons per acre per year lost from erosion using the Universal Soil Loss
Equation as a guide. Maximum allowable soil loss is in the vicinity of five
tons per acre per year.
Theoretically administration of the regulations occurs in the following
manner: Soil erosion can be declared a nuisance if it results in or contributes
to damage to any internal improvement of a conservancy district or damage
to property other than that of the owner or occupant of the land on which
such erosion is occurring. In either of these instances, action may be brought
by: (1) the Commissioners of the Soil Conservation District within which the
erosion occurs; (2) the owner or owners of any property so damaged; and (3)
the Board of the Conservancy District whose internal improvement is
damaged. Complaints are filed in writing with the Soil Conservation District.
The District Commissioners then investigate the complaints and determine if
soil loss limits are being violated. Notice of the Determination is given to
the owner or owners alleged to be in violation, and voluntary abatement of
the nuisance is sought. In case voluntary abatement does not take place, an
Administrative Order is issued by the District Commissioners to the parties
found to be in violation and they are advised as to the action required.
Generally, this will consist of preparation of an erosion control plan and the
following of practices in line with this plan to limit erosion. If the owner or
owners fail to initiate the necessary conservation work within the time
requirement, the District Court may be petitioned by the Commissioners to
issue a court order to obtain immediate compliance. If the owner or owners
do not comply they may be found in contempt of court and so punished.
The present experience with the soil loss limits regulations is limited
but growing. Since passage of the law and determination of the soil loss
-------
11—56
limits, five complaints have been filed which were settled out of court. Many
other problems have been solved prior to the filing of formal complaints.
Aspects of Development Trends That
Might Cause Adverse Environmental Effects
It is unlikely that any of the land development trends in the Des Moines
208 Area would significantly affect air quality. Control of industrial
emissions (which is good at the present time), emission controls on internal
combustion engines, and control of “fugitive dust” from unpaved surfaces will
be the major factors in air quality.
If development continues as at present and if major sewer system
improvements are not made, adverse environmental conditions which pres-
ently exist will continue. These would include: (1) overloading of sewers
from continuing development; (2) continued pollution from septic tanks in
unincorporated areas of the county such as the corridor between Ankeny and
Des Moines; (3) adverse effects on Saylorville Reservoir (when completed)
from urban development oriented to it; (4) adverse impacts on water quality
from expanding satellite centers with inadequate sewage treatment facilities;
and (5) adverse effect from urban development in the lowlands of the
Raccoon River or the Des Moines River.
In addition to the above, a major environmental effect of the continued
development will be the loss of agricultural land and agricultural products as
a result of removing high productivity agricultural lands from agricultural
production. (See Plate 11-5.)
Environmentally Sensitive Areas
Sources of Potable Water
The potable water source supplying the greatest number of people in the
study area is the lower Raccoon River and the alluvial aquifer system
-------
11—57
associated with it. At the present time approximately one-half of the water
is taken from the River directly aiid one-half is taken from infiltration
galleries buried in the aquifer (Johnson, 1976). Back-up facilities include the
Dale Maffitt Reservoir, at the Polk, Warren, Dallas and Madison County
intersection, which is charged by pumpage from the Raccoon River during
favorable flow conditions and discharged to the River under low flow
conditions. The other back-up system is a set of infiltration galleries
emplaced along the Des Moines River near the Raccoon confluence.
There are over 100 wells in use throughout the study area, one-half of
which penetrate to maximum depths of 400 feet below the surface.
Approximately one-third have depths of 400-500 feet with the remaining
wells deeper than 500 feet (data from well logs filed by Iowa Geological
Survey) Contamination of these welis by surface pollutants (such as nitrates,
for example) is a constant threat to shallow wells in agricultural 1 nd areas .
Deeper wells drilled in the urban areas for industrial use are less threatened
by surface contamination.
Surface Waters
Saylorville Lake, Lake Red Rock, Dale Maffitt Reservoir and the Lower
Raccoon River are the four most sensitive surface water resources in the
study area. While Lake Red Rock is not in the study area per se, it is and will
continue to be strongly influenced by the effectiveness of the overall water
quality management in the study area.
The two man-made lakes (actually reservoirs) collect waterborne soil,
nutrients and pesticides from agricultural land areas - particularly cropland.
If the rate of input from one or more of these parameters continues to be
high, euthrophication and/or aquatic life kills could increase and cause major
problems in the future. Lake Red Rock is also the primary sink for sediment
and stable toxic compounds released from the urbanized land areas in the
-------
11—58
study area. The wildlife and recreation of both Lakes depend critically on the
year-round maintenance of good water quality.
Wetlands
Brenton Slough (on Beaver Creek), parts of the Chicaqua Wildlife
Preserve (old channel of the Skunk River) and various shallow and temporary
pools in the floodplains of the Des Moines and Raccoon Rivers are the most
significant wetland areas.
Floodplains and Flood Retention Areas
The floodplain of the Lower Des Moines River is included in the 100-
year flood retention basin for Lake Red Rock. (See Plate 11-4.) Floodplains
for the Raccoon River, Middle River, Four Mile Creek, Beaver Creek and
Walnut Creek represent significant flood retention capacity in their respec-
tive basins and will cause increasing damage if developed for urban uses.
Groundwater Recharge Areas
The most significant groundwater recharge areas in the study area
overlie the alluvial aquifers along the major rivers and streams. (See Plate II-
4.)
Steeply Sloping Lands
These areas are limited to the sideslopes of the major river valleys.
(See Plate 11-4.)
Prime Agricultural Lands
(See Plate 11-5.)
-------
MAJOR
PLATE 11-4
ENVIRONMENTALLY
SENSITIVE AREAS
I 1 FLOOD-PRONE AREAS
I I SURFICIAL AQUIFERS
Il lIIfl BURIED CHANNEL AQUIFERS
STEEP SLOPES (14 AND OVER)
PASTURE, FOREST AND
VACANT LAND
GENERAL LOCATION OP SOUTHERN
LIMIT OF WISCONSIN GLACIER
SOURCES US. ARMY CORPS OF ENGINEERS,
U.SG , HARLAND BARTHOLOMEW A ASSOCIATES
IN MILES
2 4
cEis g CENTRAL IOWA REGIONAL ASSOCIATION
OF LOCAL GOVERNMENTS
KM
KIRK HA N
MICHAEL
KIRKHAM MICHAEL AND ASSOCIATES
HARLAND BARTHOLOMEW AND ASSOCIATES
AMFRICAN CONSULTING SERVICES, INC
TENECH ENVIRONMENTAL CONSULTANTS,
INC • CARLETON D. BEll AND COMPANY
PREPAIATION 31 1 14 15 MAP AA$ FINANCED THROUGH A GRANT FROM THE
US ENVIRONMENTAL PROTECTION AGENC’ UNDER SECTION 20$ OF THE
IIRA WATER POLLUTION CONTROL ACT AMENDMENTS OP 972
-------
PLATE 11-5
LAND CAPABILITY
FOR AGRICULTURAL USE
L I CLASS I AND CLASS II CAPABILITY
SOILS WHICH HAVE FEW LIM TATION5 FOR CULTIVATION
OR HAVE LIMITATIONS WHICH REDUCE THE CHOICE OF
CROPS/OR MODERATE CONSERVATION PRACTICES.
I I CLASS III TO CLASS VIII CAPABILITY
SOILS WHICH HAVE SEVERE LIMITATIONS THAT REDUCE
THE CHOICE OF CROPS 0* REQUIRE SPECIAL COPISERVAT-
ON PRACTICES OR BOTH. AND SOILS WHICH ARE NOT
SUITABLE FOR CULTIVATION
NOTE: SOIL CAPABILITIES ARE NOT SHOWN FOR
DEVELOPED AREAS.
SOURCES: U.S. DEPARTMENT OF AGRICULTURE,
SOIL CONSERVATION SERVICE.
flJ E IN MILE&J 1
cEsa CENTRAL IOWA REGIONAL ASSOCIATION
OF LOCAL GOVERNMENTS
KM
KIRKHAN
MICHAEL
KIRKHAM MICHAEL AND ASSOCIATES
HARI.AND BARTHOLOMEW AND ASSOCIATES
AMERICAN CONSULTING SERVICES INC.
TENECH ENVIRONMENTAL CON5ULTANTS
INC CARLETON D. BE t-I AND COMPANY
PREPARATION OP THIS MAP WAS FINANCED THROUGH A GIANT FROM THE
US ENVIRONMENTAL PROTECTION AGENCY UNDER SECTION 205 OF THE
FEDERAL WATER POLLUTION CONTROL ACT AMENDMENTS OP 1972
-------
11—61
Aesthetics
Much of the natural beauty in the study area is related to the meeting
of land and water. The floodplains and wooded slopes adjacent to the rivers
and streams of the area provide a scenic relief from the rolling plain which
dominates central Iowa. Furthermore, it is in the floodplains and surrounding
slopes where most of the woody vegetation can be found. Elms, cottonwoods,
and willows grow on the valley floors, and oaks and hickories grow on the
valley walls and ridges above the stream channels. Many of the parks in the
area are located in these meeting places of land and water and, therefore,
have the potential for preserving important aesthetic resources. The
management of these parks, as well as other lands bordering rivers, lakes and
streams, is crucial to the maintenance of these aesthetic resources. Perhaps
the most important element of good management in this respect is
maintaining a sufficient buffer zone of undisturbed land between the river
itself and the cultivated and developed land surrounding it. A river or stream
completely stripped of this buffer zone loses much of its natural beauty and
also enhances the rates of siltation of the waterway and erosion of the
channel.
The bluffs and ridges along the Des Moines River south of the City of
Des Moines might be considered an especially scenic area. This area is
particularly deserving of consideration in the form of adequate natural areas
between the stream channel and stream-side development of any kind. The
minimum width of the natural area necessary to protect the scenic value will
vary along the channel depending on the width and configuration of the
floodplain, the topography of the valley wall, and the character and density of
the vegetation along the channel.
Noise
Information on existing and projected noise levels is available primarily
in connection with specific highway construction and widening projects.
-------
11—62
Noise-generating land uses in the study area include interstate highways and
other auto/truck traffic thoroughfares; concentrations of streets as found in
downtown Des Moines and selected outlying areas; railroad switching areas;
the municipal airport; and plants producing heavy equipment, such as tractors
and heavy farm machinery. At the present time, there is not sufficient data
at the scale of the study area itself which would allow conclusions affecting
areawide planning. Location of any significant noise-generating operations in
connection with wastewater treatment will need to be made giving full
consideration to impact on residential or other noise sensitive land uses.
Radioactivity
There are 13 individual or organizations who are licensed to use
radioactive materials in the study area. All are located in the City of Des
Moines. Seven are for medical treatment purposes; six are for use in industry
and research. All licensees are required to keep complete records of their
acquisition, use and disposal of radioactive materials and present their
records for review by regulatory officials on request. The Iowa Department
of Environmental Quality is furnished with copies of license, privileges,
reports and other relevant documents.
The radioactive sources in the study area are not presently a significant
threat to its environmental quality (Haars, 1976).
-------
“I—i
CHAPTER III - ALTERNATIVES
General Analytical Approach to the
Development of Alternatives
Alternative areawide plans were developed in four stages
Stage one consisted of developing and screening sub-systems and
options for the control and reduction of continuous point sources of pollution,
intermittent point sources and non-point sources. At this stage the broadest
possible approach was taken to the solution of identified water quality
problems attributable to one or more pollution sources.
Stage two consisted of combining feasible sub-systems and options into
sub—plans, i.e., continuous point source sub-plans, intermittent point source
sub-plans and non-point source sub-plans.
Stage three consisted of systematically screening all sub-plans with
respect to seven weighted criteria. For each criterion, consultants prepared
detailed technical comments on each sub-plan and submitted them for
consideration by the Coordinating Committee of resident professionals and
private citizens, who carried out the actual screening. The Committee also
determined the weighting factors applied to each criterion.
Stage Four consisted of combining the screened sub—plans into eight
alternative areawide plans for final screening and selection. The same
criteria used in sub-plan screening were used here. The screening was again
carried out by the Coordinating Committee, aided by detailed technical
comments and discussion with the consultants.
Continuous Point Source Alternatives
Feasible Systems, Sub-systems and Options
Community Options - Des Moines
Wastewater Treatment Options
-------
111—2
1. trickling filter plants
2. activated sludge plants
3. other mechanical plants
a. oxidation ditches
b. rotating biological surfaces
c. synthetic media trickling filters
d. activated bio-filters
e. fine screening and filtration devices
f. chemical treatment
4. waste stabilization lagoons
5. private disposal systems
Sludge Treatment and Disposal Options
Treatment Options :
1. thickening by gravity sedimentation followed by dewatering or
digestion
2. chemical treatment followed by dewatering
3. anaerobic or aerobic digestion followed by dewatering
4. dewatering by vacuum filtration, pressure filtration, centrifuga-
tion or on drying beds and lagoons
Disposal Options :
1. landfill
2. incineration
3. land application
4. production of soil conditioners
Wastewater Reuse and Disposal Options
1. domestic (potable/non-potable)
2. industrial reuse
a. cooling water
b. boiler feed water
c. process makeup water
-------
111—3
3. agrictiitural reuse (irrigation)
4. recreation
a. irrigation of parks, golf courses, etc.
b. supplemental supply for lakes and reservoirs
5. groundwater recharge
Outlying Communities with Mechanical Treatment Plants (Altoona,
Ankeny, Grimes, Highland Hills, Mitcheliville, Pleasant Hill, Urbandale)
1. Upgrade existing plant
2. Abandon existing plant and build sewer connections to areawide
treatment plant or its collection system
Outlying Communities with Treatment Lagoon or Lagoon System
( Bondurant, Carlisle, Des Moines Area tlBtt Des Moines Area tIC ,
Elkhart, Greenfield Plaza, Granger, Lakewood, Norwalk, Polk City,
Waukee)
1. Expand existing lagoon or lagoon system
2. Abandon lagoon(s) and build sewer connection to treatment plant in
neighboring community
3. Abandon lagoon(s) and build sewer connection to areawide treatment
or its collection system
Industrial Options
Direct Discharging Industries (American Can Co., Firestone Tire and
Rubber Co., Hallett Construction Co., Marquette Cement Mfg. Co.,
Martin-Marietta Corp., Meredith Printing Corp., Peters Construc-
tion Co.)
1. continue with existing operation
2. provide closed ioop for recycling of cooling water or washing
water only - with minimal net discharge to receiving stream
Munici lly Treated Industries (Adams Laboratories, Inc., Amend
Packing, AMF Lawn and Garden Division, Anderson Erickson Dairy,
Armstrong Tire and Rubber Co., Beaver Valley Canning Co., Bookey
Packing, Can-Tex Industries, Cargill Inc., Chicago Rock Is’and and
Pacific Railroad, DeTray Plating, Diamond Laboratories, Eagle Iron
Works, Emery Plating, F.W. Means, Great Plains Bag Corp., Hiland
-------
111-4
Potato Chip., Iowa Fund, Inc., Iowa Power and Light Co., Lambert
Ice Cream Co., Massey-Ferguson Des Moines, Meredith Corp., Mid-
American Dairy, Mid-Continent Bottlers, National By-Products, Inc.,
Prairie Farm Dairy (Flynn), Swift Edible Oil Co., Union Oil Mid-Iowa
Truck Plaza, United Plating, Wilson and Company, Inc.)
1. continue with present system of discharge to municipal treat-
ment plants and ultimately to areawide plant
2. pre-treat wastewater and discharge to municipal treatment
plants (likely candidates include Anderson Erickson Dairy,
Cargill, Inc., Wilson and Co. Inc., Hiland Potato Chip, Bookey
Packing, Prairie Farm Dairy (Flynn), National By-Products, Inc.,
Mid-American Dairy)
3. use existing industrial treatment facilities for pre-treatment
and discharge to municipal treatment plants
4. upgrade existing treatment facilities
5. abandon all existing industrial treatment facilities and dis-
charge to municipal treatment plants
6. combine wastewater with that of neighboring industry(ies) and
discharge to areawide plant via new sewer connection
7. discharge cooling water directly to Des Moines River or other
receiving stream and discharge only process wastewater for
treatment
8. provide closed loop for recycling of cooling water or washing
water - with minimal net discharge to receiving stream
Feasible Sub-plans
Community Options
Des Moines . Three basic options were selected for treatment
facilities:
1. Improve and expand existing Des Moines main plant
2. Make minimum necessary improvements in existing Des Moines
main plant for interim period, during which new plant would be
constructed downstream. Existing plant would be abandoned in
stages over a period of approximately 10-15 years.
3. Construct new plant downstream and abandon existing plant as
soon as possible.
-------
111—5
Each of these basic treatment options was combined with the
following sub-alternates for transport and treatment of sewage
from Ankeny (west), Johnston, Urbandale, Beaver Creek Sanitary
District, Lovington, Saylor Township and Camp Dodge
1. Construct a north areawide treatment plant. The facility
would provide secondary treatment but not nitrification. It
would discharge to the Des Moines River near the northern
City Limit of Des Moines.
2. Pump flows to the East 20th Street interceptor of existing
collection system.
3. Pump flows to Four Mile Creek interceptor, which would be
constructed to a point at 2nd Avenue.
4. Transport flows by gravity south along Des Moines River in a
new interceptor which would be constructed to a point at 2nd
Avenue.
Alleman
1. Abandon septic tanks. Build collection system and construct
lagoon.
2. Maintain septic tanks. Intercept drainage from existing
discharge pipe. Construct interceptor and lagoon.
Carlisle
1. Upgrade existing lagoon.
2. Abandon lagoon and discharge to areawide plant
Cumming
1. Abandon septic tanks. Build collection system and lagoon.
Elkhart
1. Upgrade existing lagoon.
Granger
1. Upgrade existing lagoon.
Grimes
1. Upgrade existing treatment plant.
-------
111—6
Hartford
1. Abandon septic tanks, build collection system and construct
lagoon.
Mitcheliville
1. Abandon existing plant, construct trunk to new lagoon down-
stream on Camp Creek.
Norwalk
1. Upgrade existing lagoon.
2. Upgrade existing lagoon. Build an outfall sewer for the
northern part of Norwalk and discharge to the Lakewood
lagoon.
Polk City
1. Upgrade existing lagoon.
Spring Hill
1. Abandon septic tanks. Build collection system and lagoon.
Waukee
1. Upgrade existing lagoon.
Industrial Options
Direct Discharging Industries (American Can Co., Firestone Tire
and Rubber Co., Hallett Construction Co., Marquette Cement Mfg.
Co., Martin-Marietta Corp., Meredith Printing Corp., Peters
Construction Co.)
1. continue with existing operation
2. provide closed ioop for recycling of cooling water or washing
water only - with minimal net discharge to receiving stream
Municipally Treated Industries
Anderson Erickson Dairy, Cargill, Inc., Wilson and Co. Inc.,
Hiland Potato Chip, Bookey Packing, Prairie Farm Dairy
(Flynn), National By-Products and Mid American Dairy:
-------
III—?
pre-treat as required by respective wastewater character-
istics and discharge to areawide plant
Adams Laboratories, Inc .
1. continue with existing facilities to meet effluent limita-
tions
2. discharge via new gravity sewer in Walnut Creek to Des
Moines main plant and ultimately to areawide plant
3. pump to Waukee for treatment
4. use existing treatment facilities for pre-treatment and
discharge to Des Moines or Waukee for treatment
Armstrong Tire and Rubber Company
1. continue with existing discharges
2. run a common pipe directly to Des Moines River for
discharge of cooling water (could be combined with that
of Chicago Rock Island and Pacific Railroad)
3. provide closed ioop for recycling cooling water - with
minimal net discharge to Des Moines River.
Beaver Valley Canning Company
1. continue with existing treatment and discharge
2. discontinue discharge of cooling water to Grimes treat-
ment plant and discharge directly to stream
3. use lagoons for pre-treatment and discharge to areawide
treatment plant
Can-Tex Industries
1. continue with existing treatment system
2. discharge to areawide treatment plant
Chicago Rock Island and Pacific Railroad
1. continue with existing treatment process
2. discharge skimmed effluent to Des Moines River
-------
111—8
3. discharge skimmed effluent to areawide treatment plant
4. provide closed loop for recycling of washing water - with
minimal net discharge to Dean Lake
Crossroads U.S.A., Incorporated
1. continue with existing treatment system
2. discharge to areawide treatment plant
Iowa Fund, Incorporated
1. upgrade existing lagoon to meet controlled discharge
standards
2. develop joint treatment system with Mid-Continent Bot-
tlers
3. discharge to areawide treatment plant
4. use existing lagoon as for pre-treatment and discharge to
joint treatment system or areawicle system
Iowa Power and Light Company
1. continue with present operation
2. continue with present disposal of fly ash slurry and seal
water but abandon septic tank and discharge to areawide
treatment plant
3. provide closed ioop for recycling cooling water with
minimum discharge to Des Moines River
Mid-Continent Bottlers
1. upgrade existing lagoon to meet controlled discharge -
standards
2. develop joint treatment system with Iowa Fund, Incorpor-
ated
3. discharge to areawide treatment system
4. use existing lagoon for pre-treatment and discharge to
joint treatment system or areawide system
-------
111—9
Union Oil Mid-Iowa Truck Plaza
1. continue with present operation and chlorinate effluent
2. abandon existing treatment facility and discharge to
areawide system
3. utilize existing polishing pond for pre-treatment and
discharge to areawide system
Preferred Sub-plans
Based on extensive and systematic screening procedures, the Coordinat-
ing Committee selected two continuous point-source sub—plans for further
development and combination into areawide alternate plans.
Sub-plan L Expand and upgrade existing Des Moines main plant to
make it suitable as an areawide treatment plant serving
all urbanized areas except 12 outlying communities.
Transport flows from the seven north area communities
along Des Moines via new gravity sewer constructed to a
point at 2nd Avenue. The options for outlying communi-
ties and industries were not refined or modified beyond
the stage described under “Feasible Sub-plans” above.
Sub-plan Construct a new areawide treatment plant in the general
vicinity of the existing Des Moines main plant. (The same
as sub-plan I in all other respects.)
Intermittent Point Source Alternatives
Feasible Systems, Sub-systems and Options
Combined Sewer Discharges
1. Continue present operation and maintenance programs for the
combined sewer system.
-------
Ill—i 0
2. Remove storm sewer inlets from combined sewer system (partial
separation).
3. Construct relief sewers in those areas where the downstream
capacity of the existing combined sewer system is inadequate to
carry combined flows. The relief sewer would discharge either to
a treatment facility or to an existing sewer system which has the
capacity for additional flows.
4. Construct off-line storage for excess flows. The stored flow would
either be pumped back to the system during low-flow periods or
treated directly in the storage facility and discharged to a suitable
receiving stream.
5. Construct direct treatment facilities for combined sewer over-
flows. These facilities would be either at individual overflow
points or at a centralized treatment facility. Treatment could be
provided by:
a. conventional treatment (physical, biological, disinfection)
b. high-rate micro-screening followed by disinfection
c. disinfection only
d. mechanical flow separation (e.g. flow-activated centrifugal
flow separators)
6. Develop source control measures, such as street cleaning, erosion
control, etc.
7. Develop resource conservation measures, such as use of treated
combined and storm sewer effluents in one or more domestic,
industrial, agricultural, recreational or groundwater recharge appli-
cations.
8. Other:
a. increase existing maintenance program
b. improve hydraulic characteristics
c. increase storage and treatment during storm flow conditions to
the greatest possible extent.
Storm Sewer Discharges
1. Continue present operation and maintenance program for the storm
sewer system.
-------
“I—li
2. Provide storage facilities (either surface or sub—surface). Flows
would be held in storage for subsequent slow release to stream or
storm sewer or held for possible reuse.
3. Direct treatment of storm sewer discharge
a. conventional treatment, including physical and biological
methods followed by disinfection
b. high-rate micro-screening followed by disinfection
c. disinfection alone
d. mechanical flow separation (e.g. flow-activated centrifugal
flow separators)
4. Source control options such as street cleaning, erosion control, etc.
5. Resource conservation measures, such as use of treated effluents in
one of more domestic, industrial, agricultural, recreational or
groundwater recharge applications.
Feasible Sub-plans
Combined Sewer Discharges
1. Continue with present operation and maintenance program with
emphasis on implementing source control options.
2. Construct flow separators at overflow points.
3. Remove storm sewer inlets from combined system and divert storm
discharges to new or existing storm sewer (partial separation).
4. Provide for storage detention and subsequently discharge to
treatment facility or provide treatment in detention facility itself.
5. Segregate sewer systems and provide separate sewer lines to
transport flows to treatment facility(ies).
6. Maximize storage capacity in existing and new transport and
treatment facilities.
Storm Sewer Discharges
1. Continue with present operation and maintenance program with
emphasis on implementing source control options.
-------
111—12
2. Construct flow separators at overflow points.
Preferred Sub-plans
1. Segregate sewer systems and provide separate sewer lines to
transport flows to treatment facility. The facilities required for
implementing this sub—plan are included in the transportation
segment of both preferred point source sub-plans. Only minimal
modifications would be required to accommodate needs of inter-
mittent point source control strategy.
2. Construct flow separators at combined and storm sewer overflow
points.
Non-point Source Alternatives
Feasible Systems, Sub-systems and Options
Existing Landfills and Dumps
1. groundwater diversion using tile drains
2. groundwater diversion by slurry trenching
3. pond treatment of leachates
Cropland Runoff
1. no-till planting
2. conservation tillage practices
3. contouring
4. conversion of erosible lands to pasture
5. reduction of fall plowing
6. use of turf cover in natural swales and waterways
7. terracing
8. site-specific erosion control structures
Animal Feeding Operations
1. diversion berms
-------
111—13
2. fences and/or supplemental plantings along waterways
Construction Sites
1. scarification
2. tracking
3. interception and diversion structures
4. vegetative stabilization
5. use of mulches on excavated surfaces
7. rip-rapping
8. use of gabion dams
9. construction of sediment basins
10. use of gravel inlet filters
Urban Storm Runoff Control
1. increase frequency of street sweeping
2. use of grass linings in drainage channels
3. pave unpaved roads
4. chemically treat unpaved roads
5. speed control on unpaved roads
6. regular cleaning of catch basins after storms
Feasible Sub-plans
1. continue with existing practices for all categories of non-point
source pollution.
2. promote cropland runoff control options and continue with existing
practices for all other categories
3. sub—plan 2 plus increase frequency of street sweeping
4. sub—plan 3 plus enforcement of ordinances controlling construction
site practices
-------
111-14
5. sub—plan 4 plus a special control on the development of agricultural
land for urban uses
6. all provisions of sub-plan 5 except the promotion of additional
cropland runoff options (see sub-plan 2) beyond present trends and
programs
Preferred Sub-plans
1. Promotion of cropland runoff control options via financial support
for permanent soil and water conservation control measures such
as:
a. conservation ti liage practices
b. no-till planting
c. conversion of erosible lands to pasture
d terracing
e. site-specific erosion control structures
f. contouring
Options of secondary importance are reduction in fall plowing and
use of grassed (turf) waterways.
2. Sub-plan 1 described above, enforcement of construction site
control ordinances, and explicit controls designed to limit the
conversion of agricultural to urban uses
Areawide Plans
The six technical subplans which have been classified as feasible
subplans have been combined into eight alternative areawide plans. The six
technical subplans have been described in detail in previous sections of this
report. The facilities plans for the outlying communities will be the same,
regardless of which alternative areawide plan is selected as the final plan.
For the following outlying communities, existing lagoon systems would be
expanded to provide for controlled discharge:
(1) Carlisle
(2) Elkhart
(3) Grangér
(4) Norwalk
(5) Polk City
-------
111—15
The following communities would construct collection systems and
controlled discharge lagoons:
(1) Alleman
(2) Cumming
(3) Hartford
(4) Spring Hill
Waukee would upgrade its existing aerated lagoon system by adding
additional storage and installation of a rock filter for effluent polishing.
Mitcheilville would abandon its existing mechanical plant and construct
aerated controlled discharge lagoon facilities. Grimes would remain as a
continuous discharger and upgrade its existing mechanical plant and lagoon
system. A 201 Facility Plan for Runnells has been completed and is on file.
The plan recommends the construction of a collection system and a
mechanical treatment facility. Descriptions of the eight alternative
areawide plans are presented in the following sections. Table 111-1
summarizes the costs of the eight alternative areawide plans.
Alternative Areawide Plan 1: Expansion of the Existing Des Moines
WWTP,Segregation of Combined Sewers, Promotion of Cropland Runoff
Control Options, and Possible Increases in Street Sweeping
The plan calls for an expansion of the existing Des Moines WWTP
service area. Flows from Camp Dodge, Lovington, Urbandale - Beaver
Creek, Johnston, Saylor Township and West Ankeny would be transported
along the west bank of the Des Moines River. Flows from East Ankeny,
Altoona, Bondurant, Delaware Township, and Pleasant Hill would be conveyed
by gravity along Four Mile Creek. Flows from West Bloomfield, Lakewood,
Highland Hills, Greenfield, Areas B and C, and Bloomfield would be
transported to the Des Moines WWTP by two lift stations, force mains, and
-------
111—16
Table Ill-i
COMPARISON OF AREAWIDE PLANS
ANNUAL COSTS (S MILLIONS)
Des Moines, Iowa 208 Area
Capital Operation and Maintenance
Non- Point
Areawide Point Non-Point Intermittent Point Sources Intermittent
Plan Sources Sources Sources Sources Street Sweep Sources Total
$ .858(1)
1.783(2) 54.830(4)
.231(3) $2.50 $ 0 .329(5) $1.34 $ 0 511.871
.858
1 783 4.830
.231 2.75 0 329 1 34 0 12.121
858
1.783 4.830
.231 2 50 .329 329 1.34 .056 12.255
.858
1.783 4.830
.231 2 75 .329 329 1 34 .056 12.506
858
1 943 4.519
.231 2.50 0 329 1.34 0 11 720
.858
1 943 4.519
231 2.75 0 .329 1.34 0 11.970
.858
1.943 4 519
231 2.50 329 .329 1 34 .056 12.105
.858
1.943 4 519
.231 2 75 329 .329 1.34 .056 12.355
Due to the fact that the construction necessary for the segregation of combined and separated sewer system is an integral part of
the point source subplans and, therefore, included in their total cost, no cost for segregation has been shown under intermittent source
costs.
(1) Annual Capital Cost of Sewer Collection Systems for Johnston, Lovington, Delaware Township. Saylor Township and Bloomfield Service Areas
(2) Annual Capital Cost for Interceptors, Equalization & Treatment Plant for the Integrated Community Area
(3) Annual Capital Cost for Interceptors and Treatment for Outlying Community Area
(4) Annual Operation and Maintenance Cost for Integrated Community Area
(5) Annual Operation and Maintenance Cost for Outlying Corn murities
-------
111—17
gravity sewers. The existing De3 Moines WWTP would be expanded to serve
an estimated year 2000 population of 362,000 and a peak hydraulic flow of
165 MGD.
The sanitary flow from the northwest Des Moines area, Camp Dodge,
Lovington, Urbandale - Beaver Creek, Johnston, Saylor Township and West
Ankeny would be segregated by routing the flow through a new interceptor
sewer which is to be constructed parallel to the Westside Interceptor. The
Westside Interceptor presently receives flow from combined sewers. Flow
from the combined system would enter the main outfall to the plant up to a
point where the dilution ratio of the combined flow system is 5 to 1. Flows in
excess of 5 to 1 would be diverted to the combined sewer discharges.
Non-point source control within this plan is provided by a subsidy
program for cost sharing on cropland runoff controls and possible increases in
street sweeping for Des Moines residential areas and residential arterials. The
cost-sharing subsidy program would result in the construction of all needed
terraces and grade stabilization structures by the year 2000. The proposed
increase in street sweeping would result in fairly uniform residential cleaning
within the metropolitan area.
Alternative Areawide Plan II: Expansion of the Existing Des Moines WWTP,
Segregation of Combined Sewers, Promotion of Cropland Runoff Control
Options, Possible Increases in Street Sweeping, Construction Site Control
Option Enforcement through Ordinances, and Controls to Limit the Urban
Development of Agricultural Land
This plan is similar in all respects to Plan I except that in addition to
cropland runoff options and increased street sweeping for non-point source
control there would also be passage and enforcement of ordinances to control
erosion and sedimentation from construction sites and controls to limit the
rate and extent of urban development of agricultural land. The latter could
be carried out through county zoning actions.
-------
111—18
Alternative Areawide Plan III: Expansion of the Existing Des Moines WWTP,
Segregation of Combined Sewers, Flow Separators for Combined Sewer
Overflows and Strategic Storm Sewer Discharges, Promotion of Cropland
Runoff Control Options, and Possible Increases in Street Sweeping
This plan is similar in all respects to Plan I except that in addition to
segregation of combined sewers for intermittent point source controls, flow
separators would be constructed at each of the combined sewer overflows and
at strategic storm sewer discharge points for the removal of significant
fractions of grit, settleable solids, and floatable solids in the respective
flows. In this way, the combined sewer overflows and storm sewer discharges
would receive a degree of physical treatment before being discharged to the
receiving streams.
Alternative Areawide Plan IV: Expansion of the Existing Des Moines WWTP,
Segregation of Combined Sewers, Flow Separators for Combined Sewer
Overflows and Strategic Storm Sewer Discharges, Promotion of Cropland
Runoff Control Options, Possible Increases in Street Sweeping, Passage and
Enforcement of Ordinances for the Control of Erosion and Sedimentation
from Construction Sites, and Controls to Limit the Urban Development of
Agricultural Land
This Plan is similar to Plan I except that flow separators would be
constructed at each of the combined sewer overflows and at strategic storm
sewer discharge points for additional intermittent point source control; and
that ordinances would be passed and enforced to control erosion and
sedimentation from construction sites and controls made to limit the rate and
extent of urban development of agricultural land. The latter could be carried
out through county zoning actions.
-------
111—19
Alternative Areawide Plan V: Construction of a New Des Moines WWTP,
Segregation of Combined Sewers, Promotion of Cropland Runoff Control
Options, and Possible Increases in Street Sweeping
This plan calls for an expansion of the existing Des Moines WWTP
service area. Flows from Camp Dodge, Lovington, Urbandale - Beaver Creek,
Johnston, Saylor Township and West Ankeny would be transported along the
west bank of the Des Moines River. Flows from East Ankeny, Altoona,
Bondurant, Delaware Township, and Pleasant Hill would be conveyed by
gravity along Four Mile Creek. Flows from West Bloomfield, Lakewood,
Highland Hills, Greenfield, Areas B and C, and Bloomfield would be
transported to the Des Moines WWTP by two lift stations, force mains, and
gravity sewers. The existing Des Moines WWTP would be abandoned and a
new treatment facility would be constructed immediately east of the present
site. The year 2000 service population would be 362,000 and the peak
hydraulic flow through capacity would be 165 MGD.
The sanitary flow from the northwest Des Moines area, Camp Dodge,
Lovington, Urbanclale - Beaver Creek, Johnston, Saylor Township and West
Ankeny would be segregated by routing the flow through a new interceptor
sewer which is to be constructed paralled to the Westside Interceptor. The
Westside Interceptor presently receives flow from combined sewers. Flow
from the combined system would enter the main outfall to the plant up to a
point where the dilution ratio of the combined flow system is 5 to 1. Flows in
excess of 5 to 1 would be diverted to the combined sewer discharges.
Non-point source control within this plan is provided by a subsidy
program for cost sharing on cropland runoff controls and possible increases in
street sweeping for Des Moines residential areas and residential arterials.
The cost-sharing subsidy program would result in the construction of all
needed terraces and grade stabilization structures by the year 2000. The
proposed increase in street sweeping would result in fairly uniform residential
cleaning within the metropolitan area.
-------
111—20
Alternative Areawide Plan VI: Construction of a New Des Moines WWTP,
Segregation of Combined Sewers, Promotion of Cropland Runoff Control
Options, ,Possible Increases in Street Sweeping, Passage and Enforcement of
Ordinances to Control Erosion and Sedimentation from Construction Sites,
and Controls to Limit the Urban Development of Agricultural Land
This plan is similar in all respects to Plan V except that in addition to
cropland runoff control and increased street sweeping options for non-point
source control there would also be passage and enforcement of ordinances to
control erosion and sedimentation from construction sites and controls to
limit the rate and extent of urban development of agricultural land. This
could be carried out through county zoning actions.
Alternative Areawide Plan VII: Construction of a New Des Moines WWTP,
Segregation of Combined Sewers, Flow Separators for Combined Sewer
Overflows and Strategic Storm Sewer Discharges, Promotion of Cropland
Runoff Control Options, and Possible Increases in Street Sweeping
This plan is similar in all respects to Plan V except that in addition to
segregation of combined sewers for intermittent point source controls, flow
separators would be constructed at each of the combined sewer overflows and
at strategic storm sewer discharge points for the removal of significant
fractions of the grit, settleable solids and floatable solids in the respective
flows. In this way, the combined sewer overflows and storm sewer discharges
would receive a degree of physical treatment before being discharged to the
receiving stream.
Alternative Areawide Plan VIII: Construction of a New Des Moines WWTP,
Segregation of Combined Sewers, Flow Separators for Combined Sewer
Overflows and Strategic Storm Sewer Discharges, Promotion of Cropland
Runoff Control Options, Possible Increases in Street Sweeping, Passage and
Enforcement of Ordinances to Control Erosion and Sedimentation from
Construction Sites, and Controls to Limit the Urban Development of
Agricultural Land
-------
111—21
This plan is similar to Plan V except that flow separators would be
constructed at each of the combined sewer overflows and at strategic storm
sewer discharge points for additional intermittent point source control; and
that ordinances would be passed and enforced to control erosion and
sedimentation from construction sites and controls instituted to limit the rate
and extent of urban development of agricultural land. The latter could be
carried out through county zoning actions.
Selection of Preferred Technical Areawide Plan
The eight technical alternative areawide plans were systematically
screened by the Coordinating Committee with the benefit of detailed
comments from the consultants in the following seven areas: (1) detailed
costs; (2) environmental effects; (3) goal attainment; (4) operability,
reliability and flexibility; (5) public acceptability; (6) implementation feasibil-
ity; and (7) waste load characteristics.
Prior to the actual selection of the preferred plan, the Committee
removed the option of increasing street sweeping from all eight alternative
plans because they judged its costs not justifiable in light of the probable
benefits.
After group discussion of technical comments in each of the seven areas
listed, each member of the Coordinating Committee assigned a score of 1
through 10 to each of the areawide alternative plans for each criterion (1
indicates worst alternative; 10 indicates best). The average value of the
assigned scores in each area of evaluation was multiplied by the weighting
factor selected earlier by the Committee, and the final sum of products for
all areas was used as an indicator (though not the final decision) of
preference.
Committee balloting, discussion and final action led to the selection of
Alternative VIII.
-------
111—22
Alternate Management Plans
As soon as the work on the 208 Program reached the point where it was
possible to obtain a concept of the basic problems in regard to the point, non—
point and intermittent point systems, the Management Committee initiated
its work to develop a management plan capable of carrying out the 208
program as it was evolving. The Management Committee’s work was initiated
with a very broad approach.
Requirements for a management plan may be obtained from examina-
tion of the Public Law 92-500, the Federal Regulations concerning it, and the
Federal Guidelines for Development of Management Plans under the 208
Program. A study of this material indicated that for the most part the
individual cities and counties within the 208 area had adequate power
individually to carry out a 208 wastewater management program. However,
no areawide wastewater management program developed. In order that
resources could be assembled on an area-wide basis to be applied to the
solution to areawide wastewater problems as required by the 208 program, it
was evident to the committee that it would be necessary to form a new
areawide organization to meet 208 requirements.
It was at this point that the committee began its consideration of the
various options for creating a new areawide organization.
The point source discharge problem can be divided into two parts.
Initially there was a central system serving Des Moines and the immediately
adjacent areas including those which could be reached by trunk sewers and
connected to the central system in the future. Beyond the ICA in the
remaining parts of the 208 area, there are mostly agricultural uses and 13
communities referred to as “outlying communities”. Studies indicate that it
would not be economically feasible to bring the outlying communities into the
central system.
-------
111—23
Intermittent point-source pollution problems consist primarily of the
combined sewers within the City of Des Moines. However, this is not entirely
a City of Des Moines problem since communities north of the City of Des
Moines will become involved in this problem as plans are considered to
transport their sewage along the river to a common treatment plant.
EPA standards indicate the 208 programs must deal with both urban and
rural stormwater runoff problems. Many of these appeared to require some
type of areawide coordinated approach if they were to be solved.
In analyzing the basic problems presented and the need for some type of
an areawide approach to their solution, the committee came to the conclusion
that there were three basic approaches.
1. Develop an inter-agency agreement (probably under Chapters 28E
and F) and an areawide wastewater agency (AWA) and charge it
with effecting the necessary coordination of action on the part of
the 23 cities and three counties, with doing the continuous 208
planning that is required, and establishing priorities and under-
taking general activities of this nature. Point source problems
could be solved by an extension of the systems developed in the
past, i.e., by inter-agency contracts with the City of Des Moines,
and the point-source system developed under this type of an
arrangement.
2. Under existing or under new legislation a new areawide agency
could be established which in addition to the planning, coordination
and priority setting described under Option 1 above, could itself
undertake the provision of wastewater treatment and possibly
transportation of major wastewater quantities, i.e., trunk sewers,
into the central treatment plant. Thus, there would be a planning
and coordinating agency as well as an operating agency. Such an
-------
111-24
agency could contract with the outlying communities or with other
cities and counties with the outlying communities or with other
cities and counties for providing such additional services as all
wastewater collection and treatment, storm drainage and such
other activities that are a part of the 208 program as might be
appropriate from time to time.
3. The third concept would be to create a new AWA by new legislation
which would in effect create a new agency for the 208 area. This
could give the AWA in addition to the planning, coordination and
priority setting activities, the collection and treatment activities
within the ICA and full responsibility for all water quality problems
in the 208 area. Such an agency could be governed by a Board that
would be elected by the voters, could be appointed by the
Governor, or could be selected by the 26 cities and counties.
Options
Under the three concepts there were a number of categories of options
that the management committee examined including the following:
Geographic Jurisdiction . The 208 area could be left alone, it could be
modified slightly to adjust its boundaries more closely to the watersheds, or it
could be reduced in area significantly, possibly down to the ICA area with the
remaining area in effect turned back to the Iowa DEQ.
Participation and Control as previously mentioned could be by the cities
and counties through some type of proportionate representation, could be
directly by the voters or by a Board appointed by the Governor.
Functions of such an agency could include the planning, priority setting
and coordination activities, particularly in regard to regulatory measures
utilized for control of non-point sources of pollution wastewater treatment,
-------
I 111—25
sanitary trunk sewer system, and then a number of other possible activities
including storm sewer trunks and laterals, monitoring of water quality,
sanitary sewer laterals, and even water supply.
Financing involves consideration of a number of options. User charges
to the cities and counties were considered as were user charges to the
individual users, assessments to benefited property, ad valorum taxes, issuing
of revenue bonds and general obligation bonds, and issuing of short-term debt
instruments.
Ownership of the facilities became an important consideration. Under
various options this could be the areawide agency, by the cities and counties
individually, or by the cities and counties with undivided interests.
Planning, Coordination and Monitoring could be done by the areawide
agency or partly by the areawide agency, partly by the cities and counties,
and partly by the Iowa DEQ.
Operation and Maintenance of facilities could be partly by the areawide
agency, partly by the cities and counties, all by cities and counties, or all by
the areawide agency.
There are a possible 77,760 management plans that may be considered
by combinations of these concepts and options. The committee began its
sutdy by deciding to reduce this number by first discussing the various
concepts, their advantages and disadvantages, and then relating these to the
various options for organization, activities, and responsibility. These
discussions resulted in the elimination of certain concepts as well as certain
options. When the committee had agreed upon the most desirable options
regarding the activities and functions of an AWA, it then went back and
reconsidered the various concepts that might be used for an organization to
handle what appeared to be the needed type of areawide activities. This
-------
111—26
brought about a reduction of management plans to two basic families of
alternatives with four possible options under each one. These are described in
detail in the memorandum developed by the staff for the January 5, 1977
technical and management committee meetings. However, the basic features
of the alternates are as follows.
Alternate I Family
The Alternate I family of management plans make as small an
adjustment as possible to the existing situation as required to comply with
208 requirements. Fundamentally, this alternate is based upon an areawide
agency that would be charged with planning, monitoring, programming, and
priority setting only. All other wastewater programs would be undertaken
and financed by the individual units of local government.
Alternate IA . Alternate IA would be a new AWA organization created
under section 28E and 28F of the Iowa Statutes by a new agreement effected
between the 26 cities and the three counties in the 208 area.
Alternate TB . Alternate TB would call for the City of Des Moines to
undertake the coordination, planning, priority-setting activities assisted by an
advisory committee composed of representatives of the other units of
government.
Alternate IC . Alternate IC would be quite similar to Alternate lB
except that the activity would be undertaken by the Des Moines Water Board.
Alternate ID . Alternate ID would be similar to Alternate IA but would
consist of a modification of the existing inter-governmental agreement which
established the Des Moines sewer planning policy and technical committees.
This would be amended to provide for the necessary continued planning
coordination and priority setting as required under the 208 program.
-------
111—27
Alternate II Family
The Alternate II family would give the AWA certain construction and
operation functions in addition to the planning, coordination and priority-
setting. Under this family of alternatives, there would be some form of
transfer of ownership of existing facilities from local governmental jurisdic-
tions to the new agency.
Alternate hA . Under Alternate hA the AWA would undertake the
construction, financing, operation and maintenance of the trunk sanitary
sewers and the treatment facilities in the ICA. Similar services could be
provided to outlying communities under voluntary agreements. A sample
plan was developed to indicate the approximate level of detail that should be
provided in the management plan that is incorporated into the 208 plan.
Alternate LIB . Alternate IIB would be quite similar to Alternate hA
except that the Board that governs the AWA would be elected directly by the
people.
Alternate hIC . Under Alternate IIC, the City of Des Moines would be
designated as the areawide waste treatment management agency. A utility
board would be established as the organizational vehicle. The utilities board
would be established by amending Section 388 of the Iowa Code. Establish-
ment of such a board would also require approval by the voters at a city
election. The board could then proceed to carry out the same basic functions
as those provided under Alternate Plans hA and hIB.
Alternate hID . Alternate hID would organize the AWA as a metropolitan
sewer district under the requirements of Chapter 358 of the Iowa Code. This
requires a petition of 25 percent of the voters in each of the three counties as
well as a favorable referendum of the voters of the entire area. Once
established the sewer district would take over the ownership and management
-------
111—28
of all of the wastewater collection and treatment facilities within the 208
area, ICA and outlying communities.
Obviously there can be many variations and many changes in the details
of the various management alternative and these details may determine the
effectiveness of the management plan.
-------
lv- ’
CHAPTER IV - DESCRIPTION OP PROPOSED PLAN
General Description
The proposed areawide plan includes the construction of one new
areawide WWTP, segregation of combined sewers, flow separators for
combined sewer overflows and strategic storm sewer discharges, promotion of
eropland runoff control options, passage and enforcement of ordinances for
the control of erosion and sediment from construction sites, and reduction in
the urban development of unincorporated areas.
The plan calls for an expansion of the existing Des Moines WWTP
service area. Flows from Camp Dodge, Lovington, Urbandale - Beaver Creek,
Johnston, Saylor Township and West Ankeny would be transported along the
west bank of the Des Moines River. Flows from East Ankeny, Altoona,
Bondurant, Delaware Township, and Pleasant Hill would be conveyed by
gravity along Four Mile Creek. Flows from West Bloomfield, Lakewood,
Highland Hills, Greenfield, Areas B and C, and Bloomfiéld would be
transported to the areawide WWTP by two lift stations, force mains, and
gravity sewers. The existing Des Moines WWTP would be abandoned and the
new areawide treatment facility would be constructed immediately east of
the present site. The year 2000 service population is estimated to be
approximately 360,000 and the peak hydarulic flow through capacity would be
165 MGD.
The sanitary flow from the northwest Des Moines area. Camp Dodge,
Lovington, Urbandale - Beaver Creek, Johnston, Saylor Township and West
Ankeny would be segregated by routing the flow through a new interceptor
sewer which is to be constructed parallel 10 the Westside Interceptor. The
Westside Interceptor presently receives flow from combined sewers. Flow
-------
IV-2
from the combined system would enter the main outfall to the plant up to a
point where the dilution ratio of the combined flow system is 5 to 1. Flows in
excess of 5 to 1 would be diverted to the combined sewer overflows. Flow
separators would be constructed at 11 combined sewer overflows and at three
storm sewer discharges for the removal of significant fractions of the grit,
settleable solids, and floatable solids from the discharges. In this way, these
selected combined sewer overflows and storm sewer discharges would receive
some physical treatment before entering the receiving streams.
Non-point source controls contained within this plan would be achieved
through increasing the subsidy program for cost sharing on cropland runoff
controls, through the passage and enforcement of ordinances for the control
of erosion and sediment from construction sites, and through a reduction in
the rate of urban development of unincorporated areas. A cropland runoff
control subsidy program would provide cost sharing in addition to that
provided under existing programs in order to enable the construction of all
needed terraces and grade stabilization structures by the year 2000.
Construction site erosion and sediment control ordinances, if properly
enforced, would reduce the non-point source sediment loads to streams.
Reductions in the development of unincorporated areas would reduce
potential problems associated with septic tanks or long distance sewer
extensions, solid waste disposal, etc.
Description of Areawide Sub-systems
Interceptors
Plate V-i shows the proposed interceptor network in relationship to the
intensity development pattern for the year 2000 and the sites for the
equalization basins and lift stations proposed on the interceptor network. The
equalization basins vary in size from 0.22 to 7.72 million gallons and serve to
equalize extraneous flows from infiltration/inflow sources. Thus, use of the
-------
IV•- 3
existing interceptor sewers would be optomized. The capacity of each reach
of interceptor is shown on the attached plate together with the size of
interceptor proposed. A detailed description showing the plan and profile
sheets and the exact site proposed for the equalization basins are included in
the Appendix of the Phase Ill report.
Treatment Plant
The proposed wastewater treatment plant would have an average design
flow capacity of 50.83 MGD with a peak flow capacity of 165 MCD. The
proposed plant incorporates grease recovery and grit recovery facilities
followed by conventional primary clarification tanks. Following primary
sedimentation, the flow would be pumped across a synthetic trickling filter
media tower and for BOD reduction and then through an aeration tank for the
purpose of further BOD reduction and partial nitrification. Following the
tower and the aeration facilities, final sedimentation tanks would be provided
together with post—chlorination.
A recirculation system is incorporated into the biological stage of the
treatment process. The sludge generated from the plant would be
anaerobically digested and the digested sludge conveyed by truck to
agricultural land. As a back-up system, landfilling the sludge can be
accomplished also.
The proposed design, construction and plant start-up would occur over a
five-year period and be staged in such a manner that portions of the plant
could be utilized as soon as constructed. The carrying capacity of the present
interceptor system exceeds the design capacity of the proposed plant;
however, segregating combined sewers will substantially reduce flows to the
treatment plant. By providing a process which can be split treated, the plant
can be operated to obtain the degree of treatment necessary.
-------
IV-4
The effluent standards would be as follows: The plant would be
designed for the anticipated flows for the year 2000. Present dry weather
flows are estimated to be approximately 80 percent of that total. All of the
peak capacity would be utilized once the proposed interceptor sewers are
made available.
During normal operations in dry weather, the plant could nitrify the
total flow if necessary. Increased plant efficiency from the standpoint of
effluent quality could be realized by the addition of coagulating chemicals for
additional suspended solids removal in both the primary clarification phase
and in the final clarification phase.
The plant would be controlled by a mini computer in order to
optomize power costs and treatment efficiency. By the time the new plant is
constructed, approximately four million gallons per day of industrial waste
would be treated. The strength of the industrial waste is expected to
decrease as time continues. The population served initially by the plant is
estimated to be 250,000 and the ultimate population served is estimated to be
approximately 360,000. A sketch of the process proposed is included,
together with the proposed plant layout.
Sludge Disposal
The grit recovered from the system would be washed and hauled to the
landfill. The grease collected would either be landfilled or burned in an
incinerator. Primary sludge from the primary clarification tanks would be
pumped directly to anaerobic digesters which are enclosed tanks. The
biological sludge generated from the process would be thickened first by
gravity thickeners (with or without chemical). The thickened biological
sludge would then be combined with the primary sludge in the anaerobic
digesters for a period of several days. Following digestion, the sludge would
be dewatered utilizing chemical conditioning and vacuum filters. The
-------
IV-5
dewatered sludge would then be trucked and spread on agricultural land in
accordance with acceptable standards and in accordance with the rates
determined for the crop and conditions of the land. As an alternate the
digester sludge could be hauled in tank trucks and spread in liquid form on
agricultural land by the use of “big-wheel” type hauling equipment. As a
backup system the dewatered sludge could be hauled to landfill for ultimate
disposal.
Other sludge disposal options considered were incineration and produc-
tion of soil conditioners. The limiting factors affecting incineration are the
rising cost of fuels necessary for effective incineration, the questionable use
of increasingly scarce fuels for sludge disposal and the negative air quality
impact and/or high cost of emission controls to minimize air pollution.
The production of soil conditioners generally requires some form of
composting of sludge with organic matter such as wood chips, sawdust, leaves
or organic garbage. The recommended plan for sludge disposal does not
include this option because information on production costs and marketing of
the product were not available. However, the selected plan would not
preclude future development of the option should the economic indicators be
favorable.
Sludge is not a problem in outlying communities where wastewater is
treated in lagoons.
Management Plan
The management plan would be developed in two stages: an Interim
Plan, and a Final Plan described in more detail as follows:
Interim Management Plan
The interim management plan would take effect April 25, 1977, the
date of the expiration of the present 208 planning program.
-------
IV-6
There would be a new “Areawide Wastewater Agency” created by
amending the “Sewer Planning Agreement” entered into in 1973 between the
Central Iowa Regional Association of Local Governments (CIRALG) and the
26 units of local governments in the 208 area. The new AWA would be
governed and operations under it conducted by basically the same arrange-
ment of committees used in the preparation of the 208 plan, i.e. -
Policy Committee
Technical Committee
with provisions for others, including Coordinating, Citizens and Financial
Committees.
No change would be made in the method of selecting committees, in the
committees t responsibilities or in the method of financing the operation.
The interim management plan would have a life of approximately two
years, being discontinued upon the creation of the ultimate management
system as described subsequently.
The interim AWA would have the responsibility for and it would be its
duty to carry out the following activities.
Program of the Interim Agency
1. Annual Update of 208 plan would be a major responsibility. For the
first year this should include data from the extensive sewer system evaluation
surveys and additional water quality monitoring particularly of the impact of
the combined sewers (as a precedent to reconsidering priorities for the flow
separator program). The Land Use Intensity Plan should be reviewed and
brought up-to-date.
-------
IV- 7
2. Setting of Annual Priorities for Construction . Initial schedules of
improvements have been made for a five-year and a 20-year period. These
would be ipdated annually based on construction completed and new
improvements required.
3. Water Quality Monitoring on an areawide basis should be pro-
grammed in coordination with the local and DEQ monitoring programs.
Additional monitoring needed would have to be financed.
4. Assistance in Preparation of Grant Applications by the local
governmental units would be provided by AWA. Standard “back up” data and
material for such applications would be developed.
5. Coordination with Iowa DEQ would include:
A. Measurement of the relation between the water quality monitoring
and the water quality standards.
B. Review of water quality monitoring to establish compliance with
effluent standards. Recommended actions by local governments in
relation to violations of these standards.
C. Assistance to local governments in complying with NPDES permits.
D. Any review of sewer construction permits as requested by DEQ to
determine conformity with the 208 plan.
6. General Coordination for Control of Non-Point Pollution Sources
would provide for the AWA to undertake such of the following activities as
would be possible under staff and budgetary limitations:
A. Where a watershed was in more than one local governmental
jurisdiction, any of the local governments could request the AWA
-------
IV-8
to provide any coordination needed either in relation to improve-
ments proposed or to improvement of water quality.
B. A special committee could be established to work with the three
counties, the Iowa Department of Soil Conservation and the County
Soil Conservation Districts in the coordination of these programs
with the 208 program for the reduction in non-point agricultural
pollution.
C. AWA would encourage and assist local governments to enact and
enforce comprehensive programs to minimize non-point urban
pollution, such as:
(1) Storm drainage standards for new developments such as
retention basins, manhole diversions, screen separators, etc,
(2) storm drainage channels,
(3) land subdivision control,
(4) street surfacing and cleaning,
(5) snow and ice removal,
(6) erosion control during construction of public and private
project,
(7) littering regulations, and
(8) floodplain and floodway regulations.
-------
IV-9
D. Local governments would inform AWA of major new developments
and changes in zoning and development regulations. Any major
departures from the Land Use Intensity Plan would be made after
consultation with AWA to determine the effect of such changes on
the other parts of the 208 plan.
7. Preparation of Final Management System . A major responsibility of
the interim AWA is the consideration of remaining options and the
determination of the final management system in accordance with guidelines
provided in the following section.
Funding and Staffing of Interim Agency
Activities of the interim agency will require a staff possibly provided by
CIRALG as is done for the 208 program. This staff would be the core of the
much larger staff of the permanent agency. Actual staff and funding
requirements are to be determined.
Final Management Plan
The proposed inter-governmental agreement for an interim Areawide
Wastewater Agency (AWA) provides for the study and analysis of a final or
more permanent AWA. This could be accomplished by:
1. Use of Chapters 28E and 28F of the Iowa Statutes, possibly with
some amendments.
2. Passage of complete new legislation that would apply only to the
Des Moines 208 area.
3. Use of Chapter 358 which enables formation of sewer districts with
some amendments. The entire 208 area would be organized as a
sewer district under this approach.
-------
Iv—1 0
Basic Objectives . The basic objectives of the Final Management Plan
are to:
1. Enable compliance with EPA requirements for 208 Programs.
2. Enable establishment of a permanent water quality management
system on an areawide basis. With a few exceptions such as in the
case of the three counties, the individual local governments have
the power needed to meet water quality management requirements.
These are available for each unit of government individually, but
there is no method or system to bring these together, to combine
them into a coordinated areawide system.
3. Establish a viable areawide wastewater treatment agency with
sufficient power and finances to enable it to apply the resources of
the entire area to the areawide wastewater quality problems.
Investigations made as a part of the 208 Program have indicated
that a fragmented approach will not provide the needed improve-
ment in water quality because significant parts of the 208 area
cannot economically afford to install the facilities and improve-
ments needed to enable them to reach a minimum standard of
water quality. However, the resources of the entire 208 area
(particularly when supplemented with state and federal grants) are
sufficient to produce a solution to the wastewater problems, if
these are approached on an area—wide basis.(1)
The Area-Wide Wastewater Agency (AWA ) would have the following
characteristics:
A well managed area-wide agency would have more influence on state
and federal assistance policies and would be able to help the smaller
local governmental agencies in obtaining such assistance which involves
understanding of complex and ever-changing regulations and guidelines.
-------
‘v-li
1. The name of the agency would include ttDes Moines, Iowa” in order
to identify the locality particularly for prospective bond buyers and
thereby to take advantage of the excellent financial reputation
associated with the name.
2. The area of jurisdiction of the AWA would be the 208 area as
presently constituted. However, there would be provisions enabling
the area of jurisdiction to be extended by annexation or for
reduction in the area to take place after the AWA has been
established.
3. The membership of the AWA should be the local governments
within the 208 area, i.e., the 23 cities and three counties. This
would enable the final management system to evo1veu out of the
interim system. By the present or a different representation
system, the members could elect a smaller Board of Directors to
manage the AWA affairs. If the option to use Chapter 358 is
chosen, the Board would be elected and the local governments
bypassed in the choice of the Board.
The final AWA would have four basic types of functions . These would
be: (1) construction and operation of facilities, (2) planning and monitoring,
(3) coordination, and (4) stand-by functions. These may be described in more
detail as follows:
1. Facilities Construction and Operation
-------
IV—12
a. For the ICA,(2) the AWA would own and operate all wastewater
treatment facilities as well as the trunk sewers. The trunk sewers
would include all sanitary sewers as defined, 3 ) force mains and
pumping stations. The trunk system would also include the
combined trunk sewers within the City of Des Moines. All AWA
operations would be in accordance with State regulations.
b. The outlying communities could own and operate their own systems
or the AWA could operate and finance these upon petition of and
agreement with the outlying community and upon entering into a
separate contract.
c. New trunk sewers and facilities would be financed and built by
AWA. If AWA finances do not allow construction of a facility
municipal or developer financing could be used. Provided that
AWA standards observed acquisition of the facility by AWA by gift
or otherwise could occur subsequently.
2. Planning and Monitoring
AWA would have four planning and monitoring functions as follows:
(2) The ICA is the area served by the proposed year 2000 trunk system that
leads to the central treatment plant on the Des Moines River south and
east of the City of Des Moines. Several major new trunk sewers will
have to be built to serve this area and this construction would require
some time. The boundary of the ICA could change as the area served by
the central system changes. This, however, would introduce such
difficult administrative problems and serious financing uncertainties as
to make this impractical and to be avoided. When the AWA is
established the Board should determine the ICA boundaries in accordance
with the 208 Plan. The AWA should then assume responsibility for all
trunk sewers and all wastewater treatment in the year-2000 ICA and
impose its user charges uniformly over this area. If, in the future, a
greater area is served, the Board could increase the ICA. There would be
no decreases in this area as decreases would impair AWA financing.
See Phase I Report, Plate IV-3.
-------
IV-13
a. Each year the Board would bring the 208 program up-to-date and
transmit same to the governor’s office. This could be done by a
staff within the AWA or by a contract. Public hearings and other
public participation would be a part of this process.
b. Each year, the AWA Board would establish priorities for construc-
tion of wastewater treatment facilities and collection systems (as
well as for other proposals of the 208 program) for all areas and
communities within the 208 area. These would be established by
the Board and would be transmitted to the Iowa DEQ and the U.S.
EPA. Priorities would be established as a part of the AWA
budgetary process. There would be public hearings and local input
into the priority establishment system. This procedure would be an
important part of the AWA capital improvement program.
c. The Board may monitor and test water quality in the 208 area. The
AWA could maintain its own laboratory for water quality testing
purposes. This would be coordinated with the Iowa DEQ to avoid
any duplication.
d. The AWA would monitor all industrial discharges and levy and
collect all industrial cost-recovery charges (meeting EPA require-
ments) as well as monitor discharges to determine applicable
pretreatment requirements.
3. Coordination Functions
AWA would coordinate activities of Federal, State and local agencies in
the attack on water quality problems. This would include the following:
a. Urban Stormwater Program . To comply with the EPA 208
requirement that there be an urban storm run-off program, the
-------
IV- 14
AWA would suggest and/or develop storm drainage management
system where a watershed was in more than one local governmental
jurisdiction. Storm drainage improvements proposed under such
systems with the approval of affected jurisdictions would be
constructed, financed and maintained by the local governmental
units affected, utilizing existing governmental powers. The local
government jurisdictions affected could contract with the AWA to
provide service in connection with these programs. The AWA
would be eligible to receive state and federal grants for these
storm drainage programs and to act as the agent of the local
governmental jurisdiction in dealing with them.
b. Non—Point Agricultural Pollution , a major source of difficulty in
connection with water quality within the 208 area, would be dealt
with by the AWA by the establishment of a special committee to
work with the Iowa Department of Soil Conservation and the
County Soil Conservation Districts to coordinate activities of these
agencies with the 208 program and to assist them in obtaining a
higher level of public funding.
c. Coordination with Iowa DEQ would include:
(1) Water quality standards established by DEQ could be moni-
tored by AWA or the DEQ with monitoring results obtained by
DEQ provided to the AWA.
(2) Effluent standards established by DEQ could be monitored by
AWA with AWA reporting on compliance with standards to
DEQ, or this procedure could be reversed. AWA would
undertake daily monitoring of the wastewater treatment
facilities under its control but would do surveillance moni-
toring only for those not under its control.
-------
IV—l 5
(3) NPDES permits issued by DEQ could be monitored by AWA.
AWA could monitor NPDES permits in outlying areas by
request. AWA would assist local governments in complying
with permit terms.
(4) Sewer construction permits now issued by DEQ for any
construction serving two or more users should be first
reviewed by AWA in order that the lateral and collection
systems be coordinated with the trunk and treatment systems.
Consideration should be given to DEQ delegating this entire
approval system to AWA.
(5) Solid waste disposal, mining and quarrying and feed lot
regulations would remain the responsibility of DEQ with AWA
undertaking an occasional water quality monitoring activity.
d. Joint activities would be necessary between the AWA and the local
governments. These are specified in the subsequent section of the
plan.
e. Voluntary joint activities to improve water quality would be carried
on by AWA with the local governments. These would include:
(1) Conservancy Districts and County Soil Conservation Districts
would be assisted by the AWA agricultural committee. AWA
would monitor agriculturally-related pollution and soil loss
limits. Trends in agricultural practices insofar as their effects
on water quality would be reviewed and AWA would develop a
program of assistance (including financial) for further im-
provement of these practices.
(2) County Boards of Health responsibilities for control of septic
tanks and other individual or small treatment systems would
-------
IV—16
not be changed. However, AWA would assist by monitoring
and investigating areas where septic tank and other such
systems are causing problems and would assist county govern-
ments in reaching solutions to them.
(3) County governments do not have authority to build lateral
collection systems and assess the cost against the area served,
although this might be included in county home rule legislation
now being considered. There are a number of developed
unincorporated areas where this needs to be done. AWA would
assist in obtaining the necessary legislation and would work
with county governments in financing and building the collec-
tion systems.
(4) City and County Governments would be encouraged to enact
and enforce comprehensive programs designed to minimize
non-point urban pollution. AWA would suggest minimum
standards and encourage enforcement of, or programs in
connection with:
(a) Storm drainage standards for new developments such as
retention basins, manhole diversions, screen separators,
etc.
(b) Storm drainage channels
(c) Land subdivision control
(d) Street surfacing and cleaning
(e) Snow and ice removal
(f) Erosion control during construction of public and private
project
(g) Littering regulations
(h) Floodplain and floodway regulations
-------
IV—17
4. Standby Authority
The AWA would have standby authority to contract with local
governmental units for the provision of entire sanitary sewer systems,
including collectors and laterals, to provide storm sewer trunk and lateral
systems and to provide complete wastewater service. There should also be a
standby authority for the AWA to provide water supply and distribution
services by contract. These can all be done under Chapters 28E and 28F of
the Iowa Statues. It would be essential for AWA to maintain a good cost
accounting system for this and for other purposes.
Local Government Obligations . Sanitary sewer collection and treat-
ment services would be provided by AWA with all of the units of local
government in the ICA and with any of those of the 13 outlying communities
that desire to use the AWA services. In consultation with local governments,
AWA would develop minimum standards and each local government in the ICA
would:
1. Require sanitary sewer connection permits and enact and enforce
plumbing and building regulations including those that prevent
foundation and roof drains from being hooked up with the sanitary
sewer system. Fees for these permits would belong to the local
governments;
2. Enforce minimum standards regulating characteristics of materials
discharged into sanitary sewers;
3. Inform the AWA of major new developments and changes in zoning
and development regulations. Further, the local governments
would agree not to undertake major departures from the Land Use
Intensity Development Pattern without consultation with AWA to
determine the effect of such changes on the sanitary trunks or
-------
IV—18
treatment facilities. If such changes would necessitate a replace-
ment, enlargement or duplication of sanitary sewer trunks of
treatment facilities, AWA would determine the needed improve-
ments as well as their costs. After a public hearing, the AWA
would determine whether or not it should undertake such improve-
ments. If the AWA determines that such improvements should not
be made, the local unit of government would have the option of
making and financing the improvements; and
4. Develop, adopt and finance programs for the reduction of infiltra-
tion and inflow in the sanitary sewer system; enact ordinances, or
changes in ordinances, necessary to reduce excessive amounts of
infiltration/inflow.
AWA would have the authority to establish enforcement measures for
municipal obligations in the ICA. Contracts between AWA and outlying
communities would include agreements covering such obligations.
Ownership . The AWA would assume ownership of trunk sewers and
treatment facilities within the ICA and those outlying communities desiring
to use AWA services. Trunk and treatment facilities would be purchased by
AWA through an assumption by AWA of the debt that has been occasioned by
construction of the trunk and treatment facilities by paying to the local
government each year a sum equal to retirement and interest payments for
that year. Reserve funds accumulated to retire such debt would be used to
postpone AWA payments until the reserve funds are exhausted.
Existing sewer districts in the 208 area should be eliminated as a part of
the management plan. Legislation establishing the AWA could provide for
Consideration should be given to other means of compensation as
considered by the management committee.
-------
IV- 19
this with the AWA assuming responsibility for debt payments and the cities
taking over the lateral and collector sewers. A special legal analysis will
need to be made of the best method to accomplish this and this method would
differ if the 208 area is organized as a sewer district.
AWA should have the authority to assume the operation and mainte-
nance of a trunk sewer and to postpone assuming ownership until the trunk
sewer has been placed in a satisfactory condition, until any law suits based on
its adequacy or condition have been settled, or until an agreement concerning
AWA liability has been negotiated with the local government.
Financing . It is important that the AWA have as flexible a financing
system as possible so that it can pay its costs in the most reasonable way
possible. The following are more important elements of the financing system:
1. Costs of planning, monitoring and coordination as previously
defined would be paid for by a real estate tax levied against the
entire 208 area.
2. Construction and operation and maintenance of the wastewater
trunk collection and the wastewater treatment facilities within the
ICA and within any outlying communities desiring to use AWA
services would be financed by a user charge. The user charge
would be based on the amount of water used by each individual user
and would conform with EPA requirements. The user charges
would be uniform throughout all areas served by the AWA. (Some
exceptions might be made or a differential rate used where a larger
water user pre-treats sufficiently.) Standard EPA regulations for
The alternative is to charge these costs against the local governments on
the same basis as the voting. The difficulty with an assessment scheme
is that only parts of the three counties are in the 208 area and the
counties would not be able to pay an assessment without charging persons
who do not live in the 208 area.
-------
IV—20
user charges and for industrial cost recovery would be used when
federal grants were a part of the financing. User charges would be
established each year by the Board as a part of the budgetary
process. Existing intergovernmental sewer contracts would be
cancelled at the time that the AWA goes into operation.
3. AWA would have the power to apply for, receive and spend federal
grants either directly or on a “pass through” procedure.
4. The AWA would be able to issue short-term income anticipation
notes to finance its operations pending collection of user charges.
5. The AWA by action of its Board could issue revenue bonds for
capital improvements based on the user charges. To make the
revenue bonds saleable, revenues would have to cover operation and
maintenance facilities, other fixed obligations and costs and bond
interest and amortization, with a coverage factor of probably 1.2
to 1.5. Thus, if revenue bonds are issued, it would be necessary to
have the user charges higher than the actual money required for
bond amortization and interest, purchase payments, and for
operation and maintenance of the system.
6. AWA would have the authority to issue general obligation bonds
backed up by the ability of the AWA to impose a real-estate tax to
amortize and pay interest on the bonds. AWA would not have to
impose the real estate tax; it would just be necessary for it to have
the authority to do so. The bonds could be amortized by the user
charges. However, with the ability to impose the real estate tax, it
would not be necessary to have such an extensive bond coverage as
would be the case with revenue bonds. Furthermore, considerable
sums of money could be saved as the general obligation bonds could
be issued at a lower interest rate.
-------
IV-2 1
Staffing and Budget . When in full operation, the permanent AWA as
described above would have a total staff of about 125 to 150 persons and a
total budget of $3,000,000 per year, about ten percent uf which ($300,000)
would represent administrative, coordination and planning expense. The
administrative and planning costs of the final agency would be about twice
those of the interim agency.
Time Table . A time table must be agreed upon prior to design and/or
construction of any wastewater facilities that serve more than one political
jurisdiction. A possible time table for putting the management plan into
effect would be:
1. Interim management plan April, 1977 —
and interim AWA April, 1979
2. Enact new AWA legislation by March, 1979 (+)
3. Elect first AWA Board April, 1979
4. Interim financing for AWA, April, 1979 to
filling of key staff positions, June 30, 1980
establishment of first AWA
budget, rate charges, acquisi-
tion of trunks and treatment
plants, transfer of employee
arrangements, etc.
5. AWA first year of full June 30, 1980 to
operation June 30, 1981
-------
v—I
CHAPTER V -
ENVIRONMEN’I’AL FFECTS OF THE PROPOSED PLAN
General Approach to Assessment of Environmental Effects
Environmental input was provided at many steps in the planning process.
In particular, these were: (1) an inventory and analysis of existing physical,
biological, social and economic conditions in the study area (Work Elements
30 and 32); (2) an investigation of land use and water quality relationships as
they affect planning in the study area (Work Element 34); (3) development of
a baseline projection of relevant environmental, social and economic factors
(Work Element 52); (4) screening of subplans with respect to environmental
effects (Work Element 59); (5) the establishment of significant environmental
restraints relating to water quality (Work Element 61); and (6) the screening
of areawide plans with respect to environmental effects (Work Element 70).
This report is the final step - an overview of the environmental impact of the
preferred plan.
Steps 4 and 6 also provided opportunity for resident professional
personnel and private citizens in the study area to examine environmental
information and its use in relation to the overall planning effort.
Impacts on Water
The proposed areawide plan is a combination of subplans for the
reduction and control of point, intermittent-point and non-point sources of
pollution. Alternative subplans were developed in each area on the basis of
existing water quality data and on water quality projections made with the
Storm Water Management Model (SWMM).
-------
V-2
The existing water quality and quantity data, summarized in Chapter II
of this report, serve three important functions in assessing the environmental
impact of the proposed plan. They give a general overview of the existing
water quality and quantity in the 208 study area; they identify areas where
water quality and quantity problems exist and thereby assist in locating
specific sources of pollution; and they use existing water quality data for
calibration of the stormwater management model. Calibration is an essential
step in the development of a valid model capable of predicting water quality
under varying conditions of stream flow, temperature and waste input.
Calibration requires a data base compiled for a particular stream condition or
event. The state of the art in receiving water modeling allowed for the
adjustment of modeling parameters in order to simulate actual stream quality
within reasonable accuracy.
Model calibration for the 208 study entailed fitting the computer model
to known and estimated low-flow quality and quantity information and
adjusting the model coefficients (i.e., reaeration decay, roughness, etc.) that
has not been specified by known or measured values.
After model calibration dry and wet weather conditions were modeled
under present and future conditions. Projecting water quality conditions is
useful in developing options for the control of pollution sources — it allows for
the evaluation of future land use plans, crop management plans and point-
source management plans, with regard to their effect on water quality and
quantity in the study area. Various control options and subplans were
modeled for non-point and intermittent point sources of pollution. Reduc-
tions in mass loadings of pollution with respect to existing conditions were
generated for point-source control options and subplans, and resulting water
quality conditions in the receiving streams were simulated.
The proposed plan would reduce wasteloads (BOD, suspended solids and
ammonia nitrogen) discharged to receiving streams by approximately 60
-------
V- 3
percent due to the point source control strategy. Intermittent source
wasteloads (including fecal coliform bacteria) would be reduced by approx-
imately 30 to 50 percent. Non-point source wasteloads would be reduced by
approximately 60 to 70 percent.
While the point-source control portion of the proposed area wide plan
would have little effect on water quantity in the study area, it would have a
major impact on surface water quality .
Under both 1975 conditions and dry weather conditions, streams such as
Fourmile Creek, Camp Creek, and North River exhibit D.O. concentrations
below 4.0 mg/i, ammonia-nitrogen levels in excess of 2.0 mg/i, and fecal
coliform counts in excess of 18,000 MPN/100 ml. Although standards are not
violated in these general classification streams under dry weather conditions,
the water quality in these streams under 10-year, 7-day low flow is poor. The
water quality in the Raccoon River is very good under these conditions
because no wastewater is discharged to it in the 208 study area. Beaver
Creek, however, exhibits a multitude of water quality violations during 10-
year, 7-day low flow conditions. Dissolved oxygen levels lower than 3.0 mg/i,
ammonia-nitrogen concentrations in excess of 3.0 mg/i, and fecal coliform
counts totaling more than 60,000 MPN/100 ml occur. These water quality
violations appear to be due to the wastewater discharges from the Grimes and
Urbandale treatment plants.
The middle Des Moines River (from Saylorville Dam to the Raccoon
River) exhibits very good water quality due primarily to the insignificant
pollutant loading it receives either directly or from its various tributaries.
However, the lower Des Moines River (Raccoon River to Red Rock Reservoir)
does exhibit dissolved oxygen and feeal coliform violations during low-flow
conditions. The dissolved oxygen concentration reaches a minimum of
approximately 4.2 mg/i about ten miles below the Des Moines main plant. In
addition fecal coliform counts approach 80,000 MPN/i00 ml in the Des
-------
v-4
Moines River immediately downstream of the Des Moines main plant.
Although it is apparent that these violations during low flow conditions are
caused by the discharge from the Des Moines Main plant is should be noted
that the Des Moines River recovers to meet stream standards about 20 miles
below the plant outfall.
In summary, violations of the statets water quality standards under 10-
year 7-day low-flow conditions occur on Beaver Creek due to discharges from
the Grimes and Urbandale plants, and on the Des Moines River due to the
discharge from the Des Moines main plant.
Under the proposed plan, many outlying wastewater treatment plants
will be eliminated. Water quality in Beaver Creek would improve substantial-
ly. Winter D.O. levels and summer and winter ammonia-nitrogen concentra-
tions would be well above state standards. D.O. concentrations during the
summer months at Q107 may drop slightly below average standards in Beaver
Creek due to the Grimes discharge, but overall improvement in water quality
will be significant.
In the Des Moines River, under low flow conditions, water qualtiy
improves greatly under the proposed plan. Dissolved oxygen, ammonia-
nitrogen, and fecal coliform levels all fall within water quality standards.
Under wet weather conditions, both water quality and water quantity
(to a lesser extent) would be affected by the implementation of the proposed
plan. During Phase I of the 208 planning process, the 1 year - 24 hour, 5 year
- 24 hour, and 10 year - 24 hour storm events were modeled. Results of this
modeling effort appear in the Phase I report. The effect on area receiving
streams varied greatly. An evaluation of the pollutional impact of wet
weather on Beaver Creek begins with an inspection of dissolved oxygen
concentrations. Average dissolved oxygen values for the 1-year, 5-year and
10-year 24-hour storms were similar with values above 5.0 mg/I at all
-------
V-S
locations except one. At Beaver Creek river mile 16.8 average dissolved
oxygen levels were determined to be approximately 3.0 mg/i with the 10-year
storm having the highest value of 3.72 mg/i and the 5-year storm having the
lowest dissolved oxygen level of 2.93 mg/i. These values would appear to be
below the Iowa Department of Environmental Quality’s required daily
minimum for dissolved oxygen of 5.0 mg/i.
Average fecal coliform concentrations in Beaver Creek for the modeled
storms generally increased toward the creek mouth. While values for all
three storm events were of the same order of magnitude, concentrations
occurring during the 10-year storm were consistently the highest. Maximum
values in Beaver Creek were over 40,000 MPN/lOOml.
Dissolved oxygen concentrations for Walnut Creek indicate concentra-
tions above the State’s standards at all locations for the three modeled storm
events except at the creek mouth during the 1-year storm. The dissolved
oxygen value at this point was 1.81 mg/i during the 1 year storm. Dissolved
oxygen concentrations for the S-year and 10-year storms at the mouth of
Walnut Creek approached 8.0 mg/i. Fecal coliform concentrations in Walnut
Creek were consistently higher during the 10-year storm event than during
the other storm events modeled, with a maximum of about 70,000 MPN/iOO
ml.
An evaluation of the pollutional impact of the three modeled wet
weather conditions on the Des Moines River involved not only runoff, dry
weather point source dischargers, and wet weather point source dischargers,
but also other sources of pollutional loading to the river. These other sources
include the flows and loads from Beaver Creek, Walnut Creek, and Raccoon
River and both storm and combined sewer overflow loadings from the City of
Des Moines and other sewered areas. During wet weather modeling, the
dissolved oxygen limits fell below minimum State standards from river mile
204 to 206 (the two-mile reach below the confluence of Beaver Creek and the
-------
V-6
Des Moines River). Ammonia nitrogen concentrations exceeded 2.0 mg/i
from river mile 198 to 206 (the eight-mile reach between the confluence of
Beaver Creek and the Des Moines River and Highway 69 bridge). Also, fecal
coliform concentrations above 2,000 MPN/100 ml were evident from river
mile 190 to i96 (the six-mile reach below the Des Moines Main sewage
treatment plant outfall). Although these levels do not seem extremely
critical when compared with historical river data, a consideration of the
baseline flow rates preceding the 10-year storm in the Lower Des Moines
River (12,000 cfs from Saylorville Dam and 4,000 cfs from Raccoon River)
indicate a considerable mass loading of pollutants and, consequently, a
potential for water quality problems.
Other major sources of water quality and quantity problems have been
evaluated throughout the 208 planning process. Intermittent and non-point
sources such as urban and agricultural runoff, storm and combined sewer
overflows, and various point - non-point sources received engineering
considerations and computer modeling efforts to evaluate their impact on the
study area receiving streams. Results of these investigations are reported in
Work Elements 55, 56, 57, 59, and 70.
Under the intermittent point source control portion of the proposed
areawide plan, separated sewage will be removed from the combined sewer
system, thereby decreasing both flow and waste concentration from the
combined system. Also, flow separators would be installed at selected
combined and storm sewer discharge points. These control options will
greatly reduce pollutional loading to the Des Moines River. This would have a
substantial effect on improving water quality and reducing water quality
violation. It should be noted that the intermittent controls will not reduce
the overall quantity of wastewater generated.
Under the non-point source control portion of the proposed plan,
pollution loadings to all receiving streams will be greatly reduced. This
-------
V-7
control subplan, together with the point source and intermittent point source
control portions of the proposed plan, will eliminate all water quality
violations in major receiving streams in the study area.
Projections (year 2000) made with the SWMM model showed that future
development in the area would increase the quantity of non-point pollution
compared with present quantities and conditions (Table V-7, CIRALG, 1976a).
However, by modifying future development to minimize water quality impact
and by increasing measures to minimize agricultural runoff, projected
pollution was substantially reduced in all parameters.
In summary, the environmental impact of the proposed areawide plan on
water quality and quantity must be viewed with three main considerations.
First, modeling results indicate that the proposed plan will substantially
improve water quality in the study area when compared to existing
conditions. It will eliminate water quality violations which presently exist in
the area t s receiving streams under both critical dry and wet weather
conditions; this is one of the main purposes of the 208 planning process. It
will also tend to reduce the quantity of wastewater generated in the study
area to a limited extent.
Secondly, the proposed plan does not appear excessive in its control
requirements. Although water quality violations indicated by the modeling
and by existing data are eliminated, the plan does not require controls to such
an extent that excessively good water quality results, or that implementation
and operation costs are excessive.
Thirdly, the overall proposed areawide plan is a combination of three
source-specific subplans. In order to obtain the overall objectives of the 208
plan, all pollution sources (point, intermittent, and non-point) must be
addressed and controlled. Although overall implementation of the proposed
areawide plan will obviously be a phased project, the acceptable results with
-------
V-8
regard to improved water quality depend not on one source option control
alone, but implementation of all three source control portions of the plan.
Impacts on Air
There are two air pollutants for which maintenance plans have been
prepared for Polk and Warren Counties: carbon monoxide and suspended
particulates. In the City of Des Moines auto exhaust emissions account for
approximately 90 percent of the carbon monoxide (CIRALG, 1974). Auto
engines themselves emit only a small fraction of suspended particulates, but
they can generate a large amount of fugitive dust depending on roadway and
weather conditions. Urban and non-urban land surfaces in the study area
contain sources of fugitive dust - unpaved roads and parking lots. Industrial
air emissions are under good control in the study area at the present time
(Moss, 1975).
The proposed plan would have no major primary impact on the air
quality of the City of Des Moines or the region. No sludge incineration is
anticipated, and air emissions from the proposed collection and treatment
facilities will be minimal. During construction of both, however, locally
disruptive fugitive dust can be generated depending on weather and soil-water
conditions during excavation.
The proposed plan will have a positive impact on air quality mainte-
nance in the long run through its designation of permanent open space areas
and corridors in the intensity development pattern. These areas will serve as
sinks for a certain fraction of the air pollution in the vicinity and they also
serve to decrease the overall density of air-polluting land uses.
The form of growth anticipated in the area will require continued strong
reliance on the private automobile. This will cause the potential for carbon
monoxide pollution to rise; the potential will be held in check by the success
-------
V-9
of auto manufacturers to design and build low emission engines. The
development of an areawide mass transit plan could aid in controlling air
pollution, but no active planning is currently underway for this option.
Impacts on Land Use
The procedures followed in developing the areawide wastewater
management plan were designed to focus early in the study on the
interrelationships between land use and water quality. Thus an Intensity
Development Pattern (Land Use Plan) was utilized as the base for the future
point, intermittent point and non-point source plans which make up the
areawide plan.
In developing the Intensity Development Pattern (IDP), analyses of land
use relative to water quality, detailed soil capability end environmenta]
analyses were made for the area. In addition, local policies as represented in
each jurisdiction’s comprehensive plan and policies were evaluated. Alterna-
tive IDP’s were formulated and included: (1) Minimum Public Expenditures
Pattern, which was based on limited public expenditures for additional
utilities systems; (2) a Minimum Environmental Effect Pattern, based on land
use decisions to achieve minimum negative environmental effects; and (3)
Composite Pattern, based on present development plans for local govern-
ments adjusted to reflect regional population estimates. The IDP selected,
after public hearing, involved key parts from each. The Composite Plan was
adopted, with adjustments to include selected elements of both the Minimum
Public Expenditures Pattern and the Minimum Environmental Effects Pattern.
Thus, the IDP selected reflected environmental and cost considerations as
well as the political realities of the area.
The IDP was used as a basis for development of the Areawide
Wastewater Plan. Point source flows and run-off and intermittent flows were
developed, wherever possible, from the IDP. Many of the non-point source
areas of concern were an outgrowth of the environmental analysis.
-------
v-I 0
Because of the desirability of providing a regional treatment facility,
the final areawide plan includes serving suburban and satellite communities
such as Ankeny, Altoona and Bondurant through the extension of large trunk
sewer lines through undeveloped agricultural land in unincorporated areas.
(See Plate V-i.) The Management Plan calls for control of development
pressure along these trunk lines (which under the IDP are to remain in
agricultural use) by a coordinated program based on the construction permit
requirement by Iowa DEQ. Approval by DEQ of a permit to construct would
be based in part upon design capacity of the trunk line and the allocation of
wastewater treatment units for a jurisdiction as reflected in the IDP. The
AWA (through CIRALG) would have responsibility for local conformance with
the water quality portions of the IDP and would provide to DEQ the waste
treatment units allocated to each local jurisdiction. The procedure is
somewhat complex, and limiting development will be most difficult to
accomplish. It will require the desire and cooperation of the affected local
jurisdictions. This will be the major impact of the Areawide Wastewater
Management Plan on land use.
A major element of the non-point program could be the restriction of
development in unincorporated areas. This would be accomplished by
requiring very large lots (such as three to five acres) before a permit to use a
septic tank could be granted. This would direct urban growth into those areas
served by the sanitary sewer systems. This should not overload the sewer
systems because their capacities are designed to accommodate projected
growth and to allow reasonable flexibility.
The impact of the Areawide Wastewater Management Plan on existing
development will consist primarily on the disruptions and other problems
associated with new construction through developed areas, as well as the
improvement in value and desirability of land uses for which plan improve-
ments will reduce water quality problems (such as basement back-ups and
septic tank failures). Specific impacts would be:
-------
PLATE V-I
PRELIMINARY INTENSITY
DEVELOPMENT PATTERN
-YEAR 2000—
RESIDENTIAL - LOW DENSITY
(LESS THAN I I .U./ACRE)
E J RESIDENTIAL - MEDIUM DENSITY
(I TO 99 D.U./ACRE)
RESIDENTIAL - HIGH DENSITY
(bR MORE D.UJACRE)
NON-RESIDENTIAL
LOW INTENSITY
NON-RESIDENTIAL
LOW INTENSITY (SPECIAL)
NON-RESIDENTIAL
MEDIUM INTENSITY
NON-RESIDENTIAL
HIGH INTENSITY
I I CROPLAND
I PASTURE, FOREST & VACANT
t PERMANENT OPEN SPACE
_____ WATER
— PROPOSED MAJOR TRUNK LINE
PROPOSED REGIONAL TREATMENT
FACILITY
OTHER TREATMENT FACILITIES
AREA SUBJECT TO DEVELOPMENT
f PRESSURES FROM TRUNK LINE
LOCATION
r1j t’E IN MILESj
CENTRAL IOWA REGIONAL ASSOCIATION
OF LOCAL GOVERNMENTS
K KIRKI-4AM MICHAEL AND ASSOCIATES
I-4ARLAND BARTHOLOMEW AND ASSOCIATES
AMERICAN CONSULTING SERVICES, INC
KIRKHAM TENECH ENVIRONMENTAL CONSULTANTS,
MICHAEL INC • CARLETON D. BEH AND COMPANY
PREPARAT ON OF UIS ETAP WAS FINANCED THROUGH A GRANT FROM ThE
US E ’ POP UINTA( PROTECTION AGENCY - R SECTION 20$ OF T14E
FEGERAL WATER POTLUTION CONTROL ACT AMENDMENTS OF T9T2
-------
v-i 2
1. In the ICA the construction of sewer trunk lines through developed
areas will cause temporary disruption of land uses. In most
instances the trunk lines follow the stream valleys, where minimal
disruption to urban development occurs. However, the ecosystem
would be temporarily impacted in the natural areas.
2. Within the ICA, the interceptor system for segregating the
combined system through the developed areas will disrupt the urban
land uses that are adjacent to it. Where this involves location in a
street it will be particularly disruptive to residents and to street
traffic for a short period of time.
3. Construction of flow separators at points throughout the ICA will
have a disruptive impact during construction. The land area
required for a flow separator is relatively small (less than one
acre). They will be located either in the downtown area or along
trunklines following a stream. Construction in the downtown area
will be temporarily difficult and disruptive. When completed, the
flow separators will be totally underground and the land use can be
resumed,without adverse impact.
4. Within the ICA, the construction and location of equalization basins
may have adverse impacts. An equalization basin could have as
much as 10 to 15 feet of the structure above grade and will be a
sizeable physical structure relative to other uses. In many cases,
these have been located in areas where abandoned lagoons exist and
where they are well separated from adjacent residential uses.
Surrounding land areas could be graded and landscaped to minimize
visual intrusion.
5. The additional sewage capacity provided to the entire ICA by the
point source improvements (including trunk line extensions) will
-------
v-i 3
improve the overall health, desirability, and aesthetics of the urban
area, which now has marginal or less than satisfactory point-source
control.
6. The ability of the regional system to sewer homes presently on
septic tanks in the corridor between Ankeny and the City of Des
Moines would increase the quality and health conditions of that
area for residential development. Other areas which are presently
served by septic tanks and would be picked up in the southern part
of the ICA would be helped as well.
7. In the outlying communities there would be some disruption
associated with construction of new trunks or treatment facilities,
or expansion of existing treatment facilities. At the same time,
the ability of the new facilities to alleviate existing problems
would make each community a more desirable place to live.
8. The enforcement by local government of erosion controls for
construction sites would be particularly helpful to those existing
land uses in the areas where new development will take place.
With new construction required to meet erosion standards, the
property owners will be protected from damage to the storm water
system and sedimentation on their property.
The land use pattern which exists today would not be significantly
altered. Travel patterns and other service patterns such as solid waste
disposal would not change from the present pattern.
Land Use Impact on Anticipated New Development
Future development in the 208 study area would be greatly affected by
the location and timing of the Implementation Areawide Wastewater
-------
v-i 4
Management Plan. The projection of population for the study area calls for a
population growth to 400,000 by the year 2000. The development of the
utility system would help the region to meet the 400,000 population
projection by making the community more attractive to industry and to
residential growth than it has been during this moratorium period. The Des
Moines Area can market itself as a metropolitan area which has come to grips
with the problems of wastewater management. It would have instituted a
management system and the technical plans necessary to provide for its
future. Future industry and other investment will see this as an example of a
farsighted community and location in the Des Moines area will be much more
attractive to it.
Impacts of the plan on new development in the 208 area are listed
below:
1. Within the ICA the extension of trunk lines through undeveloped
agricultural portions of the unincorporated areas can be expected
to be the most critical land use problem resulting from the plan.
Easements would be required from land owners who in turn would
have to be told that they cannot tie on to the trunk line which
extends through their property unless the projected population and
land use is in conformance with the adopted IDP and technical
requirements. The value of the land surrounding this trunk line
would increase and the desire of those owning the land or land
around to subdivide or to develop would increase. Under any
circumstances it would be extremely difficult to keep involved
communities or counties from revising the intensity development
pattern and thus permitting development along the trunk lines. The
three to which this applies are those shown on Plate V-i: (1) the
area between Des Moines and the East Ankeny treatment plant; (2)
the area between Pleasant Hill and Altoona and between Altoona
and Bondurant; and (3) the area from Lakewood subdivision to south
-------
v-I 5
Des Moines, in Warren County. One of the outcomes of this
problem may be the annexation of portions of the unincorporated
area by adjacent cities and evc’ntua) revision of their allocation of
land use.
2. The development of the west trunk from Des Moines to the West
Ankeny plant would open up that corridor for development. This is
in conformance with the IDP and would allow such development to
take place with sewer service.
3. As a result of the development of satellite cities and suburban
cities, some agricultural land which might be kept in production
would be utilized for residential and commercial/industrial de-
velopment.
4. As a result of the expansion of the satellite cities, some additional
travel costs and increased travel patterns between these communi-
ties and the urban center can be expected. Only limited growth is
expected in the outlying communities; upgrading existing facilities
will have only minimal effects on growth of these cities. As in the
usual case, the wastewater sy tcm for smaller localized cities
follows development resulting from other influences.
(The proposed freeway through the eastern and southern sectors of the
central urban area was not included in 208 considerations because completion
was not considered likely prior to the year 2000.)
Biological Impacts
Rare/Endangered Species
The preferred plan has no identifiable, direct impact on the status of
rare/endangered plant or animal species in the study area. Land areas
-------
v-i 6
directly affected by proposed facilities constru tion have already been
disturbed by urban and agricultural land uses to the exteflt that potential
habitats of rare/endangered species are destroyed or irretrievably altered.
In order to protect habitat space in the study area where native plant
and wildlife species (including endangered ones) can persist or thrive,
pcrmane!lt open space must be protected in the vicinity of Saylorville Lake
and Big Creek Reservoir, the old channel of the Skunk River and the Raccoon
River flopdplain area - particularly the D llas Co inty and southeast Polk
County portions. These areas all offer wetland and wooded habitats. The
proposed Intensity Development Pattern, where applicable, proviç es this
protection. The Iowa State Conservation Commission is working for the
protection of addition l prairiç remnant sites, including one site in the
northern part of the study area now privately Qwned.
Wildlife -labitats
Wildlife habitat areas in the study area other than those just mentioned
are the Des Moines and Raccoon I ivers and all their tributaries, Dale Maffit
Reservoir, Brenton Slough (Beaver Creek South of Granger) and the State and
County parks mentioned earlier in this report. Operation of the areawide
treatment plant proposed in the plan along with the proposed control of
combined and storm sewer overflow discharges to the Lower Raccoon River
and Des Moines River between Birdland-Union Park and the present
treatment plant will improve quality to the extent described in the Water
Quality section of this Chapter, beginning approximately two to four years
from now. Improvement in cropland runoff controls proposed in this plan will
also improve water quality in a significant way starting in about five years
fr9m now. These improvements in water quality will gradually improve
conditions fpr fish and other aquatic animal species in the study area.
Perhaps the most sign fican positive impact of water quality on aquatic
animal habitat will come from reduced pollutant loadings on small tributary
-------
v-i 7
streams in outlying areas as a result of agricultural non-point pollution
controls The most important positive impact of the plan on terrestrial
wildlife habitats would be in protecting the floodway corridors along the
Raccoon, Walnut, Beaver, Des Moines, Four Mile, Middle and North Rivers
(Creeks) as called for in the Intensity Development Pattern. (See Plate V—i.)
In each case composites of aquatic, wetland, floodplain forest and gradations
toward upland forest habitats are protected to the long-term benefit of plant
and animal species.
The impact of the plan on eutrophication of waterways in the area and
its resultant impact on aquatic wildlife is not easily predicted. The operation
of Saylorville Dam and Lake will have a profound impact on the ecological
dynamics in the Des Moines River through the study area regardless of the
impact of the proposed 208 plan. Improved control of nutrient-rich runoff
from cropland may help slow eutrophication slightly, but the effect of
residual nutrients in lake and reservoir sediments (particularly phosphorus)
will continue for a long time even if there is a marked decrease in nutrient
inputs.
Crops and Managed Vegetation
The proposed plan recognizes the prime importance of agricultural
productivity to the study area and the Nation. There are approximately
351,000 acres (68 percent of the study area) now used for cropland, and
322,000 acres (63 percent) are projected to remain in cropland by the year
2000. Intensity Development Pattern alternatives calling for a smaller
decrease in cropland were considered socially and economically unfeasible.
Water and soil conservation measures recommended by the plan as non-point
source pollution control measures would contribute to the maintenance of
crop productivity with lower levels of fertilizer supplementation. These
measures are also critically important to the protection of long-term soil
fertility and agricultural potential.
-------
v-i 8
Impact on Environmentally Sensitive Areas
Sources of Potable Water
The lower Raccoon River Valley is protected in the proposed plan by its
designation as permanent open space to the limit of the 100-year floodplain.
The floodplain of two major tributaries, Sugar and Walnut Creeks, are also
designatçd as permanent open space. This designation by the plan is a
minimum requirement for these areas; additional protective measures may be
required in the coming years to minimize the potential hazard brought by
contaminated runoff or contaminated groundwater moving in the watershed
toward the lower Raccoon. A limit on all direct discharges to the Raccoon
River for a five-mile zone extending upstream from the intake galleries
(approximately to 1-35) is also a minimum requirement (Johnson, 1976);
additional limitations may be advisable or required in the future, depending
on water quality received at the treatment plant. An area about which very
little is known but which may represent a potential health hazard is the
quantity, impact and protection against viruses in potable water intake.
It is critically important that all aspects of the water quality
management plan proposed here which directly or indirectly affect the
quality of water in the lower Raccoon River be reviewed carefully and at
regular.intervals in relation to water quality data at the potable water intake
site(s).
Surface Waters
The short-term (approximately five-year) impact of the plan on quality
of surface water would result from controlling polluted discharge from
combined sewer systems discharging to the lower Raccoon (downstream of
the water treatment plant) and to the Des Moines River in the City center of
Des Moines. Longer term improvement (approximately 10-year) can be
-------
V- 19
expected as a result of non-point source control in agricultural land areas.
Lake Red Rock would improve gradually as a result of these combined
positive impacts, but over a longer period of time.
Wetlands
The plan would prevent further degradation of wetlands in the study
area by curbing soil erosion through practices as non-point source controls in
agricultural land and by protecting the floodplain areas designated in Plate II-
4 from development.
Floodplains and Flood Retention Areas
The plan recommends that all 100-year floodplain areas be designated
as permanent open space. The policies for management and use of these
areas are being formulated or will be formulated by individual units of local
government and the Corps of Engineers during the next several years. Any
excavation or construction in the flood retention area of Lake Red Rock
decreases flood retention capacity must be compensated for by the creation
of an equal amount of new flood retention capacity nearby in the flood pool
areas.
Groundwater Recharge Areas
The most significant groundwater recharge areas coincide with the 100-
year floodplain designated in Plate 11-4. The plan recommends retention of
these areas as permanent open space with specific use limitations as
designated by individual units of local government.
Prime Agricultural Lands
The plan calls for the retention of over 90 percent of the present
cropland through the year 2000.
-------
V-2 0
Public Outdoor Recreation Areas
There is potential conflict in several cases between proposed equaliza-
tion basins and existing or proposed outdoor recreation areas. (City of Des
Moines Plan and Zoning Commission, 1976.) In most, if not all, such cases the
conflict could be resolved by basin design and placement which would
minimize or prevent any interference with recreational land uses. In fact,
the basin surface may itself serve as a recreation area, for example, tennis
courts. There would, of course, be initial disruption during basin construc-
tion; periodic maintenance and repair would cause minor interference with
recreational land uses. Odor would be controlled by built-in abatement
systems.
The first area of possible conflict is at the proposed equalization basin
site north of S.W. 80th Street (County Line Road) near the southern extension
of Fleur Drive (Highland Hills). A neighborhood park proposed for this area
would serve residents south of Army Post Road, west of S.W. 9th Street and
north of S.W. 80th Street.
The second area of possible conflict is the proposed equalization basin
site near Prospect Road directly east of Broadlawns Hospital. This is part of
Prospect Park (now a community park - to be reclassified). The exact site
proposed for the basin is now used as a refuse dumping area, therefore, the
net result of placing the basin could be significant and positive for the area as
a whole.
The plan has a positive impact on recreational use of the Des Moines
River and riverfront areas. Improved water quality and increased access will
benefit recreation.
-------
V-2 1
Sensitive Geological Areas
The bedrock beneath the Pleistocene mantle of glacial drift, bess and
river deposits in the study area consists of shale with interbedded limestone,
sandstone and thin coal seams. While there had been extensive coal mining
activity in the Des Moines area earlier in the century, the prospects for
returning to commercial production in this area do not appear very high at
the present. A statewide inventory of coal resources now in progress will
shed more light on this matter (Avcin, 1975).
A potential problem caused by the extensive coal mining activity earlier
this century is that much of south-central Polk County is underlain by
shallow, mined out voids in the upper bedrock layers which represent possible
subsidence areas. The incidence of subsidence to date is low, however, and
the chance of major subsidence appears to be very low.
An underground (bedrock) storage area for liquid petroleum gas is
located east of Pleasant Hill with substantial storage volumes at depths of
375 and 575 feet (Dorheim, 1975).
Date on the distribution of recent earthquakes and the map of seismic
risk zones in the United States indicate that the probability of significant
earthquakes or tremors in the study area is relatively small (Spencer, 1972;
Cargo and Mallory, 1974). There are no known fault zones in the area along
which tremors are particularly likely to develop.
Environmental Impact of Facility Plans in Outlying Areas
Introduction
This section of the report summarizes the environmental impact of
proposed facility plans for each community for which it was found not cost-
-------
V-22
effective to include in an areawide treatment system. The primary reason
for excluding them from an areawide system was the required transport
distance.
Assessing the overall impact of a given facility plan on water quality in
rural areas is made particularly difficult because (1) baseline data on
upstream water quality in small, rural streams is generally not available; (2)
the impact of non-point sources of nutrients, BOD, suspended solids and
bacteria from agricultural land areas is highly variable with rainfall, season
of the year and agricultural management methods; (3) the impact of effluent
from existing treatment lagoons and from septic tank seepage beds also
varies considerably throughout the year - impact is generally not sought or
recognized except in extreme cases where gray, heavily contaminated
seepage is evident at the surface of waterways or saturated soils; and (4) the
efficiency of lagoon treatment systems is reduced during cold weather, when
the organic load is highly variable or when the water level in the lagoon is
poorly controlled.
All proposed plans for outlying communities have certain positive
environmental effects in common. By eliminating septic tanks, undersized
lagoons or poorly functioning mechanical plants, the proposed plans would (1)
improve public health aspects of each community by reducing the chance of
transmitting pathogens from waste systems to water sources and places of
human contact; (2) increase property values by eliminating waste disposal
problems or questionable situations; (3) increase opportunities for additional
housing in the community.
All communities confronting the change from septic tanks to a
collection system face two major problems in common - the high capital cost
and the community disruption caused by installing the pipes.
In all cases where new or expanded lagoons are proposed, the lagoons
would be built at elevations higher than that reached by the 100-year flood
-------
V-2 3
level of rivers and streams and the flood pool elevation of Lake Red Rock in
the case of communities in the southeastern portion of the study area.
Necessary precautions would also be taken to minimize erosion of the inner
and outer walls of the lagoon, that muskrats would be prevented from
burrowing in the lagoon walls, that the lagoon would be enclosed by fencing to
prevent access by young children, and that mosquito populations would be
controlled as needed during summer months.
All loss of flood retention capacity caused by construction in the Lake
Red Rock flood pool area must be compensated by an equal volume of newly
created flood capacity. This flood control requirement will apply in the
facilities proposed for Runnells, Hartford and Carlisle.
Alleman
Proposed Plan: Abandon septic tanks; build collection system and
treatment lagoon.
Impact on Water Resources . Alleman is located near the south edge of
a preglacial channel of the Skunk River. A buried aquifer (extending to over
200 feet below the surface in some locations) now lies along this channel. To
minimize any potential threat to the water quality of the buried aquifer by
contaminated seepage, the lagoon should be located as far south of the village
as practicable. (The proposed site is one-fourth of a mile south of Alleman.)
Effluent from the lagoon would be discharged twice annually to
Fourmile Creek under high stream flow conditions. The lagoon effluent would
be much higher in quality than the present discharge from collected septic
tank outfalls; therefore the overall quality on Fourmile Creek would be
substantial improvement in water quality.
Impact on Air Resources . No significant impact foreseen.
-------
V-2 4
Impact on Land Resources . Approximately seven acres of agricultural
land would be required for the treatment lagoon and supporting land area.
Necessary additions to the existing collection system would cause short-term,
local disruption of land corridors in the town and leading south to the new
lagoon site.
Impact on Biological Resources . The treatment lagoon would drasti-
cally reduce the pollution loadings now discharged to Fourmile Creek and
thereby significantly improve conditions for aquatic animals, including a
beaver colony downstream of the present discharge point.
Impact on Environmentally Sensitive Areas . No significant impact
foreseen.
Impact on Socio-economic and Cultural Resources . There would be a
significantly enhanced sense of security provided by eliminating the polluted
discharge to Fourmile Creek and thereby improving its water quality.
Recreational value of the Creek would be restored.
The cost of making these improvements would be disproportionate to
the available financial resources of the community and private customers
served. Therefore, additional funding sources would be required to implement
the proposed plans.
Impact on Aesthetic Features . There would be occasional odor
generated in the vicinity of the treatment lagoon. Elimination of polluted
discharge to Fourmile Creek would increase the aesthetic value of the Creek.
Carlisle
Proposed Plan: Expand existing lagoon.
-------
V-2 5
Impact on Water Resources . The existing treatment lagoon is in the
flood pool area of Lake Red Rock. It overlies alluvial aquifers of the Des
Moines River, and it discharges to the North River, a tributary of the Des
Moines. Expanding the lagoon would decrease the probability of contamina-
ting one or more of the water resources named, but the probability would not
be eliminated altogether. The most important impact of this plan would be
that wastewater could be retained for longer periods of time during which the
lagoon is operating at reduced efficiency (winter months), thereby greatly
reducing the discharge of poorly treated wastewater. The proposed plan calls
for discharge twice annually (during high flow stream conditions), which
provides the minimum practical impact on the water quality of North River.
pact on Air Resources . No significant impact foreseen.
Impact on Land Resources . An additional 13 acres of flood-prone
farmland would be required in addition to the 35 acres now used for lagoons.
Impact on Biological Resources . Upgrading the lagoon would improve
conditions for aquatic animals in the North River. Discharging treated
effluent only twice yearly under high flow conditions on the receiving stream
would greatly improve habitat quality.
Impact on Environmentally Sensitive Areas . The land surrounding the
present and proposed future lagoons is flood prone by virtue of being in the
flood pool area of Lake Red Rock. This means that under wet weather of
flood conditions, the water table could rise close to or perhaps even above the
level reached by the zone of saturation formed by the lagoon. The potential
for contaminated seepage joining groundwater can be reduced but not
eliminated altogether under these conditions.
Impact on Socio-economic and Cultural Resources . There would be an
enhanced sense of security provided by more adequate wastewater retention
capacity during cold weather and the resulting improvement in water quality.
-------
V-2 6
The cost of the improvements proposed here would be relatively low,
approximately $40 per household per year. This is well below a reasonable
maximum of one-half of one percent of annual income for sewage treatment
expenditures.
The area in the vicinity of the existing lagoon may contain significant
archaeological resources, therefore more site-specific investigations would be
required prior to the development of any detailed plans.
Impact on Aesthetic Features . Doubling the present lagoon area would
detract visually from the natural landscape value in the area east of Carlisle.
Occasional odor problems would continue in the vicinity of the
treatment lagoons.
Cumming
Proposed Plan: Abandon septic tanks; build collection system and
lagoon.
Impact on Water Resources . Lagoon effluent discharge to the receiving
stream (a tributary to North River) twice yearly would cause minor increases
in suspended solids, BOD nutrients in the receiving stream. The overall
impact of the effluent on North River would be very small.
Impact on Air Resources . No significant impact foreseen.
Impact on Land Resources . Approximately six acres of farmland would
be required for construction of the lagoon and supporting land area.
Additional land corridors would be disrupted temporarily as the collection
system is constructed.
-------
V-2 7
Impact on Biological Resources . No significant impact foreseen.
Impact on Environmentally Sensitive Areas . No significant impact
foreseen.
Impact on Socio-economic and Cultural Resources . The cost of making
these improvements would be disproportionate to the available financial
resources of the community and private customers served. Therefore,
additional funding sources would be required to implement the proposed plans.
Impact on Aesthetic Features . There would be occasional odor in the
vicinity of the lagoon.
Elkhart
Proposed Plan: Expand existing lagoon.
Impact on Water Resources . Expanding the treatment lagoon would
significantly increase the quality of the effluent discharged to South Skunk
River. The most significant aspect of this improvement would be that
wastewater flows could be retained during winter months, when treatment
efficiency in the lagoon is very low, and during low flow conditions in the
receiving stream.
Impact on Air Resources . No significant impact foreseen.
Impact on Land Resources . Approximately two acres of farmland would
be required in addition to the 3.1 now in use for the lagoon.
Impact on Biological Resources . A decrease in BOD of the lagoon
effluent would greatly improve conditions for aquatic animals in South Skunk
River.
-------
V-2 8
Impact on Environmentally Sensitive Areas . The present lagoon site is
close to the southwestern edge of the buried aquifer formed by a pre-glacial
channel of the Skunk River, although the threat to its water quality from
seepage is small due to the glacial overburden protecting it.
Impact on Socio-economic and Cultural Resources . There would be an
enhanced sense of security provided by the improved quality of treated
effluent discharged to South Skunk River.
The cost of making these improvements would be disproportionate to
the available financial resources of the community and private customers
served. Therefore, additional funding sources would be required to implement
the proposed plans.
Impact on Aesthetic Features . No significant impact foreseen.
Granger
Proposed Plan: Expand existing lagoon.
Impact on Water Resources . The existing lagoon system lies over the
alluvial aquifer associated with Beaver Creek and borders on its floodplain.
Expansion of the lagoon system into or along the floodplain would increase
the hazard of contaminated seepage penetrating the aquifer.
Treated lagoon effluent is now discharged to Beaver Creek. Upgrading
the lagoon system would allow more efficient treatment and retention during
cold-weather periods and periods of low flow in the receiving stream. Twice
yearly discharge is proposed.
Impact on Air Resources . No significant impact foreseen.
Impact on Land Resources . Upgrading the lagoon would require
approximately 13 acres in addition to the six now used.
-------
V- 29
Impact on Biological Resources . (See ttEnvironmentally Sensitive Areas”
below.)
Impact on Environmentally Sensitive Areas . The existing lagoon is
located just upstream from one of the few wetland sites in the study area. It
is a shallow depression in the landscape extending for nearly two miles along
the Beaver Creek. Brenton Slough is located in the southeast portion of this
wetland complex.
The wetland contains an abundance of emergent vegetation, which
provides cover and food sources for ducks and other birds as well as small
mammals. As a shallow water system, it is particularly sensitive to changes
in surface and near—surface ground water quality.
Expanding the lagoon into or along the floodplain would increase the
hazard of ground water contamination and therefore the hazard to the
wetland system as a whole. Special precautions during construction and
periodic inspections for leaks or faults in the lagoon system would be required
to minimize hazard to the slough.
Impact on Socio—economic and Cultural Resources . The wetland system
provides recreation for persons interested in hunting and wildlife in general.
Upgrading the lagoon system would also enhance the sense of securty
provided by improved water treatment.
The cost of proposed improvements would be approximately $105 per
household per year.
! pact on Aesthetic Features . Occasional odor would be generated in
the vicinity of the treatment system.
-------
V-3 0
Grimes
Proposed Plan: Improve existing mechanical plant.
Impact on Water Resources . Effluent discharge to Walnut Creek would
take place only during high stream flow conditions. The net impact of this
plan would be to improve water quality in Walnut Creek.
Impact on Air Resources . No significant impact foreseen.
Impact on Land Resources . The land area now used for the treatment
facility would be inereased by two to five acres.
Impact on Biological Resources . Improving effluent discharge would
contribute to improved conditions for aquatic animals in Walnut Creek.
Impact on Environmentally Sensitive Areas . No significant impact
foreseen.
Impact on Socio-economic and Cultural Resources . There would be an
enhanced sense of security provided by cleaner water.
The cost of proposed improvements would be approximately $100 per
household per year.
Impact on Aesthetic Features . No significant impact foreseen.
Hartford -
Proposed Plan: Abandon septic tanks; build collection system and
lagoon.
-------
V-3 1
Impact on Water Resources . The lagoon effluent would be discharged
twice yearly to Butcher Creek, the lower reaches of which are located in the
flood pool of Lake Red Rock. This discharge may contain elevated levels of
suspended solids, BOD and nutrients in relation to those levels in the
receiving stream, and thereby cause a small decrease in the quality of a
downstream portion of the stream. However, discharge during high flow
conditions would minimize any negative water quality impact.
Impact on Air Resources . No significant impact foreseen.
Impact on Land Resources . Approximately 16 acres of farmland would
be used for the lagoon and supporting areas. Construction of the collection
system would temporarily disrupt additional land corridors throughout the
service area.
Impact on Biological Resources . The lagoon effluent is likely to have a
nutrient level which may be greater than that of the receiving stream.
However, only twice yearly discharge from the lagoon is proposed; therefore,
the impact of the effluent, if well treated, would be trival.
Impact on Environmentally Sensitive Areas . No significant impact
foreseen.
Impact on Soeio-economic and Cultural Resources . The cost of making
these improvements would be disproportionate to the available financial
resources of the community and private customers served. Therefore,
additional funding sources would be required to implement the proposed plans.
Impact on Aesthetic Features . The land area used for the lagoon
system would be degraded visually by the structure. Occasional odor would
be generated in the vicinity of the lagoon system.
-------
V-3 2
Mitcheilville
Proposed Plan: Abandon existing plant; construct interceptor to new
lagoon downstream on Camp Creek.
Impact on Water Resources . Discharging higher quality effluent to East
Branch Camp Creek further downstream than at present would substantially
improve the water quality of the stream. Discharge will take place only
during high flow stream conditions when the effluent water quality meets the
prescribed limits.
Impact on Air Resources . No significant impact foreseen.
Impact on Land Resources Approximately 15 acres would be required
for the lagoon. All available land in the vicinity is farmland.
Construction of the interceptor would temporarily disrupt a corridor of
approximately 1,500 feet.
Impact on Biological Resources . The improved water quality would
result in a small but significant decrease in conditions for aquatic plant
growth and a similar increase in conditions for aquatic animals.
Impact on Environmentally Sensitive Areas . No significant impact
foreseen.
Impact on Socio-economic and Cultural Resources . The Thomas
Mitchell County Park begins approximately one mile downstream of the
proposed facility. The impact of the proposed facility would be to reduce the
public health hazard in the Park by improving the water quality of Camp
Creek.
-------
V-3 3
The cost of the project would be approximately $75 per household per
year.
Impact on Aesthetic Features . No significant impact foreseen.
Norwalk
Proposed Plan: Expand existing lagoon.
Impact on Water Resources . The existing lagoon discharges to the
North River. Expanding the lagoon would improve the quality of its effluent
and thereby improve the quality water in a downstream portion of the North
River. Discharge would take place only twice yearly - during high stream
flow conditions.
Impact on Air Resources . No significant impact foreseen.
Impact on Land Resources . Approximately 15 acres are now used for
the lagoon. An additional 42 acres would be required to fully upgrade it.
Most of the land available for expansion is farmland. Expanding the lagoon
system to the south or southeast would destroy valuable protective vegetation
bordering the North River.
1mpact on Biological Resources . Conditions for aquatic animals in the
North River would be improved by upgrading the existing lagoon system and
by retaining treated wastewater during low flow conditions.
Impact on Environmentally Sensitive Areas . No significant impact
foreseen.
Impact on Socio-econornic and Cultural Resources . There would be an
enhanced sense of security provided by cleaner discharge to the North River
and by a facility that could adequately accommodate the projected growth of
the community.
-------
v-34
The cost of the proposed improvements would be approximately $43 per
household per year.
Impact on Aesthetic Features . A threefold increase in lagoon area
would visually degrade the landscape along the North River. Occasional odor
would persist in the vicinity of the treatment system.
Polk City
Proposed Plan: Expand existing lagoon.
Impact on Water Resources . Twice yearly discharge to the Big Creek
would be improved substantially, and this would cause an improvement in the
overall water quality of the stream by eliminating discharge during low flow
conditions.
Impact on Air Resources . No significant impact foreseen.
Impact on Land Resources . Approximately 17 acres would be required
in addition to the eight now used for the lagoon. All available land (excluding
some steep slopes) is farmland.
Impact on Biological Resources . Conditions for aquatic animals in Big
Creek would be improved greatly by controlled discharge and by improved
wastewater treatment.
Impact on Environmentally Sensitive Areas . Expansion of the lagoon
system to or near the steep slopes could cause surface seepage and/or slope
failure.
Impact on Socio-economic and Cultural Resources . Improving the
quality of water treatment would enhance the value of Big Creek as a local
recreational resource. The cost of improvements would be about $72 per
household per year.
-------
V-3 5
Impact on Aesthetic Features . No significant impact foreseen.
Spring Hill
Proposed Plan: Abandon septic tanks; build collection system and
lagoon.
Impact on Water Resources . Treated effluent would be discharged to
Middle River, 16 miles above its confluence with the Des Moines River, but
the threat to its water quality is small because of Spring Hill’s population in
relation to the total discharge of Middle River and because no discharge
would be made during low flow conditions.
The lagoon would be located over an alluvial aquifer lining the River,
therefore, seepage would be a hazard without special protective measures.
Impact on Air Resources . No significant impact foreseen.
Impact on Land Resources . Approximately three acres of land would be
required for the lagoon and supporting land area. Additional land corridors
would be temporarily disrupted in connection with the construction of the
collection system.
Impact on Biological Resources . No significant impact foreseen.
Impact on Environmentally Sensitive Areas . No significant impact
foreseen.
Impact on Socio-economic and Cultural Resources . The cost of making
these improvements would be disproportionate to the available resources of
the community and private customers served. Therefore, additional funding
sources would be required to implement the proposed plans.
-------
V-36
Impact on Aesthetic Features . Occasional odor would be generated in
the vicinity of the lagoon.
Waukee
Proposed Plan: Expand existing lagoon.
Impact on Water Resources . Lagoon effluent would be discharged to
the Upper Sugar Creek, thereby posing an ongoing, small hazard to its water
quality, primarily during low flow conditons in the stream and/or during times
of reduced treatment efficiency in the lagoon.
Upgrading the lagoon would improve the quality of its effluent and
decrease the overall hazard to the water quality of Upper Sugar Creek.
Impact on Air Resources . No significant impact foreseen.
Impact on Land Resources . Approximately 45 acres would be required
in addition to the eight acres now in use by the existing lagoon. All available
land is farmland.
Impact on Biological Resources . With an overall improvement in the
quality of treated effluent, conditions for aquatic plants would decrease
slightly and conditions for aquatic animals should improve slightly.
Impact on Environmentally Sensitive Areas . No significant impact
foreseen.
Impact on Socio-economic and Cultural Resources . There would be an
enhanced sense of security provided by improved water quality in Sugar
Creek.
-------
V-37
The cost of the proposed improvements wou!d be approximately $41 per
household per year.
Impact on Aesthetic Features . No significant impact foreseen.
Energy Requirements
The major energy-demanding activities required to implement the
proposed plan are electrical energy to operate the lift stations in the
collection system (approximately 130,000 kilowatt-hours per year); electrical
energy to operate pumps and control equipment in the areawide treatment
plant (approximately 17 million kilowatt-hours per year); approximately
30,000 gallons of fuel (probably diesel fuel) to operate sludge-hauling trucks;
and approximately 130,000 gallons of fuel oil or its equivalent to heat
buildings associated with the areawide treatment facility.
Impact on Historic/Archaeologic Sites
The 208 Study committee is coordinating review of the potential
impacts of proposed projects on cultural resources with the Division of
Historic Preservation (DH P), State Historical Department.
When specific project sites are identified, they will be reviewed by the
Division. Recommendations made by DHP concerning potential impacts of
the proposed projects, i.e., surveys, intensive investigations, and procedures
for mitigating adverse impacts, will be given consideration and will be
implemented as early as possible in project planning.
Evidence currently available indicates that the Des Moines River Valley
was rather intensively occupied (Gradwohl, 1974). It may be possible to
identify materials indicating cultures as early as 5,000-10,000 years B.C.
There is a considerable amount of material associated with cultures dating
-------
V-3 8
from around the first century A.D. When all of the sites now identified are
thoroughly studied and catalogued, it should be possible to derive important
ecological, cultural-historical, and ethnographic conclusions about early
occupants of this region.
Nearly all of the sites presently identified are within approximately two
miles on either side of the Des Moines River. Many sites have already been
covered by the Red Rock Reservoir or will be covered by the Saylorville
Reservoir. One known site is on the south side of Walnut Creek in the
southwest portion of the study area.
The distribution of known archaeological sites is, of course, strongly
biased toward the projected flood areas of the Saylorville, Big Creek and Red
Rock Reservoirs. Therefore, it is impossible to say that other areas,
particularly along the Des Moines River, do not contain significant archaeolo-
gical sites.
Itis the policy of the Division of Historic Preservation, State of Iowa,
not to disclose the location of individual sites, but rather to disclose general
areas where such sites exist. For this reason, only general areas have been
identified, and specific sites would have to be investigated during Step 1
portions of construction projects.
Economic Impact
The 208 plan and program for the improvement of water quality in the
Des Moines area is designed to serve the area through the year 2000. To
appraise the economic impact of a plan, which is to be flexible and which is
subject to many modifications, on a community, which is heterogeneous in
character and then dynamic and changing, necessarily involves a number of
assumptions if it is not to become so complex as to be meaningless. The plan
consists of a number of interrelated elements which must be considered in
-------
v-39
total even though put together as separate elements. These include the Land
Use Intensity Plan showing the arrangement of the community with a
population of 400,000 in the year 2000, the plans for reduction of point,
intermittent and non-point sources of pollution some of which, such as trunk
sewers and treatment facilities, are quite definite and specific and others of
which, such as regulatory systems for erosion control, may be of uncertain
effectiveness. Finally the plan includes a management program showing the
administrative arrangements, the legal measures, and the financing required
to carry out its recommendations.
It is all of these that make up the 208 plan and program and it is the
economic impact of all of them that is being estimated.
For convenience, in many cases, it is the average situation and the
average population (i.e., that for 1990) that is measured. These measure-
ments must be related to the economic baseline projections incorporated into
the 208 program. Cost estimates for the 208 program are in 1976 dollars.
Economic projects included herein to be consistent are also in terms of 1976
dollars. No attempt has been made to anticipate the extent of continued
inflation.
Economic Baseline Projections
The population of the 208 area was estimated to be 315,000 in 1975 and
to increase to 325,000 in 1980, 367,500 in 1990, and 400,000 in the year 2000.
This estimate is predicated on an increase in employment from 142,000 to
180,500 over this 25-year period. (See Table 11—11.)
Economy Generally
The Des Moines economy is noted for its diversity and for the
steadyness of its growth - 1.5 percent per year for the period 1940 to 1970.
-------
V-40
The community is a government center (the state capital), has a wide-ranging
industrial base, serves as a retail and cultural center for virtually the entire
State of Iowa, h is a major complex of insurance and finance corporations, and
is surrounded by some of the most productive farm land in the world. “Survey
of Buying Power” in its 1976 edition (Sales and Marketing Management, 1976)
estimated that Des Moines was the 42nd most affluent market among U.S.
metropolitan areas in 1975 and that its ranking would be even more favorable
in 1980, rising to 23rd! This was based on estimates of effective buying
power per household.
The employment forecast indicated that manufacturing would not have
a significant growth over the next 25 years, a growth of 14 percent, from
26,000 to 29,700. Employment in transportation and utilities would hardly
change at all and there would not be much change in construction
employment, i.e., from 6,700 to 7,900, a growth of 18 percent.
However, employment increases in the other four categories would be
substantial:
Retail and wholesale trade 27 percent
Finance, Insurance, Real Estate 32 percent
Services and Miscellaneous 50 percent
Government 26 percent
It is clear from these estimates that the economic character of the
community is changing. It is becoming less of a manufacturing center and
much more of a financial service, trade and government center. These trends
inject an even greater measure of stability into the economy.
Income
In 1967 the Offices of Business Economics and Economic Research
Service of the Department of Commerce (OBERS) made projections of
-------
V-41
population and family income for the United States and its major political
subdivisions These estimates when expressed in terms of 1976 dollars
indicated Des Moines Metropolitan Area per capita income at -
$6,600 for 1970
$9,000 for 1980
$11,500 for 1990, and
$15,000 for 2000.
Applying these per capita estimates to population estimates results in
total income for the 208 area of -
$2,520,000,000 in 1976
$3,051,000,000 in 1980
$4,255,000,000 in 1990, and
$6,000,000,000 in 2000.
Family Income
Because of decreases in births and changes in life styles, the average
family size has been decreasing. This makes the number of households grow
more rapidly than total population. In the Des Moines Metropolitan Area, the
average number of persons per family decreased from 3.10 in 1960 to 2.98 in
1976. It is likely that this decrease will continue and it is estimated to be —
2.86 in 1980
2.75 in 1990, and
2.67 in 2000.
By multiplying projected per capita income by the respective projected
family sizes, one obtains an estimate of family income as follows:
-------
V-42
$19,200 in 1976
$25,700 in 1980
$31,600 in 1990, and
$40,000 in 2000.
The total disposable income (“Effective Buying Income”) in the Des
Moines metropolitan area for 1975 was estimated as being approximately
$16,300 per household (1976 Survey of Buying Power, 1976). The 1980
projection of disposable income made by the same group is $23,770 per
household.
Distribution of total income among families is quite uneven. If
improvement of water quality is financed by user charges, poor families who
use as much water as rich families must pay a considerably higher percentage
of their income. The most recent data on family income (1969) showed that
45 percent of Des Moines area families had incomes under $10,000 for that
year; 32 percent between $10,000 and $15,000; and 19 percent between
$15,000 and $25,000.
Wastewater Treatment Expenditures
While no hard and fast rule may be involved to determine a reasonable
level of expenditures for wastewater treatment or for improvement of water
quality, some guidance may be obtained by examining past levels of
expenditure.
The Des Moines Metropolitan Area may be compared with seven other
middle west metropolitan areas (see Table V-i) for the 1971-1972 fiscal year.
The Des Moines area total sewerage expenditure per capita was $13.49 the
mean of the eight cities was $18.35. Des Moines expenditures were 0.28
percent of gross personal income in comparison with an average of 0.43
percent for the eight metropolitan areas. This study indicates that 0.50
-------
V-43
Table V-I
PERCENT OF PERSONAL INCOME SPENT ON SEWAGE TREATMENT
1970—1971
Des Moines and Seven Other Midwest
Metropolitan Areas
Total
Per Capita Sewerage
Sewerage Per Capita as a Percent
Area Expenditure Income of Income
Des Moines $13.49 $4,747 0.28
Omaha 21.89 4,367 0.50
Peoria 6.04 4,821 0.13
Madison 25.85 4,497 0.57
Appleton 20.38 3,980 0.51
Duluth—Superior 15.77 3,834 0.41
Evansville 15.51 4,036 0.38
Fort Wayne 23.02 4,550 0.50
Mean 18.35 4,354 0.42
Sewage expenditures from U.S. Census of Governments, Local Govern-
ment in Metropolitan Area, Vol. 5, Table 12.
Per Capita Income derived from Area Economic Projections, 1990,
U.S. Department of Commerce. Income derived from 1967 dollars.
-------
V-44
percent of personal income may be a reasonable upper limit of an acceptable
expenditure for sewage treatment. While the “metropolitan area” (SMSA) and
“208 area” are not coterminous, SMSA data comes closest to indicating
conditions in the 208 area.
In 1976, in the 208 area, 285,000 persons were served by municipal
sewerage facilities having a present worth of approximately $105 per capita.
Capitalized at 20 years at six percent interest, this represented an annual
cost of $8.50 per capita. Operation and maintenance costs were $3,442,000
or $12.08 per capita, making a total of $20.58. This was 0.26 percent of the
estimated 1976 per capita income. Approximately 104 persons were
employed in sewage treatment in 1975.
General Impact of Water Quality on Economy
“Clean Water” is an important element in the environment and to
eliminate most water pollution will improve living conditions. With industries
and business enterprises (such as insurance companies) having a wide range of
choice as to location, clean water would give the community a competitive
edge in this economic competition. The secondary impact in enhancing water
recreation opportunities would be of equal importance.
A similar result would come from the ability of the area to organize and
coordinate 26 units of local government toward a common purpose. This
could not help but be an attraction also.
One of the greatest difficulties in industrial operation stems from
uncertainty concerning governmental actions. If an industry can be certain of
the requirements that are to be placed upon it in regard to water quality,
what it will need to do and what it will cost for example, it is better able to
plan its operations and their financing. A reliable program for water quality
improvement consistently carried out would provide an important factor of
certainty for industrial operations.
-------
V-45
Financial Aspects of the Plan
Economic impact of the 208 program will result from its costs and its
benefits and these in turn will vary in their effects depending upon the means
used to finance the program.
Financing Mechanisms Generally . Three general methods are utilized in
financing wastewater management. These are:
1. Financing the wastewater treatment and management by the
utilization of conventional taxation.
2. Imposition of fees such as building permits or, particularly,
connection fees. By making a fee for connection of a new building
to a sanitary sewer sufficiently high, the new building may be
required to pay its proportionate share of previous investments in
the system.
3. User charges. Wastewater collection and treatment may be looked
upon the same way as any other utility and charges made to each
individual user or discharger based upon the volume of waste that
he contributes.
User charges may have many variations. The Environmental Protection
Agency has regulations concerning these where there is Federal funding of
the system. EPA regulations forbid the lowering of rates (decreasing Step—
rates) for the larger water users but demand that the rates be imposed on a
per-gallon formula. Sometimes user rates are varied to take into account the
quality of the wastewater going into the system (amount of treatment
needed) or to take into account the distance that the wastewater has to be
transported from its source to the treatment plant. It is also possible to use
several types of user charges such as a flat charge for administration and
-------
v-46
then a per-gallon charge for operation and maintenance, for treatment and
for capital expenditures.
A “fourth method”, which may or may not be available in the future, is
to seek Federal and State construction grants for financing of capital
improvements through EPA. Where these are available they can finance 80
percent of the cost of the improvement (75 percent Federal, five percent
State). Applications are submitted to the Environmental Protection Agency
which distributes funds (available partly at least from federal taxes collected
locally) appropriated by Congress on a nation-wide basis. Distribution within
Iowa is determined by a priority system administered by the State
Department of Environmental Quality. These funds have played a very
important part in recent construction. Some improvements may be financed
by loans and grants from the Farmers’ Home Administration for smaller
communities or from grants from the Community Development Program of
the Housing and Urban Development Department.
Capital costs of building a system may also be financed by a number of
local methods. One of these, of course, is to impose additional taxes, fees or
charges and to finance capital improvements on a “pay-as-you-go” plan. A
second method is to issue general obligation bonds and to retire these bonds
from a tax against either the entire community or against a special district
benefiting from the particular improvement. Special assessments are
frequently used for the laterals and collector elements in a sanitary sewer
system. A final method of financing the improvements is through issuing
revenue bonds. Where revenue bonds are used, the user charges must be
sufficient to pay for the administrative, operation and maintenance costs of
the agency and for the amortization of the bond issue itself. Bond ordinances
may require that reserve funds be established to make the bond issue more
attractive. Finally the bond “coverage” for the amount of income pledged to
the bond issue should be 1.2 to 1.5 times the annual amortization costs of the
bond issue.
-------
V-47
General obligation bonds which are backed up by a real estate tax may
be issued for a lower interest rate (sometimes one-half of one percentage
point less) than the r venue bonds. Over a 20-year bond-issue period,
utilization of the general obligation bond results in a rather considerable
saving of interest costs. A particularly desirable financing method is to issue
general obligation bonds at the lower interest rate and then to utilize the user
charges to retire them.
At the same time, user charges are not deductible from personal income
taxes. These charges are deductible from commercial and industrial taxes
because they are a business expense. The average income tax is 17 percent.
Assuming an annual per capita cost of $25.00 for wastewater purposes with 40
percent or $10.00 for capital improvements, the 80 percent federal and state
grant would ttsavett $8.00 while the tax saving that would result from a real
estate tax rather than a user charge would be $4.25. Thus utilization of the
EPA and DEQ grants and the imposition of the user charges would be very
much to the advantage of the taxpayer.
Estimated Costs
Point Source construction costs for the ICA (Integrated Community
Area) are estimated at $112,114,000 for Alternate Plan VIII - the chosen plan.
Point source costs for the 13 outlying communities total $4,120,000 but each
outlying community is to be considered individually. Of the ICA point-source
construction costs, $84,100,000 would be financed by an EPA grant and
approximately $5,600,000 by a DEQ grant leaving $22,423,000 to be financed
locally. Annual operation and maintenance for trunk sewers and sewage
treatment would be $5,341,000 and for the lateral sanitary collection system
$1,327,000, a total of $6,668,000. In addition the present indebtedness
incurred by the communities in the ICA is $9,884,000. Adjustment would also
be made for industrial cost recovery charges. Thus the annual cost would be:
-------
V-4 8
Point source construction (revenue bonds) $ 2,825,000
Point source operation and maintenance 6,668,000
Annual cost assumption of present debt 890,000
Adjust for industrial cost recovery - 71,000
$10,312,000
Intermittent source pollution mitigation measures would include
segregating the sanitary flow from northwest Des Moines, Camp Dodge,
Lovington, Urbandale-Beaver Creek, Johnston, Saylor Township and West
Ankeny by routing the flow through a new interceptor sewer (force main) to
be constructed parallel to the Westside Interceptor which presently received
flow from combined sewers. Flow from the combined system would enter the
main outfall to the treatment plant up to a point where the dilution ratio is
five to one. Flows in excess of five to one would be diverted to the combined
sewers with flow separators constructed at each of the combined sewer
overflows and at strategic storm sewer discharges. Total construction cost
for this program is $3,487,000. Operation and maintenance js estimated at
$56,000 per year and total annual costs at $385,000 per year.
Non-point pollution source mitigation proposed would include:
1. Promotion of cropland runoff central options;
2. Construction site erosion controls; and
3. Reductions in urban development in unincorporated areas.
Within the 208 area cropland runoff central expenditures are about
$125,000 per year. The program calls for an increase of $1,000,000 per year,
half of which would be provided by the state and federal governments and
half by the individual farmers participating in the program.
-------
V-49
Construction site erosion controls are estimated to add $250,000
annually to the cost of construction in the Des Moines 208 area. Admin stra-
tion and enforcement would be carried out by existing personnel as would the
program to reduce urban development in unincorporated areas.
Cost Per Capita
The estimated cost of the 208 program on a per-capita or per-family
basis will vary in different parts of the 208 area. These costs should not be
confused with user charges which may be ccnsiderably reduced by the
commercial and industrial cost-sharing corrections.
For the integrated community area , annual costs (exclusive of the non-
point program total $9,127,000 per year), the 1990 (average) ICA population is
estimated at 331,700, the cost per capita per year would be $45-50; the
average cost per family would be $130. The cost for wastewater treatment
would be approximately $1.00 per gallon.
For the outlying communities , the annual costs per eapit and per
family would be:
Per Per
1990 Capita Family
Community Annual Cost Population Cost Cost
Alleman 30,000 270 111 307
Carlisle 50,000 3,500 14 39
Cumming 23,000 260 88 244
Elkhart 16,000 325 49 135
Granger 42,000 1,100 38 105
Grimes 70,000 2,000 35 97
Hartford 77,000 700 110 304
Mitchellville 56,000 2,100 27 74
Norwalk 58,000 3,700 16 43
Polk City 30,000 1,080 28 77
Rur inells 50,000 585 85 236
Spring Hill 22,000 150 147 405
Waukee 40,000 2,700 15 41
-------
V-50
The wide disparity in these per capita costs makes financing of these
systems by some of the communities most questionable. Annual costs shown
are exclusive of state and federal grants.
Cost as a Percent of Income
Exclusive of the non-point program local costs of the 208 program for
the ICA of $45-50 per capita amount to 0.41 percent of total income.
In the following outlying communities the estimated per capita costs
are disproportionate to income: Alleman, Cumming, Elkhart, Hartford,
Runnells and Spring Hill. Financing of the program by these communities
with each one “on its own” would be most difficult unless further assistance
from state or federal grants would be obtained.
The outlying communities and the agricultural areas would assist in
financing their part of the administrative, planning, coordination and priority
setting activities. These costs are expected to amount to roughly $300,000
per year. The assessed value of the 208 area is not known. The Polk County
assessed value totals $3,591,968,000. If financed by a real estate tax, the tax
rate would be .00835 percent to raise the $300,000 in administrative expenses
based on Polk County assessed value alone. The assessed value of tl e
unincorporated areas of Polk County is $454,523,000; there are about 1,350
farms.* With an assessed value of $200,000, the administrative cost of the
208 program per farm would amount to about $16.70.
Employment Generated
The water quality improvement program is anticipated to have an
employment of about 150 by 1990, or 0.6 percent of the public employment of
23,500 anticipated for the 208 area for that date.
* 1,374 in 1969 Census of Agriculture.
-------
V-5 1
The total amount of construction anticipated in the 208 program is:
$130,827,000 point sources ICA
6,057,000 point sources outlying communities
3,487,000 intermittent ources
5,000,000 construction erosion control
$145,371 ,Q00
This is an average of $7,269,000 over a 20—year period. Based on a
construction work year of 1,400 hours and the generation of 35,000 man hours
qf work for each $1,000,000 of construction, the 208 construction program
would result in th employment, on the average, of 182 per ons. This is 2.4
percent of the estimated 1990 employment jfl the construction category.
The non-point program for the agricultural areas would require an
increase in the number of perspns skilled in soil conservation and manage-
ment, but the exact number is not determined.
Summary
The 208 program would not involve a significantly increased level of
expenditure for water quality purposes in the area or any great increase i
employme 9 t in either administration or construction. Any economic impact
is more likely to t e found from a more detailed examination of the program.
Conclusions
General . Tbere would be very little impact from increases in public
employment resulting from the 208 program. However, federal financing of
the construction program would support 130 of the 182 construction workers.
With such “outside” financing, each of these would support at least an
additional service employee and the resulting population increase thus
-------
V-52
occurring would be an addition of about 700 persons, hardly a significant
“impact”.
Industry . The impact of the 2O8 program on industry can be significant
because of the industrial cost recovery requirements of EPA. These
necessitate arrangements that recover from industries their proportionate
part of that part of the capital expenditures for waste treatment and
collection facilities financed by EPA. These requirements are complex and
their exact impact on an individual industry would require a long and detailed
study. Industrial cost recovery is not required for any enterprises discharging
only domestic wastes into the treatment facility. Nor are these charges
made against direct discharging industries unless these connect to an EPA
financeç treatment facility.
Seven major industries discharge cooling water only. Ten industries
discharge directly and nine of these could connect. with the new treatment
plant in which event industrial charges would be required. There are 20
industries discharging to the Des Moines main treatment plant that pay a
special sewage charge today. Special surcharges are imposed when the
sewage discharged is particularly strong in BOD or suspended solids. These 20
industries have a total employment of about 4,750, at?out 18.3 percent of the
current industrial employment of 26,000. The total industrial payments to
the City of Des Moines in 1976 were $288,000. However, additional charges
are being imposed in 1977 that will add $306,000 making the total charge
$594,000.
The new wastewater treatment plant is estimated to cost $47,890,000.
New trunk sewers, equalization basins, pump stations, etc., are estimated to
cst $51,971,000, a total of $99,861,000. The EPA grant is estimated at
$73,379,000. An industry would pay the usual user charge of about $1.00 per
1000 gallons of water used . Then it would pay its part of the EPA grant for
the treatment plant and the trunk sewers. With a recovery period of 25
-------
V- 53
years, the annual cost of the EPA grant would be $293,516. With industry
using four of the 50 mgd average flow of the plant, the annual cost recovery
charge would be $23,500. With the industrial discharges averaging three
times the strength of domestic sewage, the total annual industrial cost
recovery charge would be about $70,500 per year. This would add about 7
to the $1.00 per 1000 gallon user charge for the average industrial user .
Much would depend, however, upon the waste characteristics of the
individual industry’s discharge. Eight food processing plants with a total
employment of a little under 1000 would be likely candidates for pre-
treatment. The precise impact could only be determined by a detailed
analysis of each industry. It would not appear that industrial cost recovery
charges would have an adverse effect on the competitive position of the Des
Moines area for industry. Nor is it deemed likely that any existing industry,
with possibly one exception, would move to another location because of the
charges imposed by the 208 program.
Residential Users . Previous studies show the wide variation that exists
in water and sewer charges made in the 208 area. (See Table 111-2, Phase 2,
Interim Report.) The 208 program would not change the water rates.
However, for the ICA all sewer charges would be billed and collected through
the water supply organizations. These charges would pay for the transport
and treatment of the sewage. Remaining responsibilities for the lateral
sewer systems and storm drainage would be financed by connection charges
and conventional taxation or by additional user charges.
The average person is expected to use 65 gallons of water per day. At
2.75 persons per family, the average family use would be 65,000 gallons per
year. At $1.00 per 1000 gallons, the annual sewer charge would be $65.00 per
family. This would be 0.185 percent of the average family income in 1990.
A sewer charge is regressive in that it falls more heavily on the poorer
families than on the wealthier. The $65.00 per family charge is only 0.26
-------
V-54
percent of the income of a family making $25,000 per year while it is two and
one-half times as high a percentage of the $10,000 a year family.
Unfortunately family income data is too far out of date to enable an analysis
of these impacts. Studies in larger metropolitan areas have shown that per
capita water use increases as family income increases although not in exact
proportion. With the user charge on a per-gallon basis irrespective of the
total quantity used, there will be a tendency for the charge vs. family income
to even out somewhat although it is not possible to determine just how much.
Outlying Communities . The 208 area includes 13 outlying communities.
Four have no sewer system at all. Four have estimated 1990 populations of
less than 500, two of between 500 and 1,000 and only four more than 2000.
Data on family income is lacking but the average family income in these
communities is probably less than the average for the remainder of the 208
area. Assuming that the average income in these communities would be the
same as the $11,700 average for 1990 and that a reasonable maximum for
sewerage expenditures is roughly one-half of one percent of income, then any
program that costs more than $58.50 per capita per year could not be self-
financed. On this basis the following programs could be self—financed:
Carlisle Norwalk
Granger Polk City
Grimes Mitcheilville
Waukee
The remainder would require additional Federal, State or local
assistance.
Unincorporated Areas and Communities Without Collection Systems .
There are nine communities, five incorporated and four unincorporated that
have no collection systems at all. The unincorporated areas would have to be
annexed or the counties would have to be given the power to build the
-------
v-5 5
collection systems in the unincorporated areas. Financing of the collection
systems would be by benefit assessments against the area served. Because of
the characteristics of these areas, 10-year assessment bonds bearing an eight
percent interest are assumed to be required. These collection systems are
needed as soon as possible in order to eliminate the septic tank difficulties in
these areas. Capital costs have been estimated. The result would be:
Annual
1980 Cost Per
Annual No. of Family
Service Area Cost Cost Families for 10 years
Bloomfield Twp. 624,000 87,360 950 92
Cumming 147,100 20,595 76 271
Delaware Twp. 3,025,000 423,490 900 471
Hartford 592,500 82,950 220 377
Johnston 1,664,500 233,030 1,120 208
Lovington 405,750 56,805 420 135
Saylor Twp. 4,685,000 655,890 1,575 416
Spring Hill 166,400 23,295 50 466
W. Bloomfield Twp. 130,000 18,200 185 98
In most instances these charges would severly deteriorate the value of
the area for residential purposes and would inhibit further residential
construction within them. This program would thus have an impact on the
general growth trends in the metropolitan area. It would have to be
accompanied by stringent regulations of the use of septic tanks such as a
minimum five or ten acre lot, otherwise the problem areas would just move to
new locations.
Agriculture . As previously noted administrative, planning, priority and
coordination activities of the AWA would cost the average farmer $16.70 per
year. A major element of the non-point program would be reduction in
pollution from cropland runoff. This program would have a major impact on
the agricultural areas.
The soil and water conservation programs, as administered by existing
agricultural agencies, are reducing the effects of cropland runoff on the
-------
V-56
water quality of streams and lakes. A program administered by the Soil
Conservation Districts considers the use of all available conservation
practices in an overall farm resource management program. For each farmer
who agrees to become a SCD cooperator, SCD personnel develop alternate
conservation systems to bring soil losses for the farm within tolerable limits.
Each participating farmer then has the opportunity to select a system for
implementation. In this way, to become eligible for funding, farmers must
agree to become cooperators in whole with their respective Soil Conservation
District.
If the control options considered in the 208 Program were implemented
over the entire 208 Study Area, the waste loads transported from croplands to
receiving surface waters would be reduced by at least 60 percent. Problems
associated with complete implementation of conservation programs include
the availability of sufficient funds for cost-sharing programs, a lack of land
contractors to do all the needed land reshaping such as installing terraces,
and need to follow several deviations from conventional farming practices
which have been in existence for several decades. If these problems could be
overcome, the trend towards the adoption of conservation farming practices
may be increased. Such an increase would result in significant improvement
in surface water quality within the 208 Study Area.
For the entire Study Area, approximately 180,000 acres of cropland
should be terraced to reduce the pollutional potential and to maintain the
productive capacity of the associated land. Within Polk County there are
presently 900 acres of cropland with tile outlet terraces and 3,200 acres of
cropland with graded and parallel broad base terraces which will eventually
be converted to tile outlet systems. Within the Dallas and Warren County
sections of the Study Area, the number of acres presently terraced are also
negligible as compared to the total number of acres which should be terraced.
Most, if not all, of the terraces which will be constructed in the future will be
tile outlet terraces.
-------
V-57
Approximately 8,300 additional acres of terraced land will be construc-
ted by the year 2000 under the existing programs. With the equivalent
number of acres of tile outlet terraces presently being approximately 3,000
acres and assuming that approximately 8,000 acres of eropland which need
terracing will be developed to urban IDP categories by the year 2000, a
subsidy program would need to promote the construction of approximately
161,000 acres of terraces.
In addition to terraces, many grade stabilization structures need to be
constructed within the Study Area for the stabilization of stream banks.
Within Polk County, the existing 158 grade stabilization structures represent
approximately one-third of those needed. Therefore, approximately 300
grade stabilization structures need to be built within Polk County. If this
figure is extrapolated based upon cropland acreages, approximately 470
additional grade stabilization structures need to be built within the Study
Area. By the year 2000, under existing programs, 125 additional grade
stabilization structures will have been built. Therefore, the construction of
approximately 350 grade stabilization structures would have to be promoted
through a 208 program. If it is again assumed that a funding program will
begin in 1978, approximately 15 grade stabilization structures would need to
be built yearly, if all the needed structures are to be installed by the year
2000.
The 208 program contemplates a more than 10-fold increase in the soil
conservation subsidy program to $1,125,000 annually in the 208 area. This
assumes 50 percent cost sharing, terracing to cost $300/acre terraced, and
grade stabilization structures to cost $10,000/structure. The calculations are
based upon a 23-year program which is to begin in 1978 and end in the year
2000. Seven thousand acres are to be terraced yearly or 161,000 acres by the
year 2000, and 15 grade stabilization structures are to be built yearly or
approximately 350 by the year 2000.
-------
V- 58
The cost of a subsidy program represents 50 percent of the construction
cost. The other 50 percent of the construction cost must be provided by the
property owners. In addition, the design cost incurred by SCS has not been
accounted for in the 208 program. Certainly, additional manpower would be
required by SCS to design terraces under a subsidized program. Manpower
requirements may increase as much as twenty—fold.
There should be an economic incentive if farmers are to install
terraces. The present construction cost to the farmer for terracing is
$150/acre. This present cost is equivalent to a 20-year uniform annual cost
of approximately $l4lyear at seven percent interest. Therefore, if the
combined effects of reduced farming costs or increased yields can produce an
additional $14/acre/year for the farmer, there should be an economic
incentive for the farmer to install terraces. There may be some maintenance
costs associated with terraces; however, these are generally regarded to be
very minor. The combined effects of decreased power costs due to contour
farming, decreased fertilizer losses, moisture conservation, increased yields,
and topsoil conservation provide such an economic incentive.
With the agricultural run-off program being voluntary, its true scale and
scope will depend upon the participation of the individual farmer. He will
determine its economic benefit as he will pay one-half the cost.
Summary . The economic impact of the 208 program appears limited
primarily because of the extraordinary health of the general economy of the
208 area. The program itself would be well below the amount the area could
afford to spend on water quality. Negative impacts would appear to be
limited to:
1. A few industries (with a total employment of about 1000) affected
by industrial cost recovery or by the necessity to install pre-
treatment systems. The 208 program as such is not expected to
-------
V-59
generate any removals or abandonment of such industries particu-
larly when some of them (the dairies) are of a service nature.
2. Requirements for additional financing assistance for sewage sys-
tems for some outlying communities.
3. High costs of installing lateral sewers in certain unincorporated
areas and outlying communities which again may require additional
financing assistance.
Adverse economic impacts have been virtually eliminated by the
proposed management plan and its proposed areawide wastewater agency and
its areawide financing systems. If such a system is not used, financing by
local governments no matter in what combination cannot help but interject
economic variables that would help certain cities and hurt others and by so
doing artifically change the relative positions of different parts of the 208
area for different purposes. The proposed management system which
generally treats everyone alike will have an economic benefit.
Economic benefits from the 208 program include a superior environment
and a certainty regarding long-range wastewater requirements that will assist
in attracting new industry to the Des Moines area, at least to the extent
previously predicted and perhaps to an even more rapid growth rate.
Social Impact
General
The economic impact study included projections of populations, families
and individual and family income over the planning period. Anticipated
changes in the age distribution of the population are also significant to the
social impact. (See Table V-2.) Between 1970 and 2000 the 30 to 39 age
-------
V-60
Table V-2
ANTICIPATED CHANGES IN AGE GROUPINGS
OF POPULATION
Des Moines, Iowa 208 Area
Percent
Change
Age Group 1970 1980 1990 2000 1970—2000
0— 9 55,500 53,400 62,100 67,600 +21.8
10—19 58,100 55,900 51,800 56,300 — 3.1
20—29 45,800 59,500 55,500 60,400 +31.6
30—39 33,600 50,400 62,300 67,800 +102.0
40—49 35,000 34,000 50,100 54,500 +55.6
50—64 42,600 48,000 46,300 50,400 +18.4
65 and
older 29,400 34,300 39,400 43,000 +46.3
total 300,000 335,500 367,500 400,000 +33.3
Projection is an adjustment and extension of those made for the Des Moines
SMSA by Real Estate Research Corporation.
-------
V-6 1
category is expected to more than double. The next highest increase would
be in the 40 to 49 age category, a growth of 56 percent. There would be a
significant increase in the elderly (46 percent) and a small decrease in the
number of persons 10 to 19 years of age. These projections are relevant to
estimates of persons per household, number and size of housing units required,
etc.
Community Cohesion and Identity
The 208 area has an interesting organization. The population of 315,000
in 1975 is expected to increase to 400,000 by 2000, a growth of 85,000. The
number of families would increase from 108,250 to 150,000.
Des Moines and the six immediately adjacent suburbs are expected to
grow from 253,000 in 1975 to 293,000 in 2000, accommodating a little less
than one-half the expected growth. In the more outlying parts of the 208
area, there are 13 “satellite” cities, separated from the central urban
complex. These have been growing rapidly in recent years and, as a total, are
expected to almost double in population by 2000, going from 33,500 to 65,700
and accommodating three-eights of the new growth. This is expected for the
following reasons. The small towns were originally service areas for the
agricultural areas around them. They have an attractive “small town”
character. Living in them is cheaper than living in the urban center. They
have their own school systems. “Big-city” problems are gone. In order to
keep the benefits of such an arrangement, the individual community identity
needs to be preserved.
Other growth is anticipated for seven major unincorporated areas, to
increase from 12,700 persons to 32,900 persons, and for the rural non-farm
population, to increase from 7,500 to 11,800 persons. Basic difficulties result
from both these trends. There are serious economic problems in providing
-------
V-6 2
lateral sewers to the unincorporated areas. Further additional scattered
rural non-farm development cannot help but displace agricultural land. Both
trends are inimical to optimum development of the 208 area.
The facilities plan, however, imposes some adverse effects insofar as
community identity is concerned. These are the result of the long trunk
sewers that would connect Altoona and Bondurant with the central treatment
plant, and two long trunk lines connecting to the two Ankeny treatment
plants. These tend to partially destroy the identity of these three
communities and serve extensive areas that should remain in agricultural use.
These trunk sewers and the new trunk line south of the City of Des Moines
that serves the Lakewood area will generate serious land use control problems
if the Land Use Intensity Plan is to be maintained.
Public Participation
Effective public involvement in the water quality improvement program
should be a result of the more decentralized management system. This will
require the participation of the local public officials and is designed to
generate more public interest by maintaining the maximum amount of
community identity.
Housing Conditions
The 208 program would be a major element in the improvement of
housing conditions.
Sewer Back-ups . The growth pattern of the Des Moines area in recent
years has resulted in development of lands at fairly high intensity at the outer
limits of watersheds. Sewer capacity has been tistretchedri to accommodate
this growth. Foundation and roof drains have found their way into sanitary
sewers. The result has been sewer back—ups that plague rather large parts of
-------
V-63
the urban area. These cause health hazards and loss of confidence in the
neighborhood. (See Plate V-2.) Many of the sewer back-up areas correspond
with areas occupied by the lower income groups.
The 208 program proposes construction of 13 “equalization basins” at a
cost of $10,000,000. These basins would relieve the overloaded sewers at
critical times and eliminate the basement back-up problem. A program to
remove foundation and roof drains and to lessen water usë would be of
assistance also.
Foundation and Roof Drains . The only practical solution to removing
foundation and roof drain flows from the sanitary sewers is by ordinance
and/or by making a separate charge for those that discharge to the sanitary
collection system. Such charges (for existing buildings) would have to be high
enough to discourage the continuation of this practice. Costs related to
rehabilitation on private property are not eligible for Federal or State grant
funds under EPA and would have to be paid by the Owner or in conjunction
with a locally financed program. However, it is possible that Community
Development or Public Works funds could be used or that property owners
could give the city a sufficient easement to make the activity eligible for
public funds.
The options available include the following:
1. Identify and locate all roof drains and foundation drains and require
by ordinance one of the following:
(a) Disconnection by the Owner at his expense.
(b) Disconnection by the Owner at Owner’s and local government’s
expense (a maximum limit could be established).
-------
Is
5
• :5 .
‘S .‘
I.. ‘z 1 .
• 1
ii
S
SEWER BACK-UPS
LEGEND
REPORTED SEWER BACK-UPS
PRIME
= LISHED
IOWA
MENT
SERVICE AREAS
BY THE CITY OF
FOR COMMUNITY
PROGRAMS.
AS ESTAB-
DES MOINES,
DEVELOP-
ts.• .5
• . S.
I
5
• S.
S
S
St’s.
•
5.
•.
S’S
•‘!
‘U
I
•
I
S
.
S
S
•
.
S
•5
PLATE V-2
-------
V-65
(c) Disconnection by the Owner (with prior approval) at local
government t s expense.
(d) A charge could be added to the sewer use fee for the service
based upon the size of the area drained if the flows could not
be economically disconnected.
2. Evaluate the sewer capacity required and/or construct equalization
basins to handle the increased flow from these sources and
rehabilitate the collection system where necessary. Leave all
foundation and roof drains connected.
(a) Increase the sewer use fee.
(b) Make a charge to those Owners with foundation or roof drains.
The above alternatives appear severe; however, flows from these
sources create economic hardships to individuals who experience basement
flooding as well as representing a higher cost to the entire population due to
increased capital and operation costs necessary to transport and treat these
extraneous flows.
The removal of foundation drains and roof connections is being
addressed separately under Sewer System Evaluation Surveys being conducted
by individual communities where excessive infiltration/inflow or clear water,
such as that emitted from foundation drains and roof connections, has been
determined.
With adequate education and participation and with imaginative
financing, it should be possible to make a major improvement in these
conditons.
-------
V-6 6
Water Conservation . Water can be conserved in the home, commercial
establishments and industries by various control techniques. A substantial
reduction can be realized through the use of flow restrictors on water faucets
and shower heads. Devices such as these can result in water savings of 50 to
70 percent and have been termed “effective” by EPA studies. Water-saving
toilets can conserve water by improved float assemblies, reservoirs which
hold less water (3.5 to 2.5 gal), dual-flush-cycle - that is one cycle for solids
and one for liquids (2.5 and 1.25 gal.) and vacuum system type toilets which
recycle a portion of the wastewater.
Other water conserving devices include a premixed hot and cold water
fixture which delivers water at a preset temperature, pressure reducing
valves and waterless toilets. With the use of the above mentioned flow
controls an average household could expect a water savings of approximately
30 percent.
The primary use of these devices is in future building construction and
it is doubtful if a significant impact could be made on existing homes and
buildings.
A natural trend is occurring in industry and manufacturing companies to
conserve water. In some cases, the quantity of water wasted is not known to
management and industrial water and wastewater surveys can be helpful in
locating possible areas where significant savings can be realized. Such
surveys could become a service provided by either the water or wastewater
management utility in conjunction with either the gas or electrical utility.
An important aspect of water conservation is the voluntary willingness
of the public to use less water than they now use. This can be accomplished
through public education programs which are aimed at changing established
habits. The consumer should be aware of water supply, treatment,
transmission and storage costs as well as wastewater collection and
-------
V-6 7
treatment costs incurred by wasteful use of water. Awareness of pollution
resulting from wasteful use of water can be accomplished through interested
voluntary organizations, pamphlets inserted with the sewer bills and a
variation of posters for schools, buses, billboards, etc.
Mobile Homes . In the United States in 1976 of the 1,500,000 new
dwelling units provided 270,000 or 18 percent were mobile homes. These have
become an important means of providing owner-occupied housing for
moderate and lower income families. In the Des Moines area generally,
mobile homes are required to be located in a mobile home “park”. For the
most part these parks have located in unincorporated areas and have provided
their own sewage treatment. Of the ten “parks” in the 208 program, eight
employ one or two-cell lagoons and two utilize extended aeration package
treatment plants. Placing these “parks” in outlying, rural environments is
socially undesirable. Adverse effects may be mitigated by better site
planning. Locations in urban areas where they may connect to municipal
wastewater treatment facilities should be chosen.
Recreation
A major social benefit from the 208 program will be the recreation
benefits from improved water quality. “Outdoor Recreation in Iowa” (Iowa
Conservation Commission, July, 1972) indicated that approximately 80
percent of Iowans over 12 years of age picnic, 30 percent boat, 20 percent
fish, and 10 percent hunt. Significant increases are observed in the use of
almost all outdoor recreation facilities. The 1972 report estimated 1980
activity days for Central Iowa (Region VII) as follows:
Family picnicking 4,300,000
Fishing 2,800,000
Pleasure boating 1,700,000
Swimming 1,100,000
Camping 1,100,000
Water Skiing 300,000
-------
V-68
This study noted severe deficits in facilities provided for picnicking,
swimming and camping.
The City of Des Moines is notable for the extensive parks along the
Raccoon River. The city with the assistance of grants from the Bureau of
Outdoor Recreation is vigorously pursuing a program providing public parks
along all of the Des Moines River. The Land Use Intensity Plan specifies such
an arrangement and, in addition, proposes public open space or permanently
reserved open space along all of the major streams and drainageways.
Major recreational opportunities are provided at Lake Red Rock and
will be provided at Lake Saylorville. A major benefit to be derived from the
Des Moines 208 Program is improvement in water quality at Lake Red Rock.
Reduction of suspended solids and sediments would be of material assistance
in improving the water quality and hence the usefulness of this reservoir.
Improved water quality on the Des Moines and Raccoon Rivers would
enable them to be used extensively for such purposes as boating and fishing in
addition to enhancing their aesthetic value. Within walking distance or a
short driving distance of the metropolitan population, these rivers can provide
needed recreation and reduce energy use. With hiking, bicycling and riding
trails along the rivers, streams and major drainage areas an entire new
transportation and recreation system may be provided interconnecting all
parts of the urban area. Such a system could not even be considered if the
water quality is poor and the environment unpleasant. These green areas
along the rivers and streams would provide excellent wildlife habitat as well.
With good water quality, all of these possibilities for recreation may be
realized. Without good water quality none are possible.
Aesthetics
For the most part, the facilities required for water quality improvement
would be buried underground, hidden away in unobtrusive locations or
-------
V-69
screened, or located in industrial areas such as the new central treatment
plant. New trunk sewers that would have to be built along streams or
drainageways would be located to do the minimum damage to the natural
environment. (See Chapter VI.)
Summary
Social benefits of the 208 program would come from:
1. The management program which would encourage retention of
community identity.
2. Greatly enhanced outdoor recreation opportunities.
3. Aesthetic benefits from open space along rivers, streams, and
drainageways with water of gcod quality.
4. Removal of basement back-ups and rer ewal of neighborhood
confidence in areas where these have occurred.
5. Provision of recreation areas close-at—hand requiring minimum
energy expenditure.
6. A management system providing for the maximum in public
participation and response.
The 208 program could be expected to result in the following social
problems or costs:
1. Difficult land-use control problems along trunk sewer lines trav-
ersing areas that should remain in agriculture.
-------
V-70
2. A possible increase in land use controls such as minimum lot areas
for septic tank use that will be difficult to enforce.
3. Lateral sewer systems in certain outlying communities and in
certain unincorporated areas that will be extremely expensive on a
per-family basis and that would require financial assistance to an
extent greater than that previously provided.
4. A management system requiring a greater awareness of’ areawide
needs and approaches than may be possible to attain.
Economic and Social Impacts of Alternate Plans
Economic Impacts
The annual costs of areawide plans varied from a low of $11,719,000 to
a high of $12,353,000, a difference of only 5.4 percent, probably less than the
probability of error in such preliminary estimates of plus or minus ten
percent. Generally the economic impacts can be considered to be the same.
The variability in economic impacts will depend much more on the
methods of financing chosen. For example, if general bonds can be issued and
retired from user charges, substantial savings would be made. In the ICA
area particularly, the consolidation of effort and financing into a single area-
wide agency would smooth out disparities and provide the advantage of a
larger unit issuing bonds in larger amounts.
If any of the “Family I” group of management alternatives is used to
manage the 208 program, there will be varied economic impacts in different
parts of the 208 area. The “Family F’ group provide an areawide agency that
is charged with planning, programming, priority setting and coordination. It
would do no construction or operation. Under such an arrangement, there
-------
V-7 1
would be difficulties in financing some of the improvements called for in the
plans.
However, the economic and other problems cited above would be
identical for all alternatives.
Social Impact
Variations in social impact are likely to result more from the
management than from the facility alternatives. The proposed management
plan would provide an areawide agency that would represent the 26 cities and
counties, all of which would participate in its government. This unique
arrangement would foster participation of local officials and, through them,
participation of the public.
If the areawide agency is created as a sewer district under Chapter 358
of the Iowa statutes, it would be governed by an elected board of three and
such a board might not be so responsive to the individual communities or to
the public.
If the areawide agency does only the planning, priority setting and
coordination leaving the financing to the individual communities or various
combinations of them, it is possible to envision long periods of delay as the
financing of each project is worked out. A more powerful areawide agency
would be better able to carry out the plan.
-------
VI-1
CHAPTER VI- ADVERSE IMPACTS WHICH CANNOT BE
AVOIDED SHOULD THE PLAN BE IMPLEMENTED AND
STEPS TO MINIMIZE HARM TO THE ENVIRONMENT
Air Quality Impacts
The Intensity Development Plan adopted by the 208 Policy Committee
will continue the trend of expansion of the urbanized area and thereby
continue the trend of increasing use of private automobiles. This will have an
adverse effect on air quality (primarily carbon monoxide) in some parts of the
denser urbanized areas, particularly under atmospheric conditions which
disperse pollutants slowly.
The success of current air quality maintenance plans will rest heavily on
the success of auto manufacturers in building low-emission engines without
increasing fuel consumption. Other means of minimizing harm would be to
increase car pooling, to place certain restrictions on private cars on traffic
thoroughfares well served by public transportation or to expand the scope of
public transportation throughout the metropolitan area.
Impact on Land and Land Use
Approximately 200 acres of land (much of it agricultural land though
not all Class I and II) will be required in outlying communities for
construction and expansion of wastewater treatment lagoons. Based on
recent agricultural statistics in the area, it would be reasonable to expect
those 200 acres to produce approximately 8,000 bushels of corfl per year,
2,000 bushels of soybeans per year, 500 bushels of oats per year with
approximately 50 acres remaining for pasture and other crops.
Approximately 25,000 acres of cropland will be used over the next 20
years for urban development, according to the Intensity Development
-------
VI-2
Pattern. This land could produce 1,260,000 bushels of corn per year, 285,000
bushels of soybeans per year and 56,000 bushels of oats per year.
To minimize the impact of these land takings on agricultural produc-
tion, lagoons and urban development should be located wherever possible on
land that is marginal in productivity.
Disruption by Sewer Alignments
Semi-natural Floodplain Habitats
Temporary disruption of vegetation and wildlife habitats would result
from construction and placement of sewer pipes along approximately 2-1/2
miles of the lower Beaver Creek; approximately 3-1/2 miles of the Des
Moines River near the northern City limits; approximately 12 miles along the
Lower Fourmile Creek and approximately nine miles along the Lower East
Branch of Fourmile Creek. Excavation for placement and covering of the
sewer pipes would result in the loss of shrubs aiid trees for much of these
distances as well as herbaceous vegetation which provides cover for many
birds, rabbits, squirrels and amphibians.
Steps required to minimize harm include cutting the minimum necessary
swath of vegetation for trenching and pipe placement; final alignments which
minimize the taking of intermediate and mature trees; filling and regrading
of backfill material as quickly as possible after trenching; special provisions
to ensure that the final cover material over trenched areas is soil equal in
quality to the topsoil removed during excavation; replanting excavated areas
with materials that are native to the disturbed areas or otherwise well suited
to it; provision for several post-construction inspections to identify and
remedy areas where special erosion control and/or replanting are advisable.
Urban-Suburban Areas
Approximately four miles of pipe construction are required through the
urban center of Des Moines along the Des Moines River; approximately 9-1/2
-------
VI-3
miles downstream of the urban center along the Des Moines; and approxi-
mately 10-1/2 miles along Yeader Creek and Middle Creek. These alignments
will interrupt traffic and other urban activities to varying degrees depending
on exact location; they will be disruptive because of construction noise; and
they may generate substantial amounts of fugitive dust during construction,
depending on weather and soil moisture conditions.
To minimize harm in these settings, it will be necessary to plan
adequate auto and pedestrian traffic re-routing in advance for each
excavation step along the alignment; special traffic signaling and/or police
patrol may be required; protective shields may be required in certain areas to
minimize safety hazards to pedestrians; and in the event of high dust
generation, spraying earth mounds with water may be required from time to
time.
Within urban and suburban areas there are also more localized pockets
of trees and mixed vegetation which provide scenic relief and some wildlife
benefit. Wherever possible, alignments should be selected which minimize
the taking of trees and severing of semi-natural areas of vegetation. Where
taking of such areas is inevitable, all steps described above for semi-natural
floodplain habitats should be followed.
Construction of Facilities over Surf icial Aquifers and Floodplain Areas
Much of the sewer alignment along the Des Moines River and Fourmile
Creek would lie over surficial aquifers (where substantial groundwater
recharge takes place) and in floodprone land areas. The new treatment plant
would also lie over a surf icial aquifer, and part if not all would be reached by
the 100-year flood level.
To minimize the potential environmental hazard of these placements,
all materials used for sewer construction should meet the strictest reasonable
specifications for material strength, quality of joint welds, reliability of
-------
VI-4
pumps at lift stations including back-up systems, and stability of earth
materials used in securing the placement of the pipes underground.
Protective dykes should be used around the treatment plant to at least meet
the 100-year recurrence flood level. Test wells should be used in the vicinity
of the treatment plant to monitor groundwater quality on a regular basis
after the plant is operating.
-------
vu-i
CHAPTER VII - RELATIONSHIP BETWEEN LOCAL SHORT-TERM
USES OF MAN’S ENVIRONMENT AND THE MAINTENANCE OF
LONG-TERM PRODUCTIVITY
In this discussion, “local short-term uses” of the environment means
uses of land, water, air and other natural resources (including those required
for generation of necessary electrical and mechanical power) to collect, treat
and dispose of wastewater in the Des Moines 208 study area and those
resources required to prevent or minimize the impact of rural and urban non-
point sources of water pollution in the study area. “Long-term productivity”
means the on-going, more or less stable operation of the natural and man-
modif led ecosystems which make up the study area, namely river ecosystems,
agricultural ecosystems, conserved natural ecosystems (such as upland and
lowland terrestrial forests, lakes and wetlands) and the urban ecosystem.
More detailed descriptions of each ecosystem type were developed in an
earlier phase of this study.
The long-term productivity of all river ecosystems and all wetland
ecosystems in the study area depend critically on reaching the water quality
goals set forth in the first phase of this study. Fish, the food and breeding
grounds they depend on, and aquatic organisms that mineralize organic waste
products all require levels of water quality not achievable without the
improvements in wastewater treatment recommended here. Uncontrolled
runoff from agricultural lands and feedlots would eventually overburden the
capacity of nearly all streams and rivers to assimilate the waste products and
nutrient and sediment loadings received. The proposed plan would protect
water quality in the study area from further degradation and in many cases
allow slow, steady improvement in water quality, thereby improving condi-
tions for aquatic animals and the stability of the ecosystem of which they are
a part.
-------
VII-2
Long-term productivity of the agricultural ecosystem depends on
conservation of soil fertility, which requires runoff control to hold soil
moisture and applied organic and inorganic fertilizer supplements. It also
requires protection of groundwater quality for outlying residents using
shallow wells as sources of potable water. In addition, cost-effective
methods of soil tillage and protection of soil fertility are important in view of
rising fertilizer, fuel and machinery costs. Long-term objectives should
include maximum use of agricultural and other organic wastes for soil
conditioning and maintenance of fertility, tillage methods which minimize the
number of machine trips over cultivated lands per growing season, and the
maximum use of vegetation buffers and other non-structural techniques for
conservation of soil water in well-drained areas.
The conserved natural ecosystems require protection from other uses
except those consistent with the conservation management objectives and the
water-related ecosystems depend on good water quality in the same way river
ecosystems do. They harbor most of what remains of wildlife populations,
they protect water quality in many cases by allowing efficient natural
recharge of groundwater; they protect air quality by direct assimilation of
certain pollutants and by decreasing local densities of air-polluting land uses;
they aid in noise abatement in the same way as in air pollution abatement and
they provide visual and aesthetic relief from a sometimes monotonous
landscape.
Long-term productivity of the urban ecosystem relates most critically
to the short—term uses discussed here in that it requires a safe, reliable and
affordable source of potable water to support a growing number of people.
This component of the urban ecosystem is particularly sensitive to the quality
of storm runoff from rural and urban surfaces. While effective treatment
methods are available for minimizing hazards associated with pathogenic
bacteria, dissolved minerals and suspended particles, adequate protection
against viruses and stable organic compounds less easily filtered or
precipitated is less sure. The first line of defense in potable water
procurement is a watershed which generates a minimum of hazardous
compounds.
-------
VIII-’
CHAPTER VIII - IRREVERSIBLE AND IRRETRIEVABLE
COMMITMENTS OF RESOURCES RESULTING FROM THE PLAN
Land and energy (primarily electrical) are the two greatest areas of
resource commitment resulting from the plan. Facility plans for outlying
areas will require approximately 200 acres for construction of new and
enlargement of existing waste treatment lagoons. Between 35 and 40 acres
of urban land are required for construction of the equalization basins
throughout the urbanized area designed to prevent sewer back-ups during
storm flows. Approximately 5-10 acres will be required for flow separators.
A strip of land roughly 50 miles in length and 50-1 50 feet in width depending
on pipe size and specific land form will be excavated for placement of sewer
pipes. The new areawide treatment plant will require approximately 70 acres
of land now zoned for industrial use.
The land commitment having the greatest long-term impact is the
agricultural land required in outlying areas for waste treatment lagoons.
Wherever possible agricultural takings should be minimized in the siting of
these lagoons.
Total estimates of energy required per year to operate all transport and
treatment facilities are in the range of 17 million kilowatt-hours per year of
electrical energy, roughly 30,000 gallons of fuel to operate sludge-hauling
trucks and approximately 130,000 gallons of fuel oil or its equivalent to heat
buildings associated with the areawide treatment facility.
Disposable supplies required for treatment plant operation are primarily
chlorine (roughly 300 tons per year) and polymers to aid coagulation and
settling (roughly 250 tons per year).
-------
LC-1
LITERATURE CITED
Avcin, M. 1975. Personal Communication, July 15, 1975. Iowa Geological
Survey, Iowa City.
Baumann, E.R. and J. DeBoer. 1972. Pre-impoundment Water Quality Study,
3aylorville Reservoir, Des Moines River, Iowa. Engineering Research
Institute, Iowa State University, Ames, Iowa.
Beum& in, E.R. and S. Kelman. 1970. Pre-impoundment Water Quality Study,
Saylorville Reservoir, Des Moines River, Iow i, August 1, 1964, to
July 31, 1970. Engineering Research Institute, Iowa State University,
Ames, Iowa.
Baumann, E.R. and C. Oulman. 1973. Water Quality Studies - Red Rock and
Saylorville Reservoirs, Des Moines, Iowa. Engineering Research
Institute, Iowa State University, Ames, Iowa.
Belirose, Frank C. 1968. Waterfowl Migration Corridors East of the Rocky
Mountains in the United States. illinois Natural History Survey
Biological Notes, No. 61.
Braun, E. Lucy. 1950. Deciduous Forests of Eastern North America. The
Blakiston Company, Philadelphia, Pennsylvania.
Cargo and Mallory. 1974. Seismic Risk Zones .
Central Iowa Regional Association of Local Governments. 1974. The Des
Moines Urbanized Area Transportation Air Quality Report for 1974.
CIRALG, Des Moines, Iowa.
Central Iowa Regional Association of Local Governments. 1976a. Des
Moines 208 Areawide Waste Treatment Management Plan Phase 1
Interim Report, January 19, 1976. CIRALG, Des Moines, Iowa.
Central Iowa Regional Association of Local Governments. 1976b. Des
Moines 208 Areawide Waste Treatment Management Plan Phase 2
Interim Report, November, 1976. CIRALG, Des Moines, Iowa.
Central Iowa Regional Association of Local Governments. 1977. Des Moines
208 Areawide Waste Treatment Management Plan Phase 3 Interim
Report, February, 1977. CIRALG, Des Moines, Iowa.
Curtis, John T. 1959. The Vegetation of Wisconsin. The University of
Wisconsin Press, Madison, Wisconsin.
-------
LC-2
Des Moines Plan and Zoning Commission. 1976. 1990/200 Public Park and
Open Space Plan. Des Moines Plan and Zoning Commission, Des Moines,
Iowa.
Dorheim, F.H. 1970. Mineral Resources Map of Iowa. Iowa Geological
Survey (1:500,000 scale).
Dorheim, F.H. 1975. Personal Communication, July 15, 1975. Iowa
Geological Survey, Iowa City.
Fernald, M.L. 1950. (editor). Gray’s Manual of Botany , Eighth Edition.
American Book Company, New York.
Gradwohi, David M. 1974. Archaeology of the Central Des Moines River
Valley: A Preliminary Survey. Aspects of Upper Great Lakes
Anthropology, Minnesota Historical Society, St. Paul.
Haars, Dr. Ellen. 1976. Personal Communication, February 23 and 24, 1976.
(Iowa DEQ).
Iowa Conservation Commission. 1972. Outdoor Recreation in Iowa. Iowa
Conservation Commission, Des Moines, Iowa.
Iowa Crop and Livestock Reporting Service. 1975. Acreage and Production
Reports. USDA and Iowa Department of Agriculture, Des Moines, Iowa.
Iowa Department of Environmental Quality. 1973. (Air Quality Management
Division). Iowa Air Quality Report. Iowa DEQ, Des Moines, Iowa.
Iowa Department of Environmental Quality. 1975a. Iowa Water Quality
Report. Iowa DEQ, Des Moines, Iowa.
Iowa Department of Environmental Quality. 1975b. Water Quality
Management Plan, Des Moines River Basin, Part II. Planning and
Analysis Section, Iowa DEQ, Des Moines, Iowa.
Iowa Department of Environmental Quality. 1975c. Des Moines River Basin
Plan. Iowa DEQ, In press.
Iowa Department of Environmental Quality. 1975d. Water Quality
Management Plan - Des Moines River Basin, Part I. Planning and
Analysis Section, Iowa DEQ, Des Moines, Iowa.
Iowa Natural Resources Council. 1953. An Inventory of Water Resources and
Water Problems, Des Moines River Basin. Bulletin No. 1.
Iowa (State) Department of Health. 1934. Report on the Investigations of
Pollution of the Des Moines River from Estherville to Farmington,
1928-1934. State Department of Health, Des Moines, Iowa.
-------
LC-3
Iowa (State) Hygienic Laboratory. 1970. Water Quality Survey of the Des
Moines River, Des Moines, Iowa Area. Laboratory Report No. 71-13,
University of Iowa, Iowa City, Iowa.
Iowa (State) Hygienic Laboratory. 1974. Des Moines River (Fort Dodge to
Des Moines). Laboratory Report No. 74-19. University of Iowa, Iowa
City, Iowa.
Johnson, D. 1976. Personal Communication, April 26, 1976. Des Moines
Water Works.
Kilkus, Stephen P., J.D. LaPerriere, and R. W. Bachmann. 1975. Nutrients
and Algae in Some Central Iowa Streams. J. of the WPCFed 47(7):
18 70—79.
Moss, R. 1975. Personal Communication, July 21, 1975. (City of Des Moines
and Polk County Air Pollution Control Board, Des Moines, Iowa.)
Real Estate Research Corporation. 1973. Economic and Market Analysis of
Des Moines, Volume II: City and Metropolitan Area Trends and
Projections. Real Estate Research Corp., Chicago, Illinois.
Sales and Marketing Management. 1976. 1976 Survey of Buying Power (in
two parts). SMM, New York.
Spencer. 1972. The Dynamics of the Earth.
The Editor and Publisher Co. 1976. 1976 Editor and Publisher Market Guide.
The Editor and Publisher Co., Inc., New York.
Twenter, F.R., and R.W. Coble. 1965. The Water Story in Central Iowa.
Iowa Geological Survey Water Atlas, No. 1, Iowa Geological Survey.
U.S. Army Engineer District (Rock Island). 1975. Draft Environmental
Impact Statement, Red Rock Dam and Lake Red Rock. U.S. Army
Engineer District, Rock Island, Illinois.
U.S. Army Engineer district (Rock Island). 1975. Effects of Alternative
Release Rates from Saylorville Dam. Prepared for the U.S. Army
Engineer District Rock Island, Corps of Engineers by Roy F. Weston,
Inc., Wilmette, Illinois.
U.S. Army Engineering Division (Rock Island). March, 1974. Saylorville Lake
Flood Control Project, Des Moines River, Iowa. Final Environmental
Statement.
Upper Mississippi River Comprehensive Basin Study Coordinating Committee.
1970. UMRCBS, Volumes III and IV.
-------
APPENDIX A
-------
A—i
Table A-la
CHARACTERISTICS OF COMPONENT SOILS IN GENERAL
SOIL AREA # 1
Silty Clay
Clarion Loam Nicollet Loam Webster Loam
Color Dark Brown Dark Brown Dark Brown
Parent Material: Glacial Till Glacial Till Glacial Till &
Sediments
Native Veg.: Prairie Prairie Prairie
Typical Slope (%): 2—9 1-3 0-2
Landscape Posi- Upland Upland Inter- Upland Flats &
tion: mediate Highs Swales
Drainage Class: Well Drained Somewhat Poorly Poorly Drained
Drained
Permeability: Moderate Moderate Moderately Slow
to Moderate
Depth to Water
Table (feet): ) 5 2-4 1-3
Available Water
Capacity: High High High
Flooding Poten- Produces Run- Produces Slow Produces Slow
tial: off Runoff Runoff
Corn Suitability
Rating (max.): 87 90 85
Soil Loss Factors
(T,K): 4,0.32 4,0.32
-------
A-2
Table A-i b
CHARACTERISTICS OF COMPONENT SOILS IN GENERAL
SOIL AREA # 2
Hayden Loam Lester Loam
Color: Light Moderately Dark
Parent Material: Glacial Till Glacial Till
Native Veg.: Forest Prairie and Forest
Typical Slope (%): 2-25 2—25
Landscape Position: Upland Ridges & Upland Ridges &
Side Slopes Side Slopes
Drainage Class: Well Drained Well Drained
Permeability: Moderate Moderate
Depth to Water Rable (feet): > 5 >5
Available Water Capacity: High High
Flooding Potential: Produces Runoff Produces Runoff
Corn Suitability Rating
(Max.): 72 77
Soil Loss Factors (T,K): 4,0.37 4,0.32
-------
A-3
Table A-ic
CHARACTERISTICS OF COMPONENT SOILS IN GENERAL
SOIL AREA # 3
Dickinson
Cob Silty Waukegan Fine Sandy Dorchester
Clay Loam Silt Loam Loam Silt Loam
Color: Dark Dark Dark Light to Mod-
erately Dark
Parent Material: Alluvium Silty Allu- Dominantly Calcareous
vium over Aeolian Alluvium
Sand with Sand
Little Gravel
Native Veg.: Prairie Prairie Prairie Grass & Scat-
tered Trees
Typical Slope
(%): 0—2 1-5 2-9 0-1
Landscape P0- First Bot- Downstream Uplands & Bottomland
tomland, Terrace & Stream
Foot- Glacial Terraces
slopes Outwash
Plains
Drainage Class: Poorly Well Drained Somewhat Well to Moder-
Drained Excessive- ately Well
ly Drained Drained
Permeability: Moderate- Moderate Moderately Moderate
Slow (Upper 24- Rapid
40”), Ra-
pid Below
Depth to Water Generally
Table (feet): 1—3 > 5 >10 Below S
Available Water
Capacity: High Moderate Low High
Flooding Poten- Subject to Produces Produces Frequent Floods
tial: Standing Runoff Runoff of Short
Water Duration
Corn Suitability
Rating (Max. ): 80 73 60 85
Soil Loss Fac-
tors (T, K): 3,0.32
-------
A-4
Table A-id
CHARACTERISTICS OF COMPONENT SOILS IN GENERAL
SOIL AREA # 4
Fayette Silt Loam Downs Silt Loam
Color: Light Moderate-dark
Parent Material: Loess Loess
Native Veg.: Forest Prairie and Forest
Typical Slope (%): 2-5 2—5
Landscape Position: Upland ridges and Upland ridges and
sideslopes sideslopes
Drainage Class: Well drained Well drained
Permeability: Moderate Moderate
Depth to Water Table
(feet): > 5 >5
Available Water
Capacity: High High
Flooding Potential: Produces runoff Produces runoff
Corn Suitability
Rating (Max.): 85 90
Soil Loss Factors
(T,K): 4,0.37 4,0.32
-------
A-5
Table A-i e
CHARACTERISTICS OF COMPONENT SOILS IN GENERAL
SOIL AREA # 4a
Ladoga Silt Loam Lindley Loam
Color: Moderate-dark Light
Parent Material: Loess Loamy Glacial Till
Native Veg.: Prairie-forest Forest
Typical Slope (%): 2-5 14-25
Landscape Position: Convex upland rid- Dissected uplands,
ges and sideslopes sideslopes and nar-
and stream benches row ridgetops
Drainage Class: Moderate- well Moderate-well
drained drained
Permeability: Moderate-slow Moderate-slow
Depth to Water Table
(feet): > 5 >5
Available Water
Capacity: High High
Flooding Potential: Produces medium Produces rapid
runoff; bench runoff
phases receive
surface water from
higher areas
Corn Suitability
Rating (max.): 85 50
Soil Loss Factors
(T,K): 4,0.37 3,0.43
-------
A-6
Table A-if
CHARACTERISTICS OF COMPONENT SOILS IN GENERAL
SOIL AREA # 5
Muscatine Silty
Tama Silty Clay Loam Clay Loam
Color: Dark Brown (yellow- Dark
brown subst.)
Parent Material: Loess Loess
Native Veg.: Prairie Prairie
Typical Slope (%): 2-9 1-3
Landscape Position: Upland Ridges and Upland Ridges and
Sideslopes some Footsiopes
Drainage Class: Well Drained Somewhat Poorly
Drained
Permeability: Moderate Moderate
Depth to Water
Table (feet): > 5 2-4
Available Water
Capacity: High High
Flooding Potential: Produces Runoff Produces Runoff,
Low Spots may Pond
Corn Suitability
Rating (max.): 95 100
Soil Loss Factors
(T,K): 5,0.32 5,0.32
-------
A-?
Table A-lg
CHARACTERISTICS OF COMPONENT SOILS IN GENERAL
SOIL AREA # 5a
Sharpsburg Silty
Clay Loam Shelby Loam
Color: Dark Dark
Parent Material: Loess Glacial Till
Native Veg.: Prairie Prairie
Typical Slope (%): 2-9 9-18
Landscape Position: Upland divides, Upland sideslopes
convex ridgetops and narrow
and sideslopes ridgetops
Drainage Class: Moderately Well Well to Moderately
Drained Well Drained
Permeability: Moderate-slow Moderate-slow
Depth to Water
Table (feet): > 5 5-10
Available Water
Capacity: High High
Flooding Potential: Produces medium Produces rapid
to rapid runoff runoff
Corn Suitability
Rating (max.): 92 60
Soil Loss Factors
(T ,K): 4,0.37 4,0.37
-------
A-8
Table A-lh
CHARACTERISTICS OF COMPONENT SOILS IN GENERAL
SOIL AREA # 6
Sparta Loamy Farrar Fine Chelsea Loamy
Fine Sand Sandy Loam Fine Sand
Color: Moderate-dark Dark Brown Dark Grey-brons
brown (yellow subs.)
Parent Material: Aeolian Sands Aeolian Aeolian Sands
Sands Over
Glacial Till
Native Veg.: Prairie Forest
Typical Slope (%): 3-14 5-20
Landscape Po- Upland Stream Upland Stream
sition: Terrace Terrace
Drainage Class: Excessively Somewhat Excessively
Drained Excessively Drained
Drained
Permeability Very Rapid Rapid
Depth to Water
Table (feet): > 10 >5 >10
Available Water
Capacity Very Low Very Low
Flooding P0- Produces Produces
tential: Runoff Runoff
Corn Suitability
Rating (max.): 45 41
Soil Loss Factors
(T, K): 5,0.17 5,0.17
-------
A-9
Table A-2
INTERIM LIST 9F ENDANGERED SPECIES - IOWA
Vascular Plants
Latin Binomial Family Common Name
*Aconjtum novaboracense Ranunculaceae Monkshood
Agastache foeniculum Labiatae None
Allium cernuum Liliaceae Nodding wild onion
Amorpha nana Leguminosae Fragrant false indigo
Arctostaphylos uva-ursi Ericaceae Bearberry
Asciepias languinosa Asclepiaeaceae None
*Asclepias meadii Asclepiacaceae Meadts milkweed
Asciepias auriculata Asclepiacaceae None
Astragalus striatus Leguminosae None
Bidens beckii Compositae Water marigold
Botrychium multifidum Ophioglossiaceae Leather grape fern
Botrychium simplex Ophioglossiaceae Least grape ferm
Buchloe dactyloides Gramineae Buffalo grass
Brasenia schreberi Nympheaceae Water shield
Carex aggregata Cyperaceae None
Carex crawfordii Cyperaceae None
Carex leptalea Cypefàceae None
Carex media Cyperaceae None
Carex saximontana Cyperaceae None
Carex tonsa Cyperaceae None
Cerastium arvense Caryophyllaceae Field chickweed
Chimaphila umbellata Ericaceae Princ&s pine
Chrysosplenium ioense Saxifragaceae Golden saxifrage
Cornus canadensis Cornaceae Dwarf cornel
Corydalis aruea Papavaraceae None
Cristatella jamesii Capparidaceae None
Cypripedium candidum Orchidaceae Small white ladyslipper
Cypripedium reginae Orchidaeeae Shown lady-slipper
Decodon verticillata Lythraceae Water willow
Drosera rotundifolia Droseraceae Sundew
Dryopteris marginalis Aspleniaceae Marginal shield fern
Dryopteris intermedia Aspleniaceae
Elatine triandra Elatinaceae None
Eleocharis eoloradoensis Cyperaceae None
Eleocharis atropurpurea Cyperaceae None
Equisetum scirpoides Equisetaceae Dwarf scouring rush
E. sylvaticum Equisetaceae
E. pratense Equisetaceae None
Eriophorum angustifolium Cyperaceae Bog cotton
*Federal ‘endangered’ (proposed) list
-------
A-i 0
Table A-2 (Continued) -
E. gracile Cyperaceae Slender cotton grass
Fimbristylis autumnalis Cyperaceae None
Gerardia gattingeri Scrophulariaceae None
Gerardia skinneriana Scrophulariaeeae None
Habenaria flava var. herbiola Orehidaceae Pale green orchid
Heteranthera limosa Pontederiacea
Hudsonia tomentosa Cistaceae Poverty grass
Hybanthus concolor Violaceae Green violet
Hypericum boreale Hypericaceae St. John’s wort
-flex verticillata Aquifoliaceae Winterberry
Jeffersonia diphylla Berberidaceae Twin-leaf
Juncus alpinus Juncaceae None
Juncus greenii Juncaceae
Justicia americana Acanthaceae Water-willow
Leehea intermedia Cistaeeae
*Lespedeza leptostachya Leguminosae Prairie bush clover
Linnaea borealis Caprifoliaceae Twinflower
Lycopodium clavatum Lycopodiaceae
Lycopodium flabelliforme Lycopodiaceae
Lycopodium porophillium Lycopodiaceae
Menyanthes trifoliata Menyanthaceae Bog buckbean
Mertensia paniculata Boraginaceae Northern lungwort
Mitchella reperis Rubiaceae partridge berry
Myriophyllum pinnatum Haloragaceae
Ophioglossum pseudopodum Ophioglossiaceae Adder’s tongue fern
Oryzopsis pungens Gramineae
Osmunda cinnamomea Osmundaceae Cinnamon fern
Osmunda regalis Osmundaceae Royal fern
Panicum linearifolium Gramineae
Peltranara virginica Araceae Arrow arum
Petalostemum viliosum Leguminsoae Silky prairie clover
Polygala incarnata Polygalaceae
P. polygame Polyga laceae
Poa languida Gramineae
Proserpinaca palustris Halogragaeeae mermaid weed
Pyrola secunda Ericaceae Shinleaf
Rhexia virginica melastomataceae Meadow beauty
Ribes hudsonianum Saxifragaceae
Salix lucida Salicaceae Shining willow
Salix pedicellaris Salicaceae Bog willow
Schedonnardus paniculatus Gramineae
Scirpus paludosus Cyperaceae
Talinum parviflorum Portulacaceae Fame flower
T. rugospermum Portulacaceae
Utricula gibba Lentibualriaceae
U. minor Lentibualriaceae
*Federal ‘endangered’ (proposed) list
-------
A-il
Table A-2 (Continued)
Vaccinum angustifolium Ericaceae Low sweet blueberry
V. myrtilloices Ericaceae Velvel-leaf blueberry
Vailisneria americana Hydrocharitaceae Tapegrass
Veronica americana Scrophulariaceae
Woodsia oregana Aspleniaceae Western cliff fern
W. ilvinsis Aspleniaceae Rusty cliff fern
Birds
Common Name
Red-shouldered Hawk Buteo lineatus
Marsh Hawk (Harrier) Circus cyaneus
Piping Plover Charadrius melodus
Upland Sandpiper Bartramia longicauda
Barn Owl Tyto alba
Least Tern Sterna albifrons
Mammals
Common Name
Pygmy shrew
*Indjana Bat
Plains Pocket Mouse
Grasshopper Mouse
Red-backed Vole
Woodland Vole
Ermine (short-tailed weasel)
Bobcat
Reptiles and Amphibians
Common Name
Illinois mud turtle
Wood turtle
Great plains skink
Western Slender Glass Lizard
Speckled Kingsnake
Northern Copperhead
Prairie Rattlesnake
Central Newt
*}? ederal tendangered? (proposed) list
-------
A tfl
i-I i 1.
Table A-2 (Continued)
Fish
Common Name
Pallid sturgeon
Lake chub
Blacknose Shiner
Pearl Dace
Black Redhorse
Plains Topminnow
Longear Sunfish
Orangethroat Darter
------- |