DRAFT
ENVIRONMENTAL IMPACT STATEMENT
NORTH FULTON COUNTY, GEORGIA
WPC-GA. 189
and
NORTHEAST COBB COUNTY, GEORGIA
WPC-GA. 173
ENVIRONMENTAL PROTECTION AGENCY
1411 PEACHY*
ATLANTA.
July 6, 1973
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ENVIRONMENTAL PROTECTION AGENCY
REGION IV
1421 Psachtrea St.. N.E., Atlanta, Georgia 30309
July 6, 1973
Mr. Paul DeFalco, Jr.
Environmemtal Protection Agency, Region IX
100 California Street
San Francisco, Cal. 94111
Dear Mr. DeFalco:
Enclosed is the draft environmental impact statement on
North Fulton County, Georgia, WPC-Ga. 189, and Northeast
Cobb County, Georgia, WPC-Ga. 173.
Any comments you may have on this statement should be sent
within 30 days of the date of this letter to
Sheppard N. Moore
Chief, EIS Branch
Environmental Protection Agency
Region IV
1421 Peachtree Street, N. E.
Atlanta, Georgia 30309
A public hearing will be held on this draft EIS at the
Roswell High School, 1331 Alpharetta Road, Roswell, Georgia
on July 21, 1973. The hearing will begin at 10:00 a.m. with
registration opening at 9:00 a.m. Those persons wishing to
address EPA will be called upon to speak in the order of
registration.
Sincerely,
Regional Administrator
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NOTICE OF PUBLIC HEARING
You arc hereby notified that a public hearing will be held at
10:00 a.m. on July 21, 1973 at the Roswell High School, 1331 Alpharetta
Road, Roswell, Georgia. This will be a public hearing to present and
recc-Lvc comments on the Draft Environmental Impact Statement, North
KulI on Comity, Georgia. The proposed action consists of major expansions
Lo an existing sewerage system. The hearing is being conducted jointly
by the
Environmental Protection Division
Georgia Department of Natural Resources
47 Trinity Avenue, S. W.
Atlanta, Georgia 30334
Telephone: 404/656-4713
and
U. S. Environmental Protection Agency
Region IV
1421 Peachtree Street, N. E.
Atlanta, Georgia 30309
Telephone: 404/526-5415
The hearing will be called to order at 10:00 a.m. and will continue
until those persons who have registered to speak have been heard. A
Registration Desk will be set up at the hearing room and any person who
wishes to present a statement shall be required to personally enter his or
her name in the registration book provided for that purpose. Persons may
begin to register at 9:00 a.m. All persons will be called to speak in the
order in which they have registered.
1.
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Anyone may present data, make a statement, or offer a viewpoint
or .irnumi-iiL ciLlier or:iliy or in writing. Lenytliy statements containing
considerable technical or economic data shall be submitted in writing
for the official record. Oral statements should be concise to permit
everyone an opportunity to be heard. Hearing participants will not
be subject to questioning from the audience but may be questioned by
the hearing officer for clarification of technical points or to develop
better understanding of statements. The hearing will be recorded and
transcribed by an official court reporter and the record of the hearing
will be included in the final environmental impact statement. Statements,
supplements to statements, or briefs, may be submitted within 15 calendar
days following the date of the hearing. Such information should be
mailed to:
Sheppard N. Moore, Chief
Environmental Impact Statements Staff
U. S. Environmental Protection Agency
1421 Peachtree Street, N. E.
Atlanta, Georgia 30309
The North Fulton County project file is available for inspection
by any interested party at the Georgia Department of Natural Resources,
Environmental Protection Division offices, Room 609, State Health
Building, 47 Trinity Avenue, Atlanta, Georgia.
The draft environmental impact statement shall serve as an
outline for discussion. Copies of this draft are also available for
inspection at the following locations during office hours:
Environmental Protection Agency
Region IV
1421 Feachtree St., N. E.
Atlanta, Georgia (Phone: 526-5415)
2.
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Office of the Clerk to Commission
Mr. Frank Fling
Fulton County Administration Building - Room 407
165 Central Avenue, S. W.
Atlanta, Georgia 30303 (572-2791)
Office of the Director of Public Works
Fulton County Administration Building - Room 300
165 Central Avenue, S. W.
Atlanta, Georgia 30303 (572-2271)
ALpliaretta Public Library
15 Academy Street
Alpharetta, Georgia (475-6821)
Sandy Springs Public Library
395 Mt. Vernon Highway
Sandy Springs, Georgia (255-4085)
Smith Memorial Library
973 Alpharetta Road
Roswell, Georgia (993-6511)
To be published July 1, 1973 and July 15, 1973.
3.
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DRAFT
ENVIRONMENTAL IMPACT STATEMENT
NORTH FULTON COUNTY, GEORGIA
WPC-Ga. 189
and
NORTHEAST COBB COUNTY, GEORGIA
WPC-Ga. 173
Environmental Protection Agency
Region IV
1421 Peachtree Street, N. E.
Atlanta, Georgia 30309
July 6, 1973
Approved by:
:gional Administrator Date
July 2. 1973
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TABLE OF CONTENTS
CHAPTER PAGE NO.
Introduction 1
I Summary 5
II Background 9
A. Projects Covered by This EIS 9
B. Drainage Basins 9
C. General Description of The Area 11
D. Existing Water Supply and Sewerage Facilities 13
E. Activities of Federal, State, and Local
Government Agencies 18
F. Population Projections 29
III Alternatives 31
General 31
Present Constraints to Alternatives 31
Alternative No. 1 - No Action 34
Alternative No. 2 - Projects as Proposed 36
A. Proposed Projects Which Have Received
Grant Offers Under WPC-Ga-189 36
B. Projects Which Have Received Grant 40
Offers Under WPC-Ga-173
C. Projects Proposed for Future Funding 42
Alternative No. 3 - A Sewage Treatment Plant for 44
Alpharetta
Alternative No. 4 - A Sewer Design for 1990 Versus a 46
Design for the Ultimate Population
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TABLE OF CONTENTS (Continued)
CHAPTER PAGE NO.
IV Environmental Effects of The Proposed Projects 48
I. Adverse Effects 48
A. Construction 48
B. Effects of Sewerage Facilities 50
C. The Effects of Urban Runoff In North Fulton County 55
D. Buffer Zones 65
II. Beneficial Effects 66
A. Water Quality 66
B. Summary 70
V Relationships Between Local Short-Term Use of the 71
Environment and Long-Term Maintenance or Enhancement
of the Environment
VI Comments 73
APPENDIX
A. Urban Runoff Computations - A Simplified Fortran IV 74
Program and Procedure for Developing Contaminant
Concentrations and Flood Water Quantities for
Specific Rainfall Events
ii
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LIST OF FIGURES
No. Page No.
1 North Fulton County Area 9a
2 Drainage Basins - North Fulton County Area 9b
3 Planning Areas 1971 - North Fulton County 25
4 Existing and Proposed Projects
North Fulton and Northeast Cobb Counties 38
5 Drainage Pattern Core Area of Alpharetta 49
LIST OF TABLES
I Land Use Changes - Five County Metro Area 21
II Riverbank Land Use 21
III Summary of Preliminary Operational Plan 26
January 1971
IV Big Creek WPCP 1980 Service 35
V Estimated Cost - Alternative No. 2 - Projects
as Proposed 43a
iii
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DRAFT
ENVIRONMENTAL IMPACT STATEMENT
NORTH FULTON COUNTY, GEORGIA
WPC-Ga. 189
and
NORTHEAST COBB COUNTY, GEORGIA
WPC-Ga. 173
INTRODUCTION
This Draft Environmental Impact Statement (EIS) has been
prepared pursuant to the National Environmental Policy Act
(NEPA) of 1969 which directs the responsible Federal agency to
develop EIS's in accordance with guidelines set forth by the
President's Council on Environmental Quality (CEQ) on all major
actions which have a significant impact on the quality of the
human environment.
For purposes of this Environmental Impact Statement,
EPA, Region IV, Atlanta, Georgia, is the "Responsible Federal
Agency" as required by NEPA.
To insure that the public is kept fully informed regarding
this action, and that it participates to the fullest extent in
the agency's decision making process, this Draft EIS is being
circulated for a 45-day review as required by the CEQ guidelines
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published in the Federal Register dated May 2, 1973.
In addition, Federal, State and local agencies with
collateral interests in, special expertise, or jurisdiction
by law, are being solicited for formal comment to aid EPA in
its decision making.
This EIS is based on currently available data and
information and does not dictate the ultimate solution to
water quality management for the area. Pollution abatement
and precaution is an ongoing endeavor where State and local
government have prime responsibility.
However, irrespective of prevailing statutory and
regulatory actions and imposition on treatment and disposal
of municipal wastewater, NEPA mandates a full disclosure of
all reasonable alternatives and their suspected, anticipated,
and otherwise identifiable environmental impacts. Necessarily,
alternative actions which may mitigate adverse primary or
secondary impacts discussed in this EIS may fall outside the
implicit regulatory and enforcement authority of the EPA.
EPA, Region IV, published on December 14, 1972, a
Negative Declaration and Environmental Appraisal on the Big
Creek Water Pollution Control Facility which is a part of
the sewerage system for which funds will be available pending
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compliance with NEPA. This action has allowed the applicant to
proceed with construction of that facility to meet a pressing
water pollution abatement need.
This Impact Statement addresses a proposed plan for
providing collection and treatment of domestic sewage in parts
of north Fulton County and northeast Cobb County, Georgia and
possible alternatives to that plan. The main question is this:
Given the fact that north Fulton County and northeast Cobb
County are going to develop residentially and commercially,
what is the best method for collecting and treating domestic
sewage? Although the secondary effects of development are
discussed, EPA does not have the authority to limit land
development or dictate the type of land development. The
discussion of secondary effects (primarily storm runoff) is
presented so that State and local government can make plans
for minimizing the future environmental impacts of urban
development.
This Environmental Impact Statement covers projects which
are proposed for (1) additional sewering of the approximate
middle third of the 87,000 acres of north Fulton County, (2)
a contiguous area of 10,900 acres in Cobb County, and (3)
sewers for areas south of the Chattahoochee River (north
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Fulton County being north of the river), including approximately
2,800 acres in the River Ridge area and approximately 1,700 acres
in DeKalb County.
These projects which include interceptor sewers, pump
stations, and force mains, are components of a plan by Fulton
County to sewer all of north Fulton County, contiguous areas,
and the River Ridge area. Also included are two interceptors
to be constructed by Cobb County.
The sewerage facilities discussed in this statement
either have been awarded grant funds under WPC-Ga. 189, Fulton
County, WPC-Ga. 173, Cobb County, or are proposed for future
funding. Authorization by EPA to proceed with construction
of the sewerage projects will not be made until a minimum of
30 days has elapsed from the log date of filing of the Final
EIS with the President's Council on Environmental Quality.
Grant funds released thereupon will be applied to the projects
as approved and/or modified in the Final EIS.
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CHAPTER I
SUMMARY
(X) DRAFT ENVIRONMENTAL IMPACT STATEMENT
( ) FINAL ENVIRONMENTAL IMPACT STATEMENT
Environmental Protection Agency, Region IV, Atlanta, Georgia
1. Name of Action
Administrative Action (X)
Legislative Action ( )
2. The proposed action consists of expansions to an existing
sewerage system. Some of the projects have been awarded a grant
under the existing project numbers WPC-Ga.-189, Fulton County,
and WPC-Ga.-173, Cobb County; funding of the remaining projects
are proposed as future grant applications.
The projects which have been awarded grant funds consist of
(1) interceptor sewers and (2) pumping stations and force mains
for river crossings. Projects proposed for funding consists
of interceptor sewers and expansions to the existing Big Creek
sewage treatment plant in north Fulton County.
The present system in north Fulton County consists of
interceptor sewers, collection lines and a 1.1 mgd secondary
treatment plant utilizing the activated sludge process. A con-
tract has been awarded for construction of an initial 6.0 mgd
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module to be built as needed.
3. The beneficial effect of the proposed action is the protec-
tion of public health and welfare. Sanitary sewage will be
treated by modern wastewater collection and treatment techniques
prior to discharge to the Chattahoochee River, which is used
for public water supply and extensive water-based recreation.
The sewerage program will help protect the high water quality
of the Chattahoochee River, upstream of Atlanta, Georgia that
would be affected by wastewater discharges from the project area.
This will (1) protect the river's aesthetic and recreational
values; (2) help it to meet its present classification of "drink-
ing water supply," upstream of Atlanta; (3) protect the water
quality of the tributaries to the river so that the standards
for the classification of "fish and wildlife" may be met [the
1972 Amendments of the Federal Water Pollution Control Act (FWPCA)
require a minimum stream classification of "fish and wildlife"];
and (4) prevent further degradation of the Chattahoochee River
below Atlanta due to the potential sewage flow from the north
Fulton County and Cobb County area.
The primary adverse consequence of the proposed action
is the stimulation of the "secondary effects" caused by urban
development. The effects are: (1) urban runoff and stream
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pollution, (2) soil erosion and sedimentation, and (3) reduction
of the aesthetic values of the Chattahoochee River corridor.
The effects of development on water quality are only poorly
understood. However, modeling efforts in this EIS show that
degradation will occur and that the slug effect of runoff from
man-made impervious surfaces could cause a temporary violation
of water quality standards in the Chattahoochee River and
adjacent streams.
Other adverse effects which will result are those related
to actual construction of the facilities. These include removal
of vegetation, short-term erosion and siltation, noise, dust,
and inconvenience to some area residents.
It should be understood that the areas covered by these
projects are going to develop with or without a regional sewer
system unless State or local governments implement stricter
land use controls and constraints. Numerous examples both
within Georgia and elsewhere in EPA, Region IV indicate that
similar urban areas have developed without a regional sewer system
through the use of septic tanks, lagoons, and small factory-made
sewage treatment plants. The funded projects will eliminate the
use and need of lagoons, package plants and septic tanks in the
affected areas.
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4. Alternatives considered are:
Alternative No. 1 - No Action
Alternative No. 2 - Projects as Proposed
Alternative No. 3 - A Sewage Treatment Plant for Alpharetta
Alternative No, 4 - A Sewer Design for 1990 Versus a Design
for the Ultimate Population
5. The following U. S. Senators and U. S. Representatives,
Federal, State and local agencies, have been requested to comment
on this Draft:
U. S. SENATORS
Honorable Herman Talmadge Honorable Sam Nunn
U. S. Senate U. S. Senate
347 Old Senate Office Building 3331 Senate Office Building
Washington, D. C. 20510 Washington, D. C. 20510
U. S. REPRESENTATIVES
Mr. Andrew Young Mr. John W. Davis
1533 Longworth House Office Building 1728 Longworth Office Building
Washington, D. C. 20515 Washington, D. C. 20515
Mr. Ben Blackburn
1024 Longworth House Office Building
Washington, D. C. 20515
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STATE AGENCIES
Honorable Jimmy Carter
Governor of the State of Georgia
State Capitol
Atlanta, Georgia 30334
Mr. R. S. Howard, Jr., Director
Environmental Protection Division
Department of Natural Resources
47 Trinity Avenue, S. W.
Atlanta, Georgia 30334
Mr. James T. Mclntyre, Jr., Director
Office of Planning & Budget
270 Washington Street, S. W.
Room 611
Atlanta, Georgia 30334
FEDERAL AGENCIES
Mr. Charles Bartlett
State Conservationist
Soil Conservation Service
P. 0. Box 832
Athens, Georgia 30601
Mr. Bruce Blanchard
Environmental Project Review
Office of the Secretary
U. S. Department of the Interior
Washington, D. C. 20240
Mr. Pat Choate, Regional Director
Economic Development Administration
1401 Peachtree Street, N. E.
Atlanta, Georgia 30309
Mr. Herbert F. DeSimone
Assistant Secretary for Environment
and Urban Systems
Department of Transportation
Washington, D. C. 20590
Mr. Edward H. Baxter
Regional Administrator
Department of Housing and
Urban Development
50 7th Street, N. E.
Atlanta, Georgia 30323
Mr. Herschel Bryant
Division Engineer
Federal Highway Administration
900 Peachtree Street, N. E.
Atlanta, Georgia 30309
Commander
Seventh Coast Guard District
1018 Federal Building
51 Southwest First Avenue
Miami, Florida 33130
Division Engineer
South Atlantic Division
U. S. Corps of Engineers
Title Building, 30 Pryor St., S.
Atlanta, Georgia 30303
W.
8a
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Dr. Merlin D. DuVal
Assistant Secretary for
Health and Science Affairs
Department of Health, Education
and Welfare
North Building
Washington, D. C. 20202
Mr. Frank J. Groschelle, Regional
Director, Department of Health
Education and Welfare
50 7th Street, N. E.
Atlanta, Georgia 30323
National Oceanographic and
Atmospheric Administration
6000 Executive Boulevard
Rockville, Mayland 20850
Mr. T. A. Schlapfer, Regional Forester
U. S. Forest Service
1720 Peachtree Road
Atlanta, Georgia 30309
LOCAL AGENCIES
Mr. Harry West, Director
Atlanta Regional Commission
910 Equitable Building
Atlanta, Georgia 30303
Mr. Robert L. Sutton, Jr.
County Engineer
Cobb County Engineering Dept.
P. 0. Box 649
Marietta, Georgia 30060
Mr. Bud Cameron
DeKalb Water and Sewer Department
P. 0. Box 1087
Decatur, Georgia 30030
Mr. Kenneth E. Grant,
Administrator, Soil Conservation
Service
U. S. Department of Agriculture
Washington, D. C. 20250
Mr. Maurice Kinslow
Regional Director
Food and Drug Administration
60 8th Street, N. E.
Atlanta, Georgia 30309
Col. J. B. Newman
Executive Director of Civil Works
Office of the Chief of Engineers
U. S. Corps of Engineers
Washington, D. C. 20314
Colonel Howard L. Strohecker
District Engineer
Savannah District
U. S. Corps of Engineers
P. 0. Box 889
Savannah, Georgia 31402
Mr. Howard Frandsen
Assistant Director of
Public Works and Chief Engineer
Fulton County
Room 300
Fulton County Administration Bldg.
165 Central Avenue, S. W.
Atlanta, Georgia 30303
8b
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6. This Statement was made available to the Council on Environmental
Quality and the Public on July 6, 1973.
8c
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CHAPTER II
BACKGROUND
A. Projects Covered by This EIS
The subject projects are part of a proposed sewerage
system for all of the north Fulton County area which includes
(1) all of north Fulton County, (2) the Sandy Springs area,
(3) a portion of northwest DeKalb County, and (4) northeast
Cobb County. This Environmental Impact Statement covers
proposed projects which would be an extension of existing
facilities constructed under WPC-Ga. 189, Fulton County, and
WPC-Ga. 173, Cobb County, and are in the area tributary to the
existing Big Creek Sewage Treatment Plant or in the Sandy
Springs area; these areas are shown in Figures 1 and 2.
B. Drainage Basins
The north Fulton County area is divided into two major
drainage basins. The northern part of the area drains into
the Etowah River, while the southern part drains into the
Chattahoochee River Basin. The applicable sub-basins, which
are tributaries to the Big Creek Treatment Plant or to Cobb
County's Chattahoochee River Treatment Plant, are listed below
and shown in Figure 2.
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/*•
^ ',
o° J
NORTH FULTON. COUNTY
DEKALB COUMTV
LIMITS
CHATTAHOOC HEE
RIVER STP(&OBB COUNTY)
FI6.1
NORTH FULTON COUNTY AREA
9a
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s
SUB-BASINS
1. Willeo Creek (Fulton and Cobb Counties)
2. Chattahoochee I
3. Foe Killer
It. Big Creek
5. Ball Mill Creek (Fulton and OeKalb)
6. Chattahoochee II West
Boundary of Potential Service Area
of the Big Creek Treatment Plant
Potential Service Areas for
Cobb County's Treatment Plant
8. Huntcliff
9. River Ridge
3.0. Parkai're (Cobb County)
LEGEND
County Limits
Sub-Basin Limits
\G CREEPS
FIGURE 2
DRAINAGE BASINS
NORTH FULTON COUNTY AREA
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Big Creek sub-basins Sandy Springs sub-basin Parkaire sub-basin
(Cobb County)
Willeo Creek River Ridge
(Fulton and
Cobb Counties)
Chattahoochee I
Foe Killer Creek
Big Creek
Chattahoochee II West
Ball Mill Creek
(Fulton and DeKalb Counties)
Roberts Drive
Huntcliff
In addition to their Fulton County acreage, Ball Mill and
Willeo Creek sub-basins receive flow from contiguous areas
located in Cobb and DeKalb Counties, respectively. Since the
natural drainage is through Fulton County, sewage from these
contiguous areas was considered in the proposed sewage treatment
plan.
There are two incorporated municipalities in the Big Creek
sub-basin: Alpharetta and Roswell. The Sandy Springs area
is unincorporated.
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C. General Description of The Area
Land; Eighty-five to ninety percent of the total area is
presently in agricultural and forestry uses. The agricultural
land is used for dairy, livestock, poultry, and row crop
farming. Some of the timber land is used for pulp wooding with
pine as the main species. The forested area along the streams
produces a wide variety of hardwood species, i.e. oak, hickory,
birch, poplar, etc. Much of the flood-plain area has been
in cultivation at some time. The majority of the land is
characterized by gently rolling hills with elevations ranging
from 800 feet along the river in the River Ridge area to
1,280 feet near the Cherokee County line.
The rainfall is abundant, averaging about 52 inches per
year. As a consequence of this rainfall, annual runoff is
approximately 16 inches.
The Chattahooch.ee River: The Chattahoochee River is the
dominant water course of the north Fulton area. It has widths
of 150 to 200 feet with a river bed width averaging 60 feet.
Average flow of the river is 2,500 cfs (cubic feet per second),
with a record drought flow of 350 cfs. The water quality in
the north Fulton County area is rated high with dissolved
oxygen being approximately 7 mg/1 (milligrams per liter) and
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fecal coliform counts rarely exceeding 1000/100 ml (milliliters)
at the Atlanta water supply intake.
The rivet begins in the North Georgia mountains, becomes
a main lake (Lake Lanier, formed by Buford Dam) northeast of
Fulton County, flows in a southwesterly direction forming the
southern boundary of north Fulton County and eventually finds
its way into the Gulf of Mexico.
A stretch of the river with considerable aesthetic
attraction and high water quality is from Buford Dam downstream
for a distance of 48 miles where it enters the Atlanta region
and water quality drastically deteriorates. This 48-mile
stretch of the river and adjacent land, known as the Chattahoochee
River Corridor, is characterized by rapids and lazy waters,
sheer cliffs, rock outcrops, and undisturbed forested hills.
Major uses of the river along the corridor are water
supply and recreation. The counties of Gwinnett, DeKalb, Cobb
and Fulton (Fulton County acquires water from Atlanta) and the
City of Atlanta obtain raw water from the Chattahoochee within
the corridor.
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D. Existing Water Supply and Sewerage Facilities
Water Supply Facilities; There are three sources of
water for the homes in the north Fulton County area: the
north Fulton County water system, the Roswell water system,
and private wells. The north Fulton County system consists
of approximately eighty-five miles of water main. Water for
this system,which is distributed throughout the county, is
purchased by Fulton County from the city of Atlanta. Atlanta
owns and operates its treatment facilities and draws water
from the Chattahooch.ee River. The Roswell water system con-
sists of a treatment plant, which receives water from Big
Creek, and a distribution system which serves the city of
Roswell and a portion of the county in the Roswell vicinity.
The north Fulton County and the Roswell systems provide a
basis to serve approximately eighty-five percent (85%) of
the Bounty. Homes in the unincorporated areas not using
either of the two systems described above rely on individual or
small group wells.
The city of Alpharetta has a water distribution system
while purchasing its water requirements from Fulton County.
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Roswell's Water Supply; Roswell treats approximately
700,000 gpd (gallons per day) of raw water while purchasing
approximately 100,000—200,000 gpd from Fulton County.
Recommendations from the consultant for Roswell for meeting
future needs include: (1) increasing the capacity of its
present water treatment plant, (2) constructing a new plant,
(3) buying water from Fulton or Cobb County, (4) formation
of a joint authority which would include representatives
from Roswell, Alpharetta, and unincorporated areas of Fulton
County. These recommendations could result in continued use
of Big Creek or use of the Chattahoochee River as a source of
raw water. Sewage treatment plant locations upstream of
Roswell's present water supply intake could have some effect on
this water supply resulting in a need for a high degree of
sewage treatment. This effect will not occur if Roswell decides
to draw its water from the Chattahoochee River above the mouth
of Big Creek.
Sewerage Facilities; The existing sewerage facilities are
shown in Figure 4. The Big Creek interceptor sewer, which
discharges into the Big Creek water pollution control plant,
runs along the Chattahoochee River to Big Creek, and then along
Big Creek north of Hoicomb Bridge Road. The two pumping stations
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located at the end of the Big Creek interceptor sewer lift
the sewage into the treatment plant. A trunk sewer extends
north up Hog Wallow Creek on the east side of Roswell.
An additional trunk sewer extends from the Big Creek
sewer running in an easterly direction, parallel to the
Chattahoochee River serving the Martin's Landing area and
homes along Riverside Drive. The Roberts Drive interceptor
is located on the south side of the river, extending from the
North Fulton Expressway to Roswell Road, the point at which
the sewage is pumped to the sewer on the north side of the
river.
Roswell has completed Phase I of its collection system
which serves basically the east side of the city via the
existing 24-inch interceptor sewer which extends from the
existing Big Creek Treatment Plant along the river, up
Big Creek to Holcomb Bridge Road. Construction of Phase II, to
service the west side of Roswell has been planned.
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The existing 1.1 mgd (million gallons per day) activated
sludge Big Creek Treatment Plant is the only major treatment
facility in the north Fulton County area. The plant site
consists of approximately 40 acres bounded on the north by
Roswell-Marietta Road and on the west by Willeo Creek. The
property is densely wooded around its perimeter and inter-
mittently throughout largely by mature pine trees. The
existing and proposed water pollution control plant site is,
for the most part, in the low, flat, cleared land abutting
the creek. The nearest proposed structure to the Roswell-
Marietta Road site is at a distance of 600 feet, and blocked
from view from the road by trees and hills.
Willeo Creek, into which the existing sewage treatment
plant effluent discharges, flows perennially to the Chattahoochee
River. It varies in width from 15 to 40 feet with clay bottom
and meanders through a low, scrubby swamp area for about a
mile, where it meets Little Willeo Creek and Willeo Road,
and continues a few hundred feet to the Chattahoochee River.
The Environmental Protection Agency has approved a
grant, plans, and specifications for an addition to the
existing Big Creek Treatment Plant. The addition, for which
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a negative declaration was written and a contract awarded,
will increase the capacity of the plant by 6.0 mgd. The plant
will utilize the activated sludge process and will include, (1)
an outfall line direct to the Chattahoochee River, (2) a
diffuser at the end of the outfall line, and (3) dual
chlorination facilities.
Incident to this expansion will be the modification of
a lift station at Willeo Road and the Chattahoochee River to
increase the peaking capacity of the existing main trunk sewer
entering the plant at 8 mgd. This will not require additional
pipe capacity.
Upon completion of the 6 mgd expansion, the existing
1.1 mgd plant and 6 mgd expansion will operate as two facilities.
If the effluent from the existing and proposed treatment
plant is discharged to Willeo Creek, there would be a real
possibility of nutrient buildup in the lower reaches of the
Creek. Consequently the effluent will be combined for
chlorination and discharged through the outfall line and a
diffuser to the Chattahoochee River, a distance of approximately
5,000 feet.
Sludge from the combined 7.1 mgd treatment facility will
be dried in sludge drying beds and disposed of at the county
sanitary landfill.
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E. Activities of Federal, State, and Local Government Agencies
The uses of the Chattahoochee River are many, ranging from
recreational to commercial. It serves as a source of freshwater
supply for numerous communities, the greatest user being the
Atlanta metropolitan area. Above this area the River is used
for recreational purposes as well as a source of drinking water.
Immediately below this area the water quality is degraded
as it receives sewage, storm water runoff, and industrial
pollutants, and carries these downstream. However, farther
downriver the use once again is raw water supply for the
city of LaGrange.
During the Enforcement Conference on the Chattahoochee,
the charge was established that one entity will not have to
pay the environmental costs incurred by another, the emphasis
being on point sources of pollution such as sewerage treatment
plants and industrial discharges.
In conformity with the principles set forth at the
Enforcement Conference, north Fulton County must do its share
in maintaining the quality of the Chattahoochee River as the
area urbanizes. Activities at various levels of government
are briefly discussed in the following pages to bring atten-
tion to those actions designed to protect the quality of the
18
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Chattahoochee River and adjacent land in the North Fulton
County area.
Atlanta Regional Commission (ARC) . Section 2 of Act 5,
Georgia Laws 1971, created the Atlanta Regional Commission
(ARC) to provide policy direction for the solution of common
problems through short-and long-range comprehensive planning.
In planning for the Atlanta area, ARC has made a study of the
Chattahoochee River Corrider and published the results in a
report entitled the Chattahoochee Corridor Study. The report includes
a comprehensive land use plan with development standards and
recommended acquisition of public lands.
The basic objective of the plan is to minimize the adverse
impact of urban development on the Chattahoochee Corridor by
reducing the potential for urban runoff, erosion, and siltation.
The plan recommends public purchase of approximately 6,000 acres
of park land and open space. The sites range from islands of
less than one acre to a major park containing almost 2,200
acres and stretching six miles along the Chattahoochee in
Gwinnett and Forsyth Counties.
The development standards are divided into two areas:
countywide recommendations and recommendations for the
river corridor which pertain to the land within 2,000 feet
19
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on either side of the river. The countywide recommendations
for soil erosion, sediment control, and land development plans
are given because some pollutants from outside the Corridor
eventually find their way into the river. Development standards
for the Corridor include general standards and standards for
river buffer, flood hazard, and voluntary protection zones.
Bureau of Outdoor Recreation (BOR) In April 1972, the
Bureau of Outdoor Recreation completed a study and analysis
of the Chattahoochee River and adjacent lands beginning at
Buford Dam and ending 48 miles downstream. The results were
put in a report entitled Chattahoochee Recreation Study Area.
The report presents a concept plan with two objectives: provision
for public outdoor recreation use of the river and protection of
the unique values and quality of the river environment. A land
use plan along the Chattahoochee River Corridor with recommendations
for acquisition, development, and implementation is included in
the report.
The land use plan provides needed public parks, recreation,
and open spaces to balance urban development and population growth.
During the past five years, Metropolitan Atlanta has grown and
changed substantially. From 1961 to 1967, about 90 square miles
of vacant and rural land were developed for various urban purposes.
20
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Table I (helow)
shows trends in land use for the five-
county metropolitan region.
TABLE
Land Use
Rural or vacant
Residential
Industrial
Other—Urban
i/
LAND-USE CHANGES
FIVE COUNTY METRO AREA
Square Miles
1961
1,424
147
23
130
1967
1,288
244
30
162
1968
892
467
56
309
\J Atlanta Regional Metropolitan
Planning Commission, 1970
Change in land use has started in the Chattahoochee Corridor.
Riverbank land use is shown in Table II (below) for the 48 miles
TABLE II
on each bank.
Use
Open Space
Residential
Apartment
Commerical
Public
Private—Other
_!/ Less than one percent
2_f Do not total because of rounding
Miles
75.59
9.20
.01
7.98
1.67
1.74
96.19
Percent of Total
78
9
I/
8
2
2
21
21
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The shortage of developed recreational lands in the
Atlanta metropolitan area in 1969 was nearly 16,000 acres;
up from 10,000 acres in 1960 (based on a minimum standard
of 18 acres per 1,000 population). The BOR plan provides for
open space and recreatonal areas to reduce the recreational
lands shortage and provides protection of the unique value
and quality of the river environment.
In its initial stages the BOR study was part of a nation-
wide program for developing several national parks in or near
large urban areas. As such, massive Federal funding or
assistance was being considered. The price tag for implementing
the recommendations of the Draft Chattahoochee Recreation Study
Area is 85 million dollars. However, the BOR has now reversed
itself and withdrawn the previous recommendation for Federal
funding and turned the plan over to local government for State
and local implementation and financing. This action has
essentially left the original BOR draft report as simply a
"good idea" with little realistic hope for full implementation.
Fulton County Department of Planning. The Fulton County
Department of Planning prepared a preliminary Operational Plan
(January, 1971) for north Fulton County. North Fulton was
divided into three planning areas (shown in Figure 3):
22
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Hopewell, State Bridge, and Holcomb. A summary of the
Operational Plan is given below and in Table III. Statistics
within the corporate limits of Roswell and Alpharetta were
excluded.
Hopewell: Contains only four percent of the unincorporated
population of north Fulton County. All the residential units
are single family. The Hopewell planning area is designated
as the "secondary development area" of north Fulton, where
development will be characterized as low density of a rural
nature with 0—1.0 units per acre.
State Bridge; Three percent of the land area has been designated
"diversified activities" in the Operational Plan. This land
lies on either side of the North Fulton Expressway and is for
use of apartments, shopping centers, etc. The 1970 population
of this area was 246 percent greater than the 1960 population,
while Alpharetta1s population approximately doubled from 1,349
to 2,455. The Alpharetta growth was probably due to annexation,
700 acres have been annexed since 1965. At present (January 1971)
there are no multiple family homes outside the city limits.
In the future, approximately 50 percent of the construction
will be for multiple family units.
23
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Holcomb; Only one percent of this area had been rezoned from
AG-1 up to 1960. By September 1970, this figure had increased
to 9 percent; one-half of this increase is due to zoning for
the Martin's Landing area. All apartment zoning has occurred
since January 1970; this being in the Roswell community. In
the future, 50 percent of the construction will be for multiple
family units. The operational plan for the Holcomb area pro-
poses the use of 1,500 acres for a Chattahoochee River front.
No intense recreational development was considered. However,
the plan expressed that it is hoped the natural scenic beauty
of the Chattahoochee may be retained available for public use.
2A
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PLANNING AREAS AND COMMUNITIES
NORTHERN FULTON COUNTY, GEORGIA
LEGEND
Planning Area
Hope well
1 IIIMINGtUM
2 THOMMON
i IIITL'I iivu
4 (HHfFU
State Bridge
I umimt
7 OCIl
} IIUUIIG
4 MfDtOCK
Holcomb
I GIlfNWAT
I lOSWdl
3 H(W TOWN
E1G. 3
25
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TABLE III
Summary of Preliminary Operational Plan, January 1971
Fulton County Department of Planning
Present Projected Total Percent
„, _. * *>~n.,i af-i^n Pnnu i a f i nn Acres Rezoned Maior Land Use (%)
nuuuiuft Aiea Population Pnp,,l«rinn From AG-1 Afi-1 Sine.Fam. Others
Hopewelli/ 3,253 1978 25,000 - 0 - 95 4
3,840
1988
Mai or Proposed Land Use
Sing.Fam. Multi.Fam. Others
(See discussion on the
Hopewell planning area)
5,750
State Bridge!/ 3,600 1980 35,000 1 94 2 2
127800 (Parks &
Recreation)
M 1990
28,000
Holcomb 5,000 1980 23,000 9 93 5
30,000
1990
91 - 0 - 5
(Parks ,
Recreation £
Open Space)
3
(Diversified
Activities)
86 2 8
(Park, Re-
creation &
Open Space)
62,000
I/ Statistical information for the planning area excludes all land within the
~~ city of Roswell's corporate limits.
2/ Statistical information for the planning area excludes all land within the
~~ city of Alpharetta's corporate limits.
-------
Metropolitan River Protection Act; This Act, passed
by the 1973 General Assembly of the State of Georgia, is
applicable to the Chattahoochee River corridor (all land
within 2,000 feet of the River from Buford Dam to Peachtree
Creek). The purpose of the Act is to require special regula-
tions for development within the Corridor for protection of
public water supplies. Also, the purpose of the Act is to
provide a method whereby certain political subdivisions may
utilize the police power of the State in protecting public
water supplies and preventing floods and flood damage, to
control erosion, siltation, and density of development. A
land and water use plan, with regulations, will be prepared
by the metropolitan area planning and development commission;
for the Atlanta SMSA, this is the ARC.
Pending adoption of the plan as to each political
subdivision, it shall be unlawful for any persons to erect,
maintain, deposit, clear or excavate, so as to adversely
affect the efficiency or capacity of the water-course or
floodplain, or increase runoff, erosion or water pollution.
After adoption of the plan or any portion thereof, the
actions by persons are unlawful if they are inconsistent
or incompatible with the plan or any portions thereof.
27
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Exemptions from the Act include the following:
"Any land or water use or project which, on the
effective date of this Act, is approved, pending or is
completed, actually under construction or which is zoned
for such use and where expenditures in excess of
$2,500.00 have been made in preparation for construction
in accordance with such zoning, provided, however, that the
construction of the project is actually commenced within
thirty-six (36) months of the effective date of this Act;
otherwise, a certificate for the project must be obtained
pursuant to this Act."
28
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F. Population Projections
The population projections for north Fulton County, made
by the consultants for Fulton County, were considered excessive
by some people. EPA made projections covering the area that
would.contribute flow to the Big Creek Treatment Plant. The
consultants' figures for this area were 181,278 for 1990 and
355,793 for the ultimate population. The estimates by EPA
were 152,750 for 1990 and 344,000 for the ultimate population.
These .figures being relatively close, the .consultants'
estimates are acceptable.
EPA's population projections were developed in the following
manner. In the urban portions, the population projections pre-
pared by consulting firms under contract to Roswell and
Alpharetta were used. For the non-urban portion, population
projections developed by the Fulton County Department of
Planning were used as shown in the Operational Plans, previously
discussed in Chapter II, Background. The "ultimate" population
numbers are based upon the map development plans for and by
north Fulton and Sandy Springs which distributed the non-urban
part of North Fulton County as of September 1972 among land
uses. The following population densities were used:
29
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3.5 persons/acre - single family 0-1 units/acre
9.0 persons/acre - single family 1-4 units/acre
36.0 persons/acre - multi family
Thus the "ultimate" populations assume a future develop-
ment along the lines set out in the Operational Plan (for land
use) prepared by the Fulton County Department of Planning.
In the River Ridge area, which will contribute flow to
the Morgan Falls interceptor on the west side of the Chattahoochee
River, EPA's population projection was 19,000 for year 1990 and
20,000 for the ultimate projection. The consultants1 projection
for the ultimate population was based on approximately 22
people per acre resulting in a population of 59,730. Before
a final sewer design is approved, the differences in the
population projection for the River Ridge area will have to
be reconciled.
30
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CHAPTER III
ALTERNATIVES
General
Any alternative for meeting the sewer service needs of the
areas under consideration must take into account the following
objectives as far as sewerage facilities are applicable: (1) pre-
venting violation of water quality standards and (2) protection
of public health and welfare.
The objective of minimizing "secondary effects" which
accompany the population growth of an area—due to the desire
of people to live in that area, relatively constrained development,
lack of land use planning, and construction of roads, water supply
and sewerage facilities—is a function of local government.
Present Constraints to Alternatives
Sewage Treatment; The present system of water quality
standards does not address phosphates, nitrates, viruses, heavy
metals, pesticides, and synthetic materials. In the past several
years nutrients have been recognized as a pollutant contributing
to the potential eutrophication of a body of water. Considering
the former, it is recognized by the State of Georgia and.the
Environmental Protection Agency that nutrients are a potential
problem in large impoundments on the Chattahoochee River. A case
31
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in point is depicted in a recently published joint EPA-State
study on the Jackson Lake of South River, which revealed that
the impoundment at Lake Jackson is in a state of eutrophication
due primarily to sewage and combined sewage-storm water.overflow
from the Atlanta metro area into the South River Basin.
A mathematical model of the Chattahoochee River is being
developed jointly by the State, EPA, and outside consultants.
This is a tool which can be used to predict the effects on water
quality from future projected wastewater sources being discharged
to a river. With this tool a decision on the type and degree
of treatment necessary to meet future established water quality
standards can be made.
There are dozens of advanced waste treatment techniques,
processes, and combinations thereof. Almost all of them follow
some conventional secondary process primarily because the con-
ventional treatment process has been historically proven effective
in the efficient removal of the first 85-90 percent of the
pollutants (solids, BOD, COD, coliform bacteria). It is impor-
tant to note that with removal of solids comes elimination of
some degree of nutrients, heavy metals, pesticides, and synthetic
materials which, if present in the sewage, are absorbed, adsorbed,
or otherwise adhered to solids or are themselves solid material.
32
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The difficu]ty in sewage treatment beyond the secondary
level is the removal of the remaining BOD, SS, coliform bacteria,
nutrients, and other pollutants in solution and the high costs
associated with it. The widely acclaimed Lake Tahoe tertiary
facility is simply one type of advanced waste treatment designed
fora 99 plus percent removal of BOD, SS, coliform bacteria,
and phosphates (nitrates were removed on a pilot basis—not
continuous). Capital cost of the complete treatment facility
(exclusive of collectors, outfall, and interceptor sewers) was
210 percent greater than the conventional activated sludge pro-
cess (which was the first phase of the Tahoe Facility) and 239
percent greater than the conventional activated sludge facility
for operation and maintenance.
Treatment Systems
The systems available for sewage treatment are septic tanks,
small collection and treatment systems, and a large collection
and treatment system. The use of septic tanks eliminates the
need for a collection system; however, they do not offer sufficient
protection of public health in an urban or suburban situation.
Individual family units malfunction resulting in pollution
potential. Septic tanks are not considered suitable for multi-
family units or commercial developments.
33
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Alternative No. 1 - No Action
Treatment Facilities; Table IV gives the estimated sewage
flow to the Big Creek Treatment Plant by 1980. The existing
capacity of the plant Is 1.1 mgd. The contract award has been
approved for construction of a 6.0 mgd addition to the plant.
With the estimates shown in the table, the Big Creek Treatment
Plant capacity of 7.1 mgd (the sum of 6.0 mgd and 1.1 mgd) will
slightly exceed the estimated 1980 flow. On this basis, treat-
ment capacity for all of the tributary areas is adequate through
1980. The secondary activated sludge process used at the treat-
ment plant can produce an effluent which, when discharged to the
river, will not violate the "drinking water" classification of
the Chattahoochee River.
Sewer Lines; The capacities of the existing sewer lines
carrying sewage into the Big Creek Treatment Plant are inadequate
for the 1980 population projections. To do nothing would result
in the continued use of (a) existing septic tanks, (b) oxidation
ponds by Alpharetta, and (c) existing sewer lines; also, additional
units of septic tanks and small sewage treatment plants will be
constructed as the population increases to serve subdivisions,
apartment complexes and shopping centers.
The sub-basins in this Statement, excluding River Ridge, had
a 1970 population of 25,230; the 1980 and 1990 projections, made
34
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TABLE IV
Big Creek WPCP 1980 Service*
Area
Ro swell
Roberts Drive
N. Fulton - Holcomb Br.
Ball Mill (DeKalb)
Ball Mill (Fulton)
Martin Landing
N. Fulton Expressway Strip
Alpharetta
1/2 of Remainder of
Basin
Total
Acres
1,000
600
2,000
1,655
2,000
1,400
2,000
500
12,055
23,210
Estimated
Density Population Served
People/Acre
5
10
10
6
3
3
5
A
0.5
Avg.-3.0
5,000
6,000
20,000
10,000
6,000
A, 200
10,000
2,000
6,000
69,200
Estimated
Waste Water
mgd
0.5
0.6
2.0
1.0
0.6 •
O.A
1.0
0.2
0.6
6.9
*Assuming expansion of sewer system to serve areas in DeKalb, Cobb and
additional areas in Fulton.
35
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by EPA, are 78,350 and 152,750 respectively. As these population
projections are approached, treatment by septic tanks and package
plants will result in endangerment of public health and reduction
of water quality below the established standards for the Chattahoochee
River, along the corridor and its tributaries. Odors from these
facilities, including oxidation pond, will reduce the quality
of the environment.
Alternative No. 2 - Projects as Proposed
Construction of the proposed facilities would result in one
sewage treatment plant for the area (excluding the River Ridge
and Parkaire sewage flow which would go to a Cobb Countv treatment
facility) and construction of interceptors as shown in Figure 4.
The interceptor sizing was based on the consulting engineer's
projection for the ultimate population. The individual projects
are described below.
A. Proposed Projects Which Have Recived Grant Offers Under
WPC-Ga-189
Morgan Falls Pumping Station (PS) and Force Main (FM);
These facilities, which are located downstream of Morgan Falls Dam,
will facilitate pumping sewage contributed by the Sullivan's Creek
and Pitts Road interceptors from the east bank to the west bank
of the Chattahoochee. The flow will be discharged to the Morgan
36
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Falls interceptor. The original proposal contemplated extending
the Sullivan's Creek interceptor,(previously River Ridge, Phase
I and II) downstream, paralleling the river on the east side.
The sewage would be transported to the Marsh Creek interceptor
at Marsh Creek and then into the Marsh Creek pumping station
and pumped across the river into interceptor sewers for transport
to Cobb County's Chattahoochee River Sewage Treatment Plant.
Opposition to the construction on the east side arose because
of the resulting appreciable reduction of the aesthetic and
environmental values of the east bank of the Chattahoochee. The
east bank between Morgan Falls Dam and Marsh Creek is characterized
by a narrow flood plain, and in some areas, rock cliffs that rise
40 to 50 feet vertically from the river's edge. Consequently,
construction of a large interceptor sewer would be quite destructive
to the natural terrain unless extensive tunneling were employed
during construction. The terrain of the west bank of the river in
this area (Cobb County side) is more suitable for sewer construction
since there is a wide flood plain with only limited vegetation.
This area is discussed in more detail under the project description
for the Morgan Falls Interceptor.
Sullivan's Creek Interceptor (formerly River Ridge Phase I
and II): This project consists of an interceptor extending from
37
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1
lrt-,t!
'Iff,
-^
^
l-'-Uj)
/~v4./
•f --/V? i 1ft
LsXX / ^
C ?i I
R
xv;;//
fio
1. Big Creek Relief Int. & P.S.
2. Willeo Creek Int.
\ 3. Morgan Falls P.S. & P.M.
r= 4. Sullivans Creek Int.
5. Pitts Road Int. CO
;X — ~" f, 6. Morgan Falls Int.
,/[ ' 7. Big Creek and Foe Killer Int.
^ *// \\ 8. Chattahoochee II Int.
9. Big Creek Parallel Int.
. 10. Ball Mill Creek Int., P.S. & P.M.
~^
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the planned pumping station downstream from Morgan Falls Dam,
to serve the Sullivan's Creek area of the River Ridge sub-basin.
This area is generally bordered on the south by Morgan Falls
Road, on the north by Hightower Trail, and on the east and
west by Roberts Road and the Chattahoochee River, respectively.
Big Creek Relief Interceptor and Pumping Station: A
gravity sewer and pumping station, which will collect and
carry all sewage from the Roswell Road-Chattahoochee River
intersection to the Big Creek Treatment Plant, will replace
three existing pumping stations and sections of sewer, located
in the same general area. The originally proposed size of 60
inches has been increased to 72 inches. This increase in
capacity will replace the Huntcliff sewer which was proposed
for construction on the south side of the river, and would have
received flows from the Roberts Drive and Ball Mill drainage
areas. This change was made partly because of comments on the
environmental assessment statement for construction of sewers
on the south side of the river.
Ball Mill Creek Interceptor. Pumping Station, and Force Main;
The interceptor begins in the upstream section of Ball Mill Creek,
parallels the Creek, and at the Chattahoochee River connects to
the pumping station and force main which extends across the
39
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Chattahoochee. On the north side of the river the interceptor
parallels Riverside Road, ending at Seven Branch. The section
of the interceptor on the north side of the river was originally
located on the south side ending at the now existing Roberts
Drive interceptor. Acreage along the south side of the river
includes a Baptist campground and 200 acres of land termed the
"Woodall Tract." A major portion of the tract was on the priority
list of the State Heritage Trust Committee for acquisition and
presentation by the State of Georgia. Opposition to construc-
tion of the interceptor on the south side, expressed at the
county public hearing on their environmental assessment statement,
prompted the change in sewer line location to the north side of
the Chattahoochee River.
B. Projects which have Received Grant Offers Under WPC-GA-173.
Morgan Falls Interceptor: The project consists of an inter-
ceptor to be constructed by Cobb County which will serve the sub-
basins of River Ridge and Parkaire (Cobb County). Fulton County
will utilize part of the carrying capacity of the sewer and
participate in the costs as applicable. The sewer line will be
located on the west side of the river, extending from the Morgan
Falls force main to the Sope Creek interceptor. The sewage will
be treated at the Chattahoochee River Treatment Plant of Cobb
40
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County. Use of the Morgan Falls interceptor is an alternate
to construction of an interceptor on the east side of the
Chattahoochee, ending at the existing Marsh Creek Plant which
will be abandoned in the future. At this time, the sewage
would be pumped across the river to the Sope Creek interceptor.
The east side location of the sewer was not chosen because of
the existing aesthetic and environmental value of the east bank
of the Chattahoochee.
The Morgan Falls Interceptor, which will be constructed on
the west side of, and parallel to, the Chattahoochee River, will
traverse five archeological sites. Four of these sites are
prehistoric villages, parts of which date as early as 2000 B.C.;
this information is known from evidence found on the surface.
The fifth site is a weir or fish trap for which no known methods
exist for obtaining a date of origin. Since all present evidence
comes from surface collections and no subsoil tests have been
carried out, the entire extent of archeological data potentially
endangered is unknown.
In order to avoid further controversy, delay in construction,
and to secure the scientific data and recover cultural remains
which would otherwise be destroyed, preconstruction exploration
of the five aforementioned sites will have to be conducted.
41
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Beyond the archeological considerations, there are those
factors of geology, such as sedimentary history and formation
of particular levee systems, which have never been given valid,
in-depth research that is badly needed in view of continued
impact on flood plain areas in North America. Additionally,
there exists also the possibility of gathering critical data on
ancient climatic changes, present quality of ground water
entering the river, and related fields of inquiry.
Costs of the archeological and geological exploration
would be approximately $10,000 and $3,000, respectively.
C. Projects Proposed for Future Funding
Big Creek Parallel Interceptor: The project consists of a
sewer which is an extension of the Big Creek relief interceptor
from the river to Holcomb Bridge Road; it eliminates the need to
parallel the existing sewer through the Big Creek gorge.
Big Creek and Foe Killer Interceptors: These interceptors
will serve the Big Creek and Foe Killer Basins within Fulton
County. The sewers will serve the city of Alpharetta, the
eastern half of the city of Roswell, and the development taking
place along the North Fulton Expressway.
Willeo Creek Interceptor; An interceptor to serve the Willeo
Creek basin which consists of approximately 3,500 acres in Fulton
County, and approximately 9,000 acres in Cobb County.
42
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Chattahoochee II Interceptor: This interceptor will be
constructed in two sections: Section I and Section II. Section
I, as proposed would parallel Riverside Road from the end of the
Ball Mill Creek interceptor to junction with the Big Creek
parallel interceptor. Section II would extend east from the
Ball Mill Creek pump station for a distance of approximately
6,000 feet.
Pitts Road Interceptor; This project is proposed to serve
the southern half of the River Ridge sub-basin.
Big Creek Sewage Treatment Plant Expansions; The proposal
for expansion of the treatment facilities at the Big Creek
Plant includes a second and a third increase in capacity of 6.0
mgd each (the first addition is discussed in the section,
Existing Water Supply and Sewerage Facilities). The proposal
contemplates use of the activated sludge process and would include
microscreens and phophorus removal as needed. An incinerator is
planned for treatment of waste activated sludge, with construction
being concurrent with the second 6.0 mgd expansion.
43
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TABLE V
ESTIMATED COST
Alternative No. 2 - Projects As Proposed
Contract Estimated Total
Project Cost
WPC-Ga. 189
Big Creek Relief Sewer and Pump Station $ 3,924,000
Ball Mill Creek Int., P.S. & P.M. 1,240,000
Morgan Falls P.S. & F. M. 636,000
Sullivan's Creek Int. Sewers 553,000
Total $ 5,353,000
WPC-Ga. 173
Parkaire Outfall $ 85,000
Morgan Falls Int. (Marsh Creek to Parkaire O.F.) 646,000
Morgan Falls Int. (Park Ave. O.F. to
Morgan Falls F.M.) 315.000
Total $ 1,046,000
Proposed for Future Funding
Big Creek Parallel Int. $ 949,000
Big Creek & Foe Killer Creek Int. 3,572,000
Willeo Creek Int. 1,301,000
Chattahoochee II West (Sections I & II) 651,000
Pitts Road Int. 635,000
Big Creek STP (Expansion No.s 1 & 2) 12.500.000
Total $19,608,000
43a
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Alternative No. 3 - A Sewage Treatment. Plant for Alpharetta
This alternative consists of the existing Big Creek
Treatment Plant and a second treatment facility located on
Big Creek. The existing plant would serve Roswell and sur-
rounding areas and areas along the corridor. The second treat-
ment plant would serve Alpharetta, Foe Killer Creek sub-basin,
and upstream areas of the Big Creek sub-basin.
Many arrangements of plants to serve Alpharetta can be
used due to the drainage pattern, as shown in Figure 7, by the
creeks which begin in the core area of the city and disperse
radially, ending at Foe Killer Creek or Big Creek.
A plant site "A" was originally considered because (1) it
could receive flow from Alpharetta without the use of many
pumping stations, (2) it could treat flow from the area along
the North Fulton Expressway, thus deleting the necessity for
construction of package plants in this area, and (3) if a site
were chosen relatively close to the core area of Alpharetta septic
tanks and package plants would be used in the surrounding areas.
Site "A" was eventually rejected because the Foe Killer
sub-basin would be left without sewage facilities and thus would
have to be treated at Big Creek. Site "B" was chosen to replace
site "A"; thus site ("B") would serve all of the service area of
Site "A" and the Foe Killer sub-basin.
-------
ALPHA RE TT£
wiVi'ar.
-/-T*«
Figure 5"
DRAIMASE PATTERN
CORE AREA OF ALPHARETTA
-------
An analysis of the effect of the effluent from a plant on
site "A" was conducted before site "B" was chosen; considering
the effluent discharge and available stream flow data, advanced
waste treatment of the sewage would be necessary in order to
meet the standards for a stream classification of "fish and
wildlife." Based on the same criteria, advanced waste treatment
would also be needed for a plant located on site "B".
Treatment at a plant on site "B" would cost approximately
twice the cost of treatment at the Big Creek plant. Also, land
acquisition would be required for a new plant, the water supply
of Roswell would be compromised, and any forthcoming flexibility
in treatment systems would be reduced.
45
-------
Alternative No. 4 - A Sewer Design for 1990 Versus a Design for
the Ultimate Population
This alternative would include the sewerage facilities as
proposed with the exception of designing the Big Creek Relief
Interceptor for the 1990 population projection and in 1990 cons-
tructing an additional interceptor such that the total capacity
of the interceptors will be adequate for the ultimate population.
The existing 30-inch line to the plant has a capacity of
6.35 mgd (based on a minimum acceptable velocity of two feet
per second). In order to meet the required capacity of the
1990 projection of approximately 182,000 people, a 42-inch diameter
pipe will have to be installed. In 1990, an additional pipeline
of 54-inch diameter would have to be installed assuming the
existing 30-inch line is operable. If this line is not efficiently
operable due to deterioration, a 60-inch pipeline will have to be
installed—this 60-inch pipe was assumed in making costs comparison.
In making a cost comparison of (1) installing a sewer for
1990 capacity and then adding an additional sewer in 1990 for
ultimate capacity, or (2) installing a 72-inch sewer initially,'
an interest rate of six percent was assumed. The present worth
cost of (1) would be $1,659,840.00, the cost of (2) would be
$2,122.626.00.
46
-------
This comparison does not take into account the yearly
inflationary escalation in construction costs that has been
prevalent during the last few years. Nor does this comparison
consider the increased environmental disruption and clearing
of additional trees and vegetation which will accompany the
construction of a parallel sewer at a later date. Since much
of the routing of the Big Creek relief sewer will follow an
existing roadway or traverse fields and therefore require only
limited clearing, it is recommended that the County follow
alternative No. 4 as noted in (1) above at a savings of
approximately $462,786.00. This recommendation is subject to
reconsideration if a valid economic analysis prior to cons-
truction is submitted in favor of a different alternative.
Because of the environmental concerns related to the
construction of the other interceptor sewers proposed (clearing,
siltation, noise, etc.) and significantly smaller potential
savings, the alternative of using parallel sewers (one now
and another in 1990) for providing ultimate capacity for
the other sewers included in this Impact Statement, is not
recommended. However, this alternative will be reconsidered
at such time as new grant applications are submitted for the
sewers now proposed for future funding.
47
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CHAPTER IV
ENVIRONMENTAL EFFECTS OF
THE PROPOSED PROJECTS
I. ADVERSE EFFECTS
A. Construction
The environmental areas affected by construction are listed
below.
1. Disruption of traffic.
2. Creation of the by-products of noise and dust.
3. Damage to land from erosion due to exposed soils.
4. Damage to stream banks, streams, and stream beds
due to sedimentation and siltation as consequence
of exposed soils, excavated material, and storm-
water runoff.
5. Removal of trees, vegetation, and other natural
resources.
Disruption of traffic, noise, and dust are unavoidable
consequences of construction; the only alternative being
no action. These consequences are temporary and control
measures can be utilized.
The effects of excavation, erosion, stormwater runoff,
sedimentation, and siltation can be minimized by the following
construction specifications:
48
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The constructor shall use construction techniques
to minimize erosion, siltation, and sedimentation. The
techniques will include:
• Backfilling of trenches continuously to
minimize the length of open ditch and
excavated material.
• Removal of excess excavated material to a
proper disposal area away from the streams.
• Restoration of disturbed surface areas to
their previous condition as soon as practicable.
• Use of temporary measures to prevent loss of
topsoil and direct or indirect pollution of
the streams and land through soil erosion or
sedimentation.
The removal of trees and vegetation along the right-
of-way are unavoidable and only vegetation that will allow
servicing of the sewers can be regrown. Potential damage to
trees, vegetation, and other natural resources can be reduced
by the following construction specification:
The contractor shall keep his operations within
those areas bounded by easement and necessary for
construction activity. Only those trees and other
49
-------
natural resources of the site shall be removed as
approved in the construction operations.
B. Effects of Sewerage Facilities
Treatment plants and sewers, among other public
facilities, undeniably have an effect on the natural and social
resources of an area. North Fulton County has the basic water
supply system and roads for growth; these facilities will be
complimented by the proposed sewer projects to affect the
environment in the following areas:
1. Irretrievable use of materials, through construction,
and the use of fuel by construction equipment. The
.vvjor materials are sand, cement, and steel.
2. Foreclosure of options for future land use due to
the land used by treatment facilities, with accompanying
buffer zones, and sewer line rights-of-way for the length
of the sewers.
3. Land use changes will occur through (a) rate of
land development, (b) density of development, and (c)
conversion of open spaces and aesthetic areas to
other uses.
4. Decrease in land and water quality due to erosion,
sedimentation, siltation, and urban runoff as conse-
quences of land development facilitated in part by public
facilities (water supply, roads, and sewerage facilities).
50
-------
The intensity of the effects in areas 1 and 2 cannot
be avoided. After sound engineering design and economical
construction practices have been determined, the only alterna-
tive or mitigating measure is "no action". Discussion of
areas 3 and 4 . is given in this section under the sub-headings
of Land Use Changes, Soil Erosion, and Urban Runoff.
Land Use Changes; Land use changes can have a positive
or negative effect on the environmental, social, and economical
well-being of the north Fulton County area. Calculation of
the amount of change due to sewering is most difficult to make.
Even without public sewers, given the premise that sewage
must be adequately treated, developers will provide their own
treatment facilities. Also, the desirability of the populace
to locate in a given area contributes to development. However,
an overall increase in development is consistent with sewering
and is not a largely problematic phenomenon.
Although sewering affects land use, EPA is not authorized
to determine or evaluate land use plans. The criteria of EPA's
participation is water quality demands. Mechanisms for con-
trolling land use for the public welfare and private property
rights of landowners must be provided by (1) the State of
Georgia, (2) Fulton County, and (3) the cities of Roswell and
-------
Alpharetta must provide the necessary land use controls.
Soil Erosion; A recognition of and solution to soil
erosion with resulting sedimentation and siltation is necessary
in the Fulton County area due to heavy development activity.
Sediment deposition in urban areas is as much an environmental
blight as badly paved and littered streets. Erosion reduces
home and land values as does the resulting sedimentation. Also,
sediments fill ditches and clog storm sewers, resulting in
varying degrees of flooding.
A paragraph from the ARC Corridor Study, which quantifies
soil erosion, is as follows:
"During construction when the soil is stripped of
vegetative cover, erosion presents the greatest prob-
lem. Tonnages of sediment from an acre of ground
under construction may be 20,000—40,000 times greater
than the amount eroded from farmlands over the same
period. Sediment yield is also far greater for an
urbanized than a non-urbanized basin (200—500 tons
per square mile per year on the average."
The suspended and settleable solids in a body of water
(rivers, creeks, etc.) transport other pollutants by acting
as a mobile substance to which pollutants attach themselves.
Settleable solids damage biological structures, bring organisms,
and clog respiratory organs. High suspended solids concentra-
tions reduce the transparency of water inhibiting the trans-
mission of light required for photosynthesis and interferes with
the predator-prey relationship.
52
-------
Land erosion, which is most likely to be- most severe
during urban construction, will occur during more stabilized
times. Control measures during any time of land use activity
should include soil erosion and sediment control ordinances
and regulations, administered by local governments, and field
practices during land use changes to check or minimize erosion
and to check sedimentation and siltration.
Soil erosion and sedimentation control ordinances and
regulations may include the following principles:
• Development should be fitted to topography, soils,
and vegetative cover to minimize potential erosion.
• Minimize the time of soil exposure.
• Minimize spee-J and control flow of downstream water.
• Maximize the preservation of trees and vegetation.
The standards required to realize the principles can
vary with location. The counties of Cobb and Gwinnett have
adopted ordinances and regulations for erosion control. Similar
criteria arc also given in the ARC Study.
Field practices for realization of the principles and
standards may be catagorized into two types: Mechanical and
vegetative. Mechanical practices Include: land grading,
•
bench terraces, storm sewers, lined channels, and sediment
basins. Vegetative measures include: mulching and permanent
53
-------
cover. During construction, these practices may be designed
for temporary use.
One obstacle to protecting the natural and man-made
environment from erosion and subsequent phenomena is the
generally undefinable political and institutional restraints.
Fulton County and the cities of Roswell and Alpharetta must
overcome this obstacle.
-------
-------
The amount of contaminants was derived from coefficients of Ibs/curb
mile of the various parameters measured in the Atlanta portion of the
study multiplied by the total number of curb miles projected through the
regression equation cited above. A study by Black, Crow and Eidsness,
Inc., of Atlanta, Georgia, covering storm and combined sewers provided
information on storm events intensity, duration and frequency for the
Atlanta area.
The segments to follow discuss alternatives for handling runoff
water quality problems and precautions to observe in preparing for
increased flooding potential.
Water Quality Effects
Previous studies indicate that:
• 80% of the total buildup of contaminants on street
surfaces will be complete within a 24-hour antecedent
dry period,
• 90% of contaminant washoff will occur during the first
15 minutes of the storm, and
• dissolved oxygen of the entire runoff will be at satura-
tion or above (D.0.=7.3(+) mg/1).
The Chattahoochee River is expected to be classed as a recreation stream
in 1990 with minimal discharges into it; reaeration characteristics are
good in the river upstream from this area. At the onset of a storm
event it is reasonable to project:
• a low summer flow of 1250 cfs,
• a D.O. level of 7.3(+) mg/1, and
• background BOD5 of 1.0 mg/1.
The following water quality effects are based on the runoff of the
first 15 minutes of a two-hour storm with an intensity of 0.25 inches/
hour.
Table 3 shows that for "Case 1 - Effect of Runoff of Each Area
Individually on the River" the untreated runoff for Big Creek is the
most significant, resulting in a net oxygen demand on the river of
4.4 mg/1. The projected "Net River D.O." values are hypothetical,
based on the assumptions that rainfall-runoff only results from a
single basin at a time and that the entire runoff and residual river
BOD5 would have to be satisfied by the D.O. carried by the combined
56
-------
runoff and river flow. A negligible oxygen demand on the river is
projected if standard secondary treatment (90% BOD5 removal) were
performed.
A somewhat more realistic case is the sequential inflow to the
Chattahoochee River of all eight areas grouped as shown in "Case 2"
on Table 3. The resulting oxygen demand on the river would be 5.A
mg/1. An identical demand is projected if all runoff were collected
by storm sewers and discharged at a single point.
Two impoundments located in the Big Creek and Willeo Creek areas
with capacities of 525 and 255 acre-feet would contain 80% of the total
runoff from a storm of 0.25 inches for two hours; treatment and discharge
could be accomplished over a later period of time. These impoundments
would require 25 to 50 acres each and cost approximately $100,000.00
each (based on Gwinnett County cost data for similar construction).
The retained runoff could be pumped into the proposed Big Creek plant
at slack times thereby incurring only small additional charges. An
additional benefit would be the retention of relatively high solids,
nutrients and fecal coliform concentrations along with some flood
alleviation.
Since approximately 82% of the total Chattahoochee River flow at
this time would be from this area (5863 cfs va (5863 + 1250) cfs) the
weighted average concentrations of all contaminants must be considered
for their significance to the downstream Atlanta water supply. The
cadmium concentration of 8 ppb is close to the Public Health limit for
drinking water and the lead concentration is about four times the allow-
able limit. The concentrations of contaminants in the runoff slug and
in the river after dilution by the projected low river flow are given
in Table 4.
Flooding Effects^
The development and increased population density of the total area
will cause a 17.3% increase in amount of runoff water in 1990 as compared
to 1970. This is caused by previously highly absorbent areas becoming
impervious as streets, roofs and paved parking. Individual areas vary
from a 3% increase in Willeo Creek to a 68% increase in Huntcliff. Only
three areas present possible problems:
• Big Creek (16%),
• Foe Killer (19%), and
« Willeo Creek (3%)..
57
-------
Big Creek, drainage will have to transport not only the Big Creek area
runoff but also Foe Killer runoff to the Chattahoochee River, and
Table IB indicates that by 1990 a storm event greater than the two
year recurrence interval will possibly increase considerably the
elevation of the defined flood plain perimeter as required by the
National Flood Insurance Act of 1968. A storm event with a five
year recurrence interval or greater in the Willeo Creek area could
also create flooding problems because this entire area drains only
through the single channel (also called Willeo Creek). The remaining
areas appear to offer good direct drainage into the Chattahoochee
River. The rainfall records for Fulton County indicate that storms
of greater than two hours duration tend to be less intensive than the
two hour storm and therefore have no greater flooding potential for
this particular area. Impoundments for flood alleviation only could
not be economically justified; however, flood control can add some
economic justification for the impoundments discussed in the Water
Quality Section. New flood plain designations for these three areas
should be identified and a complete ban placed on flood plain construc-
tion by strong laws. The 100 year return period flood with 1990 runoff
characteristics should be used as the reference for planning.
A procedural writeup in the appendix gives a step by step method
for calculations along with charts, tables and bibliography.
58
-------
TABLE 1A - NORMAL STORM
THE MOST FREQUENT TYPE OP ATLANTA AREA STORM HAS A RAINFALL INTENSITY
OF .25 INCHLS/HOUR AND A DIRATION TIME OF 2 HOURS
Comparative Effects
1990 vs 1970
BlR Foe Willco Chatt. Chatt. Hunt- Roberts Ball Total*
Crcok Killer Creek 1 J ^Uli Drive Mill Area
1. Acres 1970 & 1990
2. Population 1970
Copulation 1990
Population/acrt- 1970
Population/acre 1990
3. Miles of curb 1970
Miles of curb 1990
4. Impervious ac(907, RO)
Impervious ac(907, RO)
5. Total RO ac-ft 1970
Total RO ac-ft 1990
6. Rate of RO.CFS 1970
Rati' of RO.CFS 1990
22089
8100
49500
.4
2.2
93
452
70 5252
90 7126
335
389
2024
2352
7529
2600
20000
.3
2.7
30
177
1782
2559
114
136
688
824
12762
3590
7800
.3
.6
43
84
2982
3184
192
198
1160
1195
202Q
5400
31300
2.7
15.5
48
140
688
1383
37
57
221
343
3966
500
13400
.1
3.4
7
113
896
1463
59
75
355
454
TABLE IB - MAJOR STORMS (ATLANTA)
*Sce Items 1,2,3 & 4 of Table 1A for area conditions.
All storms of 2 hour duration and return period arc specified
Flooding Effects Big Foe Willco Chatt. Chatt.
1990 Crock Killer Creek 1 2
RP=2 yrs, intensity 1'Vhr
Total RO Acrc-rt. 1990
Rate of RO-CFS 1990
1555
9406
545
3297
790
4781
227
1372
300
1817
1062
1690
16750
1.6
15.8
16
74
313
732
18
30
108
181
819
250
4500
.3
5.5
3
33
192
365
12
17
75
105
as RP.
Hunt- Roberts
cliff Drive
120
725
69
419
3766
3100
9500
.8
2.5
32
85
977
1259
59
68
359
409
Ball
Hill
270
1635
54013
25230
152750
.5
2.8
272
1158
13083"
18070
825
969
4990
5863
Total*
Area
3876
23452
RP=5 yrs, intensity ].4"/lir
Total RO Acrc-tt. 1990
Rate of RO-CFS 1990
2177
13168
763
4616
1106
6894
318
1921
421
2544
168
1015
97
587
378
2289
5427
32832
RP=10yrs, intensity 1.6"/hr
Total RO Acre-Ft. 1990
Rate of RO-CFS 1990
RP=25 yrs, intensity 1.8"
Total RO Acrc-Ft. 1990
Rate of RO-CFS 1990
2488
15049
/hr
2798
16931
872
5276
981
5935
1264
7650
1423
8606
363
2195
403
2470
481
2907
541
3271
192
1159
216
1304
111
671
125
754
432
2616
486
2943
6202
37523
6977
42213
RP=50 yrs, intensity 2"/hr
Total RO Acre-Ft. 1990
Rate of RO-CFS 1990
RP=100 yrs, intensity 2.2
Total RO Acre-Ft. 1990
Rate of RO-CFS 1990
3109
18812
"/hr
3420
20693
1090
6594
1199
7254
1581
9562
1739
10519
454
2744
499
3018
601
3634
661
3998
240
1449
264
1594
139
838
152
922
540
3269
594
3596
7753
46904
8528
51594
% increase 1990 vs 1970
16
20
55
28
68
40
14
17.3
*This is a floafing point total.
59
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TABLE 2 - RUNOFF QUALITY
CONTAMINANT QUANTITIES AND CONCENTRATIONS - INITIAL 15 MINUTES
OF A NORMAL STORM EVENT OF .25 INCHES PER HOUR INTENSITY
Contaminant
BOD5, Ibs. 1970
BODs, Ibs. 1990
BOD5, mg/1 1970
BOD5, mg/1 1990
COD, Ibs. '70
COD. Ibs. '90
COD, mg/1 '70
COD, mg/1 '90
Tot. Solids, Ibs. '70
Tot. Solids. Ibs. '90
Tot. Solids, ing/1 '70
Tot. Solids, mg/1 '90
Fee. Coll.,cnt(xl010) '70
Fee. Coll.,cnt(xl010) '90
Fee. Coll.,cnt/100ml '70
Fee. Coll. ,cnt/100ml '90
Phosphates, Ibs. '70
Phosphates, Ibs. '90
Phosphates, mg/1 '70
Phosphates, mg/1 '90
Kjeldahl Nitrogen, Ibs '70
KJeldahl Nitrogen. Ibs '90
Kjeldahl Nitrogen, mg/1 '70
KJeldahl Nitrogen, mg/1 '90
Copper, Ibs. '70
Copper, Ibs. '90
Copper, mg/1 '70
Copper, mg/1 '90
Lead, Ibs '70
Lead, Ibs '90
Lead, mg/1 '70
Lead, mg/1 '90
Mercury, Ibs '70
Mercury. Ibs '90
Mercury, mg/1 '70
Mercury, mg/1 '90
Cadmium, Ibs '70
Cadmium, Ibs '90
Cadmium, mg/1 '70
Cadmium, mg/1 '90
Big
Creek
186
903
1.47
6.15
1227
5962
9.71
40.61
39973
194207
316
1323
27.0
131.0
470
1967
24
117
.19
.80
46
226
.37
1.54
6.1
29.8
.05
.20
7.2
34.8
.06
.24
2.1
10.4
.017
.071
.29
1.40
.002
.010
Foe
Killer
60
355
1.40
6.89
398
2340
9.25
45.47
12950
76235
301
1481
8.7
51.4
448
2202
8
46
.18
.90
15
89
.35
1.72
2.0
11.7
.05
.23
2.3
13.7
.05
.27
.69
4.08
.016
.079
.09
.55
.002
.011
Ullleo
Creek
86
167
1.19
2.24
568
1104
7.84
14.80
18502
35968
256
482
12.5
24.3
380
717
11
22
.15
.29
22
42
.30
.56
2.8
5.5
.04
.07
3.3
6.4
.05
.09
.99
1.92
.014
.026
.13
.26
.002
.003
Chatt.
1
96
280
6.92
13.10
631
1850
45.70
86.30
20600
60200
1490
2810
13.9
40.6
2211
4180
12
36
.90
1.70
24
70
1.73
3.27
3.2
9.2
.23
.43
3.7
10.8
.27
.50
1.10
3.22
.080
.150
.15
.43
.011
.020
Chatt.
2
15
227
.65
7.99
96
1500
4.31
52.70
3120
48700
140
1720
2.1
32.8
209
2553
2
30
.08
1.04
4
57
.16
2.00
.5
7.5
.02
.26
.6
8.7
.03
.31
.17
2.61
.007
.092
.02
.35
.001
.012
Hunt-
cliff
32
148
4.81
13.10
214
977
31.80
86.40
6970
31800
1030
2810
4.7
1.5
1539
4184
4
19
.63
1.70
8
37
1.20
3.27
1.1
4.9
.16
.43
1.3
5.7
.19
.50
.37
1.70
.055
.151
.05
.23
.007
.020
Roberts
Drive
6
67
1.27
10.20
39
441
8.37
67.50
1270
14400
273
2200
.9
9.7
406
3269
1
9
.17
1.33
1
17
.32
2.56
.2
2.2
.04
.34
.2
2.6
.05
.39
.07
.77
.015
.118
.01
.10
.002
.016
Ball
Mill
64
170
2.86
6.66
424
1120
18.90
44.00
13800
36500
616
1430
9.3
24.6
916
2130
8
22
.37
.87
16
43
.72
1.67
2.1
5.6
.09
.22
2.5
6.5
.11
.26
.74
1.95
.033
.077
.10
.26
.004
.010
Total*
Area
545
2320
1.75
6.33
3600
15300
11.50
41.80
117000
498000
376
1360
79.0
336.0
559
2023
71
301
.23
.82
136
579
.44
1.58
18.0
76.4
.06
.21
21.0
89.2
.07
.24
6.3
26.60
.020
.073
.85
3.59
.003
.010
*This is a floating point weighted total.
60
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TABLE 2 - CONTINUED
NOTE: UNITS OF CONCENTRATION'S ARE NOT UNIFORM
Big Foe Willeo Chatt. Chalt. Hunt- Roberts Ball Total*
Contaminant
Vol. Solids, Ibs. 1970
Vol. Solids, Ibs. 1990
Vol. Solids, mg/1 1970
Vol. Solids, mg/1 1990
Tot. Coli.,cnt(xl010) '70
Tot. Coli.,cnt(xl010) '90
Tot. Coll. ,cnt/100 ml '70
Tot. Coll. ,cnt/100 ml '90
Nitrates, Ibs. '70
Nitiales, Ibs. '90
Nitrates, mg/1 '70
Nitrates, mg/1 '90
Zinc, Ibs. '70
Zinc, Ihs. '90
Zinc, mg/1 '70
Zinc, ng/1 '90
Nickel, Ibs. '70
Nickel, Ibs. '90
Nickel, mg/1 '70
Nickel, mg/1 '90
Chromium, Ibs. '70
Chromium, Ibs. '90
Chromium, mg/1 '70
Chromium, mg/1 '90
Dicldrln, Ibs. '70
Dieldrin, Ibs. '90
Dleldrin, ug/1 '70
Dieldrin, ug/1 '90
PCB, Ibs. '70
PCB, Ibs. '90
PCB, ug/1 '70
PCB, ug/1 '90
DDD, Ibs. '70
DDD, Ibs. '90
DDD, ug/1 '70
DDD, ug/1 '90
P, P-DDT, Ibs '70
P, P-DDT, Ibs '90
P, P-DDT, ug/1 '70
P, P-DDT, ug/1 '90
Creek
1670
8130
13.2
55.4
297
1450
5191
21703
2.23
10.80
.018
.074
10.20
49.70
.081
.338
1.95
9.48
.016
.065
1.02
4.97
.008
.034
.0022
.0108
.0177
.0738
.0060
.0294
.0478
.2000
.0032
.0154
.0250
.1050
.0012
.0059
.0096
.0400
Killer
542
3190
12.6
62.0
96
567
4944
24303
.72
4.25
.017
.083
3.31
19.50
.077
.379
.63
3.72
.015
.072
.33
1.95
.008
.038
.0007
.0043
.0168
.0827
.0020
.0115
.0455
.2240
.0010
.0060
.0238
.1170
.0004
.0023
.0091
.0448
Creek
775
1510
10.7
20.2
138
268
4192
7907
1.03
2.01
.014
.027
4.73
9.20
.065
.123
.90
1.76
.013
.024
.47
.92
.007
.012
.0010
.0020
.0143
.0269
.0028
.0054
.0386
.0729
.0015
.0028
.0202
.0381
.0006
.0011
.0077
.0146
1
861
2520
62.3
118.0
153
448
24402
46122
1.15
3.36
.083
.157
5.26
15.40
.380
.719
1.00
2.94
.073
.137
.53
1.54
.038
.072
.0012
.0034
0830
.1570
.0031
.0091
.2250
.4250
.0016
.0048
.1180
.2220
.0006
.0018
.0450
.0850
2
130
2040
5.9
71.9
23
362
2305
28176
.17
2.72
.008
.096
.80
12.50
.036
.439
.15
2.38
.007
.084
.08
1.25
.004
.044
.0002
.0027
.0078
.0959
.0005
.0074
.0212
.2600
.0002
.0039
.0111
.1360
.0001
.0015
.0043
.0519
cliff
292
1330
43.3
118.0
52
237
16976
46163
.39
1.78
.058
.157
1.78
8.14
.265
.720
.34
1.55
.051
.137
.18
.81
.027
.072
.0004
.0018
.0578
.1570
.0011
.0048
.1560
.4250
.0006
.0025
.0818
.2220
.0002
.0010
.0313
.0851
Drive
53
602
11.4
92.0
9
107
4475
36069
.07
.80
.015
.123
.33
3.68
.070
.562
.06
.70
.013
.107
.03
.37
.007
.056
.0001
.0008
.0152
.1230
.0002
.0022
.0412
.3320
.0001
.0011
.0216
.1740
.00004
.00044
.0083
.0665
Mill
578
1530
25.8
60.0
103
272
10102
23498
.77
2.04
.034
.080
3.53
9.35
.158
.366
.68
1.78
.030
.070
.35
.94
.016
.037
.0008
.0020
.0344
.0799
.0021
.0055
.0931
.2170
.0011
.0029
.0487
.1130
.0004
.0011
.0186
.0433
Area
4900
20ROO
15 7
57.0
872
3710
6169
22324
6 54
27.80
.021
.076
30.00
127.00
.096
.348
5 72
24.30
.018
.067
1.00
12 70
010
.035
.0065
.0278
.0210
.0759
.0177
.0753
.0568
.2060
.0093
.0394
.0297
.1080
.0035
.OJ51
.01J4
.0411
*This is a floating point weighted total.
61
-------
TABLE 3 - CIIATTAHOOCHEE RIVER WATER QUALITY - DISSOLVED OXYGEN 1990
Conditions: (1) Guaranteed low flow 1250 cfs, (2) Background river BOD5 = 1.0 mg/1
& D.O. • 7.3 mg/1, (3) Storm Intensity .25 inches/hour - first 15 min
runoff effect only.
CASE 1 - Effect of Runoff of Each Area Individually on the River
Area CFS
Big Creek 2352
Foe Killer 824
Wlllco Creek 1195
Chatt. 1 343
Chatt. 2 654
Huntcllff 181
Roberts Dr. 105
Ball Mall 409
CASE 2 - Effect of
1. Ball Mill 409
2. Chatt. 2 454
3. Roberts Dr 105
4. Big Creek &
Foe Killer 3176
5. Huntcliff 181
6. Chatt. 1 &
Wllleo Cr. 1538
CASE 3 - Effect of
BOD5
6.15
6.89
2.24
13.10
7.99
13.10
10.20
6.66
Runoff by
6.66
7.99
10.20
6.34
13.10
4.66
Comb. BODs
4.4
3.3
1.6
3.6
2.9
2.5
1.7
2.4
Sequential
2.4
3.6
3.9
5.3
5.6
5.4
Net River D.O. * Comb
Final 2.9
Final 4.0
Final 5.7
Final 3.7 1.
Final 4.4
Final 4.8 1.
Final 5.6 1.
Final 4.9
Injection from Logically
4.9
3.7
3.4
2.0
1.7
Final 1.9
Runoff from Entire Area Injected at a Single
. BOD5
8
9
6
1
9
0
0
9
Grouped
9
9
9
7
8
7
Point
Net River D.O. *
Final 6.5
Final 6.4
Final 6.7
Final 6.2
Final 6.4
Final 6.3
Final 6.3
Final 6.4
Areas
6.4
6.4
6.4
6.6
6.5
Final 6.6
Final 6.6
^Hypothetical, based on assumptions stated in text.
62
-------
TABLE 4 - CHATTAHOOCHEE RIVER CONCENTRATIONS 1990
CONTAMINANTS OTHER THAN DISSOLVED OXYGEN - NO TREATMENT
Conditions; Guaranteed low flow 1250 cfs and zero river concentrations.
Total Runoff » 5863 cfs Flow = 7113 cfs
Contaminant Aat. RO Concentration River Concentration
COD. Ibs 15300 41.80 mg/1 34.50 mg/1
Total Solids, Ibs 498000 1360 mg/1 ' 1120 mg/1
Volatile Solids, Ibs. 20800 57 mg/1 47 mg/1
Total Collforms-cnt. 3710x1010 22324/lOOml 18400/lOOml
Fecal Collforms-cnt. 336xl010 2023/lOOml 1670/lOOml
Phosphates, Ibs ' 301 .82 mg/1 .67 mg/1
KJeldahl Nitrogen, Ibs 579 1.58 mg/1 1.30 mg/1
Nitrates, Ibs. 27.8 .076 mg/1 .063 mg/1
Copper, Ibs 76.4 .21 mg/1 .17 mg/1
Lead, Ibs. 89.2 .24 mg/1 .20 mg/1
Mercury, Iba. 26.6 .073 mg/1 .060 mg/1
Cadmium, Ibs. 3.6 .010 mg/1 .008 mg/1
Zinc, Ibs 127 .348 rng/1 .287 mg/1
Nickel, Ibs. 24.3 .067 mg/1 .055 mg/1
Chromium, Ibs. 12.7 .035 mg/1 .029 mg/1
Dleldrln, Ibs. .0278 .0759 ug/1 .0626 ug/1
PCB, Ibs .0753 .2060 ug/1 .1700 ug/1
DDD, Ibs .0394 .1080 ug/1 .0890 ug/1
P.P-DDT, Iba .0151 .0411 ug/1 .0339 ug/1
63
-------
NORTH FULTON COUNTY (ATLANTA) DRAINAGE AREAS WITH POTENTIAL IMPOUNDMENTS
Chattahoochee River
Mi.325.2
Dekalb Intake
49.5 MGD 1971
Mi.301.3
^Atlanta Intake
90.1 MGD 1971
NAME
Big Creek
Foe Killer
Willeo Creek
Chatt. 1
Chatt. 2
Huntcliff
Roberts Drive
Ball Mill
Totals
POP. 1970 POP. 1990
49500
20000
7800
31300
13400
16750
4500
9500
152750
Potential Impoundments
64
-------
D. Buffer Zones
The proposed alignment of the interceptors in the corridor
run between Riverside Drive and the Chattahoochee River from
approximately one (1) mile upstream of the Ball Mill Creek
force main river crossing to the pumping station for the Big
Creek Treatment Plant. The sewers involved are (1) Chattahoochee
II, (2) Ball Mill - north of the river, and (3) Big Creek Relief
Interceptors. A buffer zone along the river is required to
protect and enhance the recreational and environmental values
in this section of the corridor. The following conditions
apply for this interceptor alignment:
1. As recommended by ARC and BOR, the alignment should
provide an undisturbed buffer of 150 feet - measured from
the edge of the river to the nearest construction right-of-
way.
2. Where sections along the river cannot accommodate
the 150-foot buffer, representatives from applicable
Federal and State agencies will be consulted for advice to
insure design and construction techniques employed are
compatible with the preservation of the natural environment
immediately adjacent to construction rights-of-way.
65
-------
II. BENEFICIAL EFFECTS
A. Water Quality
The Chattahoochee River above Peachtree Creek in Atlanta
is classified under the approved Georgia "Water Use Classifica-
tion and Water Quality Standards" as "Drinking Water Supply."
It is also designated by the State Game and Fish Commission
as a trout stream. The treated sewage effluent will not
violate this standard. Criteria for the three pertinent
water quality parameters as set forth in the standards are:
a. Bacteria: fecal coliform not to exceed a geometric
mean of 1000 per 100 ml based on at least four samples
taken over a 30-day period and not to exceed a maximum
of 4,000 per 100 ml.
b. Dissolved Oxygen: A daily average of 6.0 mg/1 and
no less than 5.0 mg/1 at all times for waters
designated as trout streams by the State Game and
Fish Commission.
c. Temperature: Not to exceed 90° F In streams
designated as trout or small mouth bass waters by the
66
-------
State Game and Fish Commission, there shall be no
elevation or depression of natural stream temperatures.
Bacteria; Background data for the Chattahoochee River
over the past several years shows a marked reduction of fecal
coliform numbers in the river. For example, in 1965 measure-
ments at U. S. 19 and at Morgan Falls reveal a mean monthly
E. Coli of 5713 and 2093 respectively. (STORE!) Grab-samples
taken by the Atlanta Water Works from January through May of
1972 show that fecal coliform counts rarely exceed 1000/100
ml. Of 39 samples taken at the DeKalb County Raw Water
Intake, HY 19, Morgan Falls, and the Cobb County Intake over
the five-month period, no sample exceeded 4000 per 100 ml
established by the standard for the "fresh water supply" use
classification (the highest count was 3900 per 100 ml at
Morgan Falls).
It is noted that the Chattahoochee River receives
recreational use by people of all ages in the form of tubing,
rafting, and canoeing. These usages, which often result in
water contact, command a higher bacterial standard than "fresh
water supply" where treatment and disinfection preceded ingestion.
Bacteria kill can be achieved so that the quality of the sewage
effluent itself meets the "fresh water supply" classification.
67
-------
Dissolved Oxygen; A dissolved oxygen sag analysis was
conducted to determine the effects of the 6 mgd and proposed
ultimate 18 mgd sewage effluent on the Chattahoochee River.
In summary, the discharge of 6 mgd of sewage effluent will have
a nominal effect on the receiving stream. Certain basic
assumptions had to be made to determine the effect of 6 mgd
of sewage effluent on the Chattahoochee River. These are the
low flow conditions in the river; the river temperature; the
reaeration capacity of the river; the background
water quality of the Chattahoochee River.
The most conservative values for low temperature and
reaeration capacity were selected. It was assumed that there
is no significant tributary flow into the Chattahoochee River
between Willeo Creek and the Atlanta Raw Water Intake. Also,
it was assumed that there are no point sources of pollution
between the two points. Although existing water quality data
of the area indicate heavy pollution from Sope and Rottenwood
Creeks, and the Marsh Creek Sewage Treatment Plant is discharging
into the river, these conditions will soon be alleviated on
completion of the Cobb County Interceptor and sewage treatment
plant construction.
68
-------
Computations clearly show that D.O. levels in the
Chattahoochee River after mix will not fall below 6 rag/1
below the discharge of 6 mgd. Similarly, the discharge of 18
mgd of treated sewage effluent will cause D.O. levels to
depress only as low as 5.5 mg/1. A very localized depression
of oxygen concentrations is anticipated at the point of dis-
charge due to the low oxygen concentration in the sewage
effluent (2 mg/1 D.O.). This concentration, on which the
analysis was based, can be achieved on a continuous basis by
mechanical inducement of oxygen into the effluent or by adequate
and reliable operation and maintenance of the system as designed.
The zone of mix may be minimized by proper location of the point
of discharge in the river and by engineering to enhance dispersion
of the effluent.
Temperature; A mass balance analysis was conducted to
determine the effect of the 6 mgd and proposed utlimate 18 mgd
sewage effluent on ambient temperatures in the Chattahoochee
River.
Flow from Plant Temperature Rise in Water
6 mgd 0.5°F
18 mgd 1.25°F
The above data was generated by the analysis using low flow
-------
conditions in the river (500 cfs) and an estimated sewage
effluent temperature range of 72°F to 79°F.
B. Summary
The construction of sewerage facilities will be a
measure to preclude a decrease in water quality due to the
continuing increase in population. The facilities will
eliminate the need for septic tanks and package plants.
Physical and chemical water quality of the affected sections
of the Chattahoochee River and other streams can be preserved.
Public health as affected by sewage treatment can be protected.
Sewers in combination with other public facilities and an
operating land use plan, with responsible zoning and permits,
will provide for orderly growth and protection of aesthetic
areas, open spaces, ecological communities, and social well
being of the area.
70
-------
CHAPTER V
RELATIONSHIPS BETWEEN LOCAL SHORT-TERM
USE OF THE ENVIRONMENT AND LONG-TERM
MAINTENANCE OR ENHANCEMENT OF THE
ENVIRONMENT
The participation by EPA in funding of the proposed projects
is based on the objectives of long-term maintenance and enhance-
ment of the water quality of the affected streams and protection
of the public health, which is affected by sewerage facilities.
Short-term solutions for transport and treatment of sewage is
unacceptable if the eventual costs of sewerage works are higher
in terms of capital costs, damage to the environment, water
quality, and public health; and inflexibility in sewerage systems.
While the sewer lines may seem, by some people, to be over
designed, the overall projected rapid growth of the area requires
sewer sizes greater than necessary for the next 10 to 15 years,
as pointed out in Alternative No. 4. The rapid growth will occur
with or without the project or small sewer lines, this being so
because of the desire by many people to live in the Atlanta area
and specifically in the North Fulton County area. As mentioned
in the section, Population Projections, the projections for
River Ridge by EPA and the consultants for Fulton County must be
reconciled. Population projections for projects proposed for
71
-------
future funding will be checked at the appropriate time for
populations based on the latest land use plans and trends.
72
-------
CHAPTER VI
COMMENTS
A public hearing was held in the Fulton County Commission
Chambers on December 9, 1971, to offer the public an opportunity
to express opinions concerning plans for sewerage facilities in
the north Fulton County area. The major issues were (1) strong
objections from environmental groups regarding the original
location of the Ball Mill Creek interceptor sewer along the
river and the River Ridge interceptor sewer below Morgan Falls
Dam, (2) the population projections made by the consultants for
Fulton County and used to size the sewers, and (3) the seemingly
lack of consideration of any relationship between sewers, develop-
ment, land use plans, and urban runoff and water quality. The
first major issue noted above has been resolved by major realign-
ment of the proposed sewers. This was a direct result of the
public hearing on the Environmental Assessment Statement and
comments on the Assessment Statement by the Atlanta Regional
Commission.
EPA cannot dictate, approve, or disapprove land use plans
or development. These matters are functions of the State of
Georgia, Fulton, DeKalb, and Cobb Counties, and the cities of
Roswell and Alpharetta. The discussion by EPA on urban runoff
73
-------
and water quality is presented so that the general consequence
of the runoff on water quality in the north Fulton area can be
known. The areas covered by the proposed projects will develop
with or without a regional system, and the consequences of
development will occur according to State and local governments
land use controls and constraints. The projects proposed are
offered as a method to transport and treat sewage with the
funded projects meeting immediate needs. The alternative is
the use of lagoons, package plants, and septic tanks.
Subject to the restrictions and requirements noted in this
Impact Statement, the proposed facilities are recommended as
proposed.
73a
-------
APPENDIX A
URBAN RUNOFF COMPUTATIONS
A SIMPLIFIED FORTRAN IV PROGRAM AND PROCEDURE
FOR DEVELOPING CONTAMINANT CONCENTRATIONS AND
FLOOD WATER QUANTITIES FOR SPECIFIC RAINFALL EVENTS
By
Howard A. True
David W. Hill
74
-------
(S\ -
•i
UJ
C3
URBAN RiDiOFF CQf^lJTATIQf'IS
A Sir-FLIFIED FORTRAN IV PROGRAM A^JD PR3CEDURE
FOR DEVELOPING OWTAraN/WT COHCENTRI\Tia« AND
FLOOD WATER QUALITIES FOR SPECIFIC RAINFALL EVENTS
By
Howard A. True
David W. Hill
June 1973
Environmental Protection Agency
Surveillance and Analysis Division
Athens, Georgia
-------
A RUDIMENTARY METHOD FOR CALCULATING URBAN AREA RUNOFF
QUANTITIES AND CONTAMINANT CONCENTRATIONS
by
Howard A. True and David W. Hill
Environmental Protection Agency
Region IV
Surveillance and Analysis Division
Athens, Georgia
Urban storm water runoff is becoming of increasing concern because
of both pollutional aspects of small, frequent storms and flooding from
large, infrequent storms. This paper presents a simple method and a
short computer program to approximate both water quality and quantity
resulting from a given rainfall event on an urban area.
This work combines the research efforts by many people in a single
approach to an elusive problem. The procedure, although very useful,
is not "the last word" in urban runoff projections. It is presented in
considerable detail so that others may use it as is or make modifications
to fit particular circumstances. »
The process calculates population per acre from input data and this
key value is used to calculate curb miles and impervious acres through
use of the following regression equations:
C = 423.7 - 420.8 (0.8797)P &
C = specific curb length in ft/acre
P = population/acre
* Range of data 44 _< C _< 715 0.55 <_ P <_ 83.8
I = 91.32 - 69.34 (0.9309)p &
I = imperviousness in percent
P = population/acre
* Range of data 13 <_ I <_ 98 0.55 <_ P <_ 83.8
-------
* From thirty-two census tracts within the metro-
politan Washington, D. C. area. Imagery was
flown in June 1970 by NASA for the U. S. Geologi-
cal Survey as part of the census cities program.
Total area was 30,000 acres (12,150 ha).
The rational method7 was used for runoff rate and quantity calculations
for each sub-division of the total area. This method determines the runoff
in cubic feet per second at the point of concentration as follows:
Q = C I A
Q = runoff in cubic feet per second from a given area.
I = intensity of rainfall in inches per hour for a
duration equal to the time of concentration.
C = a coefficient representing the ratio of runoff
to rainfall.
A = the drainage area in acres.
NOTE: Exhibits 5 and 6 provide information for this
calculation.
Contaminant quantities and concentrations are now calculated for re-
port purposes. These reports display the required numbers for analysis
of flooding effects, input to a stream quality model or for simple cal-
culations of slug effects on stream quality. Exhibits 1, 2 and 3 cover
a hypothetical area for use in understanding the process and Exhibit 4
supplies the contaminant factors available at this time.
The user is referred to the section entitled "The Effects of Urban
Runoff in North Fulton County" for a full fledged analysis based on com-
putations from use of this process.
-------
PROCEDURE FOR CALCULATING URBAN RUNOFF QUANTITIES AND QUALITY
1. Obtain a map of the area in question.
2. Sub-divide the area for calculations and locate the receiving body of water.
3. Determine the acreage of each sub-area.
4. Obtain population of each sub-area for a reference year (e.g. 1970).
5. Project population for each sub-area (e.g. 1990).
6. Carefully review EPA-R2-72-081 "Water Pollution Aspects of Street Surface
Contaminants", Sartor & Boyd, URS Research Co., San Mato, Calif., 11/72.
7. Select contaminant factors from Table C-2 pp. 189-190 of the publication
stated in 6. Selected values should be from nearest city or the weighted
average can be used if desired.
8. Review write-up "Estimation of Imperviousness and Specific Curb Length
for Forecasting Stonnwater Quality and Quantity", Graham, Costello &
Mallon, Metro Wash., D.C. Council of Governments, 3/20/73 or use popu-
lation oriented regression equations included in the FORTRAN program
attached.
9. Punch a set of 40 factor cards as illustrated later in this writeup.
10. Punch a set of area features cards and a total area card for the reference
year and projection year. See text for instructions.
11. Punch a storm event card for each storm size desired. See text for
instructions. See text for possible sources of storm information.
12. The factor cards are used for all runs; however, two runs are made
independently with area feature decks to allow a weighted total
report to be produced by the computer. For water quality reports a
single normal storm event card will be used in both runs (e.g. 1970
and 1990); however, additional storm event cards for return years of
2, 5, 10, 25, 50 and 100 (from rainfall-intensity-duration-frequency
curves) can be added to get flood reports in the same runs.
13. Computing time requirement is approximately 0.2 second per report on
an IBM 370/155. Time in seconds = 3 + (no. of storm cds. x no. of
area cds. xO.2).
14. Factor cards 1 through 10 are reserved for common water quality para-
meters with cards 5 and 6 reserved exclusively for coliforms. Factor
cards 11 through 19 are for nutrients, cards 20-29 for metals and
cards 30-40 for pesticides. All 40 cards are required although as few
or as many as needed are punched with contaminant information.
-------
15. The E format is used principally in the area report because of wide
range of magnitudes to be encountered.
16. The present limit of 20 identifiable area cards and 1 total area card
can be expanded through minor program changes. These cards are held in
arrays for application of multiple storm events.
17. The final step is the manual extraction of calculated values to develop
tables and graphs to support a narrative statement concerning
water quality effects on a receiving water body and flooding effects
within an area or area group.
-------
DEMONSTRATION RUNOFF AREA
2000 acres
pop 1970 (2000)
pop 1990 (8000)
5000 acres
pop 1970 (2500)
pop 1990 (25,000)
1500 acres
pop 1970 (6000)
pop 1990 (30,000)
-------
INFORMATION COVERING DEMONSTRATION AREA «i
RETURN YEARS = 1) '
INFORMATION COVERING
RETURN YEARS = o
DEMONSTRATION AREA
POPULATION- 1970
_P13
FECAL COL1FORMS ____ 0.2>JOE»10 O.SbbE»12
34589.6
_._. 3134.7 ._
•NUTRIENTS».±_
PHOSPHATES 0.260E*00 0.71bE«01 0.247E«00
KJELOAHL.NITROGEN Ot500E»00. 0.137L»02 0.475L-00.
NITRATES 0.240E-01 0.660E»00 0.228E-01
PHOSPHATES
KJELOAHL NIJHOGEN_
NITRATES _. _"_
_ ••METALS'*
0.260E*00 0.497E»02 0.127E»01
. 0.bOOE«00 0.9S6E»02 0.2'»SE*01
0.2«»OE-01 0,«.54E*01 0.11bE*00~
ZINC
COPPER
LEAU
NICKEL
MFRCUPY
CHROMIUM
CADMIUM
0
0
._. 0
.... 0
0
0
0
.not»oo
.6MJE-01
.770E-01
.210E-01
.230E-01
.110t-01
.310E-02
0.
0,
0.
0.
0.
0,
0.
.302E*01
,181E*01
.212E*01
,577E»00
,h32L«00
,302E»00
.8S2E-01
0,
0,
0,
0,
0.
0,
0,
>104E»00
.627E-01
•731E-01 . . _
.199E-01
.2HE-01
.104E-01
••PESTICIDES** ,
D1ELOKIN_
PCB
b-'-ODT
_0.2*>OE-04 0.660E-03 0.228E-04
0.6bOE-04 0.179E-02 0.617E-04
0.3*OE-04 0.93^E-OJ O.J23E-04
_ 0.130E-04.0. J57E-03 0.12JE-0'«_.
ZINC
COPPER
LEAD
NICKEL
MERCURY
CHROMIUM
CADMIUM
••PESTICIDES"
DIELDRIN
PCH
BP-DDT
P.P-ODT
O.llOE'OO 0.210E*02 0.539£»00
0.600E-01 0.1?6E»02 0.324E»00
0.770E-01 0.147E*02 0.37HE*00
_, 0.210E-01 0.402L*01 0.103E*00
0.230E-01 0.'.'fOE*01 0.113E«00
0.110E-01 0.210E*01 O.bSflE-Ol
0.310E-02 0.593E*00 0.152E-01
0.240E-04 0.459E-02 0.118E-03
O.f»50t-04 0.12iiE-01 0.31"E-03
0.340E-04 0.6bOE-C2 0. 167E-03
0.130E-04 0,?'.yE-02 0-bT7F-n<.
EXHIBIT 2/i
•NOTE CONC. ASSUMED 90% WftSHOFF OF CONTAMINANTS IN 15 MIN, -NOTE CONC. ASSUMED 90% WASHOFF OF CONTAMINANTS IN 15 MIN.
-------
INFORMATION COVERING
NETUHN YEAH^ = o
DEMONSTRATION AREA »2
INFOWMATION COVERING
RETURN YEARS = 0
DEMONSTRATION AREA »2
POPULATION-1970 6000.0
.POP. DENSITY/ACRE 4.0
A*EA ACPES
MlLEb OF CU3rt
* I^PEKVIOUbNESS"
iMPtHVIOUS ACRES
WAIN INTENSITY
_OU?ATIO.N MJ.M.
ANN. HAINFALL IN.
• ANN. SNOWFALL IN.
_ PKECIP. (JAYbXYR.
FPZ. DAYS/YR.
RUNOFF CFS
HUNOFF ACHE-FT.
WUNOFF CU. FT.
H.O. C.F. 15 MIN.
_ PARAMETER
RODS
COU
TOTAL SOLIDS
VOLATILE SOLIOS
_ TOTAL COLIFORMS
FECAL COLIFOHMS
"NUTKIENTS"
PHOSPHATES
.KJELOAHL NITROGEN
NITRATES _.
_ "METALS"
ZINC
COPPER
LEAD
NICKtL
MEHCURY
CHROMIUM
CADMIUM
"PESTICIDES" . _
_ OIELORIN
PCB
HP-DOT
P.P-OOT
1500.0
48.8
39.2.
588.7
0.25
120.0
0.1
107.0
73.0
178.0
.29.4
1281H05.0
160225.6
COEFFICIENTS
CNT OH LHS/CM
0.200E*01
0.132E»02
0.430E»03
0.1dOL»02
0.320E»11
0.260E*00
0.500E>00
"0.240L-01
0.110E-00
0.660E-01
0.770E-01
0.210E-01
0.230E-01
O.L10E-01
0.310E-02
0.240E-04
0.6SOE-04
0.340E-04
0.130E-04
• — -
• --
—
— •
_. . . .
• ... _
- -
TOTAL LOAD «CONC.INIT. IS
CNT OR LBS . MG/L«_. CNT/100
0.97f>E«02 0.873E«01
0.644E»OJ 0.579E»02
0.210L*05 0.189E*04
0.378E»03 0.790E*02
0.156E»13 30958.
0.141E*12
0.127£»02
0.117E»Ol
0.537E.Q1
0.322t«0l
0.376E»01
0.102E*01
0.112E«01
0.5J7E»00
0.151E«00
0.117E-02
0.317E-02
0.166E-02
0.634E-03
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
. 2805.
114E*01
10bE«00
4fl3E*00
290E-00
338E*00
922E-01
101E*00
48JE-01
136E-01
105E-03
285E-03
149E-03
570E-04
PQPULATION-19QQ
. POP. DENSITY/ACR
AREA ACRES
MILES OF CUr»B
IMPtHVIOUS ACRES
PAIN INTENSITY
.. DURATION MIN.
ANN. RAINFALL IN
ANN. SNOWFALL IN
.PHECIP. UAYS/YR.
FSZ. OAYS/YR.
RUNOFF CFS
frUNCFF ACRE-FT.
RUNOFF CU. FT.
... . R.O. C.F. 15 MIN
MIN.»
ML PAPAMETFR
BODS
COO
TOTAL SOLIOS
VOLATILE SOLIDS
3 TOTAL COLIFOP1S
6 FECAL COLIFORMS .
"NUTRIENTS"
PHOSPHATES
KJELDAHL N1IROOEJ
NITRATES
••METALS'"
ZINC
COPPER
LEAD
NICKEL
MERCURY
CHROMIUM
CADMIUM
••PESTICIDES"
~ DIELOR1N
PCR
hP-ODT
P.P-OOT
30000.0
1500.0 _
. 111.2
74. H
1121.4
0.2S
1PO.O
. 0.1 _..
107.0
73.0
271.2
1952973.0
. 244121.6
COEFFICIENTS
CNT OR LBS/CM
.. .. ~0.200E»01
0.13^F»0?
0.430E«03
0.1dOE*02
0. 320E* 1 1
0.290E«10
' 0.260E*00
* 0.500E.QO
0.2^tOE-01
0. 1 IOE'00
0.660F-01
0.770E-01
0.6 WASHOFF OF CONTAMINANTS IN 15 MIN.
sa
a
H
ro
-------
INFORMATION COVEKING
RETURN YEARS = 0
DEMONSTRATION AREA 03
INFORMATION COVERING
RETURN YEARS = 0
DEMONSTRATION AREA
POPULATION- 1970
POP. DENSITY/ACRE.
A^EA ACRES
MILES OF CUKB
% I«PE»V!OUSNtSS
IMPERVIOUS ACPES
RAIN INTENSITY
DUHAT ION MIN.
ANN. RAINFALL IN.
ANN. SNOWFALL IN.
PHLCIP. DAYVYK.
FHZ. DAYS/YR.
RUNOFF CFS
HUNOFF ACPE-FJ.
RUNOFF CU. FT.
R.O. C.F..1S MIN.
PARAMETER
BODS
COD
TOTAL SOLIDS
VOLATILE SOLIDS
TOTAL COLIFOHMS
FECAL COLIFOHMS
• »NI.IT pifNTS00
PHOSPHATES
KJELUAHL NITROGEN
NITRATES
••MFTAl S*°
ZINC
COPPER
LEAD
NIC»\EL
MFPCURY
CHKOMIUM
CADMIUM
••PESTICIDES*'
DIFI (?RIN
PC4
nP-»DT
p.p-noT
3000.0
1.0
2000.0
_ 20.3
26.8
535. 4
0.25
120.0
48.5
0.1
107.0
73.0
193.7
32.0
1394637.0
174329.0 „
COEFFICIENTS
CNJ OR LBS/CM
0.200E»01
0.132E»02
0.430E*03
0.1BOE»02
0.320L»11
. 0.290E*10
0.260E«00
O.bOOE.OO
. . 0.240E-01
0.110E»00
0.660E-01
0.77QE-01
. 0.210E-01
0.230E-01
0.110E-01
0.310E-02
0.240E-0*
0.6bOfc>04
0.3-'»OE-C4
0.130L-04
--
—
TOTAL LOAD
CNT OR L6S
0.405£»02
0.26H£*03
0.87?E»04
0.36bE*03
0.6'»C'L«12
0.588E»11
0
0
0
0
0
0
0
0
0
0
0
0
0
0
.527E»01
.101L*02
,«»87E»00
.223E«01
.13<>E*01
.lbfat»01
.^26E»00
,46'>E»00
.223E»00
.b28E-01
.487E-03
.132E-02
.6813
.189E»12
.16<
-------
INFORMATION COVERING
RETURN YEARS = o
TOTAL AREA (1*2*3)- 1970 POP.
INFORMATION COVERING
RETURN YEARS = 0
TOTAL AREA « 1 • 2 » 3 > - 1990 POP.
POPULATIOM-1V7Q_
POP. DENSITY/ACRI
APEA ACPES
MILES OF CUr»fa
* IMJ'FUVIOUSNESS
IX"t"VIOUb AGUES
PAIN INTfNSITY
1>..M.UION MIN.
AMJ. RAINFALL IN
ANN. SNO«FALL IN
PHECIP. UAYS/YH.
FHl. OAYS/Yr».
RUNOFF CFS
PUNOFF ACPE-FT.
PUNGFF CU. FT.
K.O. C.F. 15 MIN
lObOO.O
E 1.2
85oo.o
96. S
27.6
23/.5.1
0.25
120.0
'•B. 5 .__.
0.1
107.0
73.0
835.4
138.1
6014B08.0
. 7518^0. 9
POPULAT I ON- 1090
POP. DENS1T1/ACRE_
AEL
MFftruPY
CHROMIUM
CADMIUM
«°P£STICIDE!>"
niFi URIN
PC«
BP-UUT
P.P-DDT
0
0
... 0
0
0
0
0
0
0
0
.IIOE'OO
.660E-01
.770E-01
.210E-01
.230E-01
.110E-01
.310E-02
.240E-04
.650E-04
.340E-04
0
0
0
0
0
0
0
0
0
0
,<.04E»02
.243E»02
.283E«02
.772E-01
.404E«01
,114£.01
•
•
•
a
eB2E-02
239E-01
125E-01
478E-02
0
0
0
0
0
0
0
0
0
0
0
•
•
•
•
•
•
•
•
•
•
•
571E«00
3'OE.»00
400E»00 _
109E»00
119F.OO
571E-01
161E-01
125E-03
33BE-03
177E-03
<>75E-04
a
(—1
03
•MOTE CONC. ASSUMED 90* WASH.OFF OF CONTAMINANTS IN 15 MIN. «NOT£ CONC. ASSUMED 90% WASHOFF OK CONTAMINANTS IN 15 MIN.
-------
EXHIKTT 3
INFORMATION COVERING
RETURN YEARS
DEMONSTRATION AREA
= 3=5
10
25
50
POPULATION-]97Q 2500.0
-£OP._DENSITY/_ACP_L 0,5. _
AREA ACrtES _ _5000.0
MILES OF CURB 27.5
2500.0
IMPERVIOUS ACRES
RAIN INTENSITY
.DURATION UIN.
1220
1
120
ANN. WAlf.FALL IN. 46
ANN. SNO»FALL IN. _ o
_PRECIP. tmS^YH, 107.
FR2. DAYS/KH. 73
RUNOFF CFS 1854
.RUNOFF. ACNE-FT. .. .306
RUNOFF CU. FT. 13353475
R.O. C.F. 15
.9
.00
.0._
.5.
.1 ..
•.0.
.0
.6
.6.-
.0
.0
.5000.0
27.5
24. 4_
1230.9
1.40
— 120.0_
_4b,5.
0.1
-107..Q.
73.0
3596.5
2bOO.O 2500.0
0..5 0..5.
.— 5000.0 5000.0
27.5 27.5
24. V
1220.9
= 100
2500.0
24.4._
1220.9
1.60
- 120.0
4^,5
_ . . 0.1..
107. 0_
73.0
2967.4
490. 5 _
1.80
1 ?n . o 1
i.« C
0.1..
107.0 i
73.0
333B.4 37,
— 551.8 6
21J65b!?2.0 2403&25G.O
D_ 33045J1..0,
26706944.0
3338363.0
POPULATlO
.POP. DENSITl/ACP
AREA ACRE'S
MILES OF CURB
% IMPEPVIOUSNESS
IMPERVIOUS ACHES
RAIN INTENSITY
.DURATION MJN,
ANN. RAINFALL IN
ANN. SNOWFALL IN
PRECIP. 0AYS/YR.
FR2. DAYS/YK».
RUNOFF CFS
.RUNOFF ACRE-FT.
RUNOFF CU. FT.
P.O. C.F. 15 MIN.
3499.5
57fa.<,
0 25196432.0
0 314Y5S3.0
48.5
0.1
07.0
73.0
4499.4
1 7-O.7
0 3239540SJ.O 35994~&96."o
-4499360.0
0.7.0_
73.0
4080.2
674.4_
29377632.3
.3672202.0
25000.0
5.0
5000.0
191.3
42.H
2142.4
2.20
120.0
_46.5
0.1 _
5499.2
909.0_.
39594368.0 _
..4949294.0
INFORMATION COVERING DEMONSTRATION AREA «2
POPULAT ION- 1970
POP. DENS1 fY/AC»E_
AREA ACRES
MILES OF CURB
% IMPERVIOUSNESS
IMPERVIOUS ACRES
RAIN INTENSITY
DURATION MIN.
ANN. RAINFALL IN.
ANN. SNOWFALL IN.
_PRECIP._OAYS/_YiN[.__
FR2. DAYS/YS.
RUNOFF CFS
RUNOFF ACrtE-FT.
RUNOFF CU. FT. . .
R.O. C.F. 15 MIN.
POPULATION-1990
.POP. OENSITY/^CRJL.
AREA ACHES
MILES OF CURB
.% IHPERV10USNESS
IMPERVIOUS ACRES
RAIN INTENSITY
DURATION MIN.
ANN. RAINFALL IN..
ANN. SNOWFALL IN.
.PRECIP.. UAYS/jrjL,
FP2. DAYS/YR.
RUNOFF CFS
.RUNOFF ACHE-Jit.
RUNOFF CU. FT.
P.O. C.F. 15 MIN.
6000.0
1500.0
46.8
39.3
586.7
1.00
120.0
48.5
0.1
107.0
73.0
712.1
117.7
6000.0
4.0
1500.0
48.8
39.2
588.7
1.40
J2Q...O_
48.5
0.1
107.0
73.0
997.0
164.8
6000.0
4.0
. -. 1500.0
48.8
39.2
588.7
1.60
i?o...p_
48.5
0.1
107.0
73.0
1139.4
188.3
6000
4.
1500.
_ 46.
39.
.0
0
0
8
2
588.7
1.60
120.0
48.
0.
107.
73.
1281.
211.
5
1
0
0
8
9
5127219.0 7178104.0 8203554.0 9223997.0
64.0902.2 ,897262»a_1025'.44.1 _ULS3«)-4.0
30000. ( 30000.0 30000.0 30000.0
20.0 20.0 20.0 20.0
1500.0
. . .111.2
74.8
1121.4
l.OC
120.0
4d.5
. . ..0.1
107.0
73.0
1085.0
179.3
7d 11 694.0 1
1500.0
111.2
74.8
1121.4
1.40
120.0
1500. 0_
111.2.
74. S
1121.4
1.60
120.0
1500.
.111.
74.
1121.
1.
120.
fcfl.S 4S.5 4B-
0.1.
107.0
73.0
1519.0
251..JL.
09j«>64c3.U
13670?0.0
0.1
107,0
0.
107-
73.0 73.
1736.0 1953.
286.9 322.
1249903-.0 14061403.
0 .
2
fl
4
80
0
S
1
0
6000.0
4.0
-.. .1500.0
46.8
39.2
568.7
2.00
120.0
48.5
0.1
107.0
73.0
1424.2
235.4
10254«<.0.0
30000.0
20.0
1500.0__
.111.2
74. H
1121.4
2.00
120.0
0.1
107-0
0 73.0
0 2170.0
o"l?62~3783!"o"i
0 1952972.0
6000.0
4.0
1500.0
4B.H
588.7
2.20
120.0
48.5
0.1
107.0
73.0
1566.7
25-J.O
30000.0
20.0
1500.0
111.2
74. fl
1121.4
2.20
120.0
0.1
107.0
73.0
2387.0
394.5
.718M60.0 ._
2148270.0
-------
EXHIBIT 3 (cont)
INFORMATION COVERING
RETURN YEARS
DEMONSTRATION AREA «3
2 =5
POPULATION-197Q
.POP. DLN'JIT VACPL.
AREA AC^ES
MILES OF CURB
.% IIPEP-VIO'JS'.'LSS.-.
IMPERVIOUS ACPES
RAIN INTENSITY
DURATION f'IN.
ANN. RAINFALL 1M.
ANN. SNOWFALL IN.
PREC1P. 1>AYS/YK._
"FRZ. OAYS/YH.
RUflOFF CFS
. RUNOI F ACr^C-T T .
RUNOFF cu. FT.
_R.O. C.F. 15 KIN.
2000.0
1.0
2000.0 .
20.3 _
26. B__
535.4
1.00
120.0
t<3.5_
0.1 .
73.0
774.8
~5l37-jb'->l".0 ~7
2000.0 20
1.0
.2000.0 200
20.3 2
2S.fi 2
535.4 53
1.40
120.0 12
<.d.S 4
0.1
107.0 10
73.0 7
1084.7 123
_.. H9.3 20
HOSS'j^.O »^2568
07624b.O 1111-71
1.0
2000.0
-l.D
.2000.0 2000.0
._. 20.3
26.8
b.4 535.4
1.60 1.80
JL20.0.
= SO
2000.0
I ..0__
100
2000.0
2000.0. 2000.0_
20.3 20.3 .
48.
48.5...
0.1 0.1.
7..0 102..0
73.0 73.0
139-..6
230J5_
0,
1QJ.O.
73.0
1704.6
.1 281.
.0 12272813.0
Ii!bbl74.n 1 114MB.0 _15341U1.0_
POP. DENSITY/ACRE
AREA ACPLb
MILES OF CURB
% IMPERVIOIIV.'ESS.
" IMPERVIOUS ACRES
RAIN INTENSITY
..DURATION M1N,
ANN. RAINFALL IN.
ANN. SNO»FALL
.PWECIP. DAYS/YH.
FRZ. DAYS/YP.
RUNOFF CFS
. RUNOFF AC^E-FT
PUNOFF C'J. FT.
K.O. C.F. 15 MIN.
'E
J.
J.
*j.
8000
4,
2000.
65.
39.
7B5.
1.
1?0.
48.
0.
107.
.0
0.
0
0
2
0
OC
0
5
1
0
73.0
949.5
156.9
6436291.0
854536.2
8000
4.
_2000.
65.
39.
705.
1.
120...
4d.
0.
107.
73.
1329.
_ ...219.
9570805.
11963SO.
.0
0.
0
0
?
0
40
0
5
1
0
0
3
7
0
0
flOOO.O
4AQ_
2000.0
65.0
19.2
785.0
1.60
120.0
48.5
0.1
107.0.
8000
4.
2000.
65.
39.
785.
1.
J20,
_ 0.
107.
73.0 73.
1519.2 1709.
. 2bl,l. ... 282.
10<*3H069. 012305325.
.0
0
0
0
2
0
80
0
1 .
0
0
1
5.
0
8000
4.
2000.
. . . 65.
39.
.0
0
0
0
?
785.0
2.00
120.0
48.
.0.
107.
73.
1899.
313.
13'j72563.
170V072.
5
8000.0
4.0
. .. 2000
65
785
2
120
48
>._ 0
0 107
0 73
0 2088
9 345
0 15039829
0__1879V70
.0
.0
.0
.20
,0
.5..
.1 . .
.0
.0
.9
.3
.0
.0
INFORMATION COVERING TOTAL AREA ( i » 2 • 3 )
POPULATION-1V70
POP. DENSITY/ACRE.
AREA ACRES
MILES OF CUi'ri
IMPERVIOUS AWES
RAIN INTENSITY
DURATION MJN,
ANN. RAINFALL IN.
ANN. SNOnFALL IN.
PRECIP-. DAYS/YR,
"FRZ. DAYS/YR.
RUNOFF CFS
RUNOFF ACRK-FT.
10500.0
1.2
8500.0
96.5
27.6
2345.1
1.00
120.0
48.5
0.1
107.0
7J.O
3341.6
552.3
RUNOFF CU. FT. 24059248.0 :
_R.Q._C.F.._JLf>-t!lN.. 3007404.0
10500.0
1.2
8500.0
96.5
27.6
2345. 1
1.40
120.0
48.5
0.1
107.0
73.0
4678.2
773.3
<«2103&3!o
10500.0
1.2
8500.0
96.5
27.6
2345.1
1.60
120.0
48. b
0.1
107.0
73.0
5346.5
883.7
10500.0
1.2
, 8500.0
96.5
27.6
234S.1
1.80
120.0
48.5
0.1 _
107.0
73.0
6014.8
99_4._2
10500.0
1.2
8500.0
96.5
27.6
2345.1
2.00
120.0
48.5
0.1
107.0
73.0
6663.1
_ 1104.6
10500.0
1.2
8500.0
_ 96.5
27.6
2345.1
2.20
120.0
'•a.. s.
0.1
107.0
73.0
7351.4
1215.1
3d-94BOO.O 43306t>'«0.0 48113464.0 52930320.0 .
4ol 1B-.C.O .5jtl312S..O_ 6014807.0 fe61fi2
-------
Table C-2
QUANTITIES OF POLLUTANTS POUND OS STREETS (Ib/eurb mi)
EXHIBIT 4
SAD
PmlllANT JOSF'I
II'HJ. 16
1 IXI 310
Ihjcurb ml
Mi' 0 1O
Ib/iurb •!
Ml, ]]
tti i urb • !
• 11
Ih/iurb •!
Ib/rurb •!
Id 0 0030
Ibjcurb •!
• i 0 If
Ib/iurb • !
*. 1 9
Ib/mrb •!
/• 1 4
Ib'rurb •!
fu 0 4ft
Ib/rurb ml
t, o to
Ib/rurb bl
H| 0 30
Ib/rurb •!
lolil hrivy B«l»lff 4 4
Ib, curb •!
Tolil Collforb*
•illloa/rurb bl
frcil CollfArwr.
• i II Ion/curb •!
tixlrln 1.0
lo~* Ib/curb •!
Ol«larm II
Hi'8 Ib/curb ul
KU lira
Ifl"' Ib.curb ml
in"6 Ib/cuiH • !
» p-DOT no
!"-• Ib.rurh •!
LliuliM IT
|n~s Ib/rurh »l
Mrlltyl Pxrilhlnn 1O
In'6 lbi
Ul.,) 6T
1""* Ib/curb ml
i •Ht.rt
• 9 11
30 41
0 M 0 IT
0 19 0 091
1 9 1.4
•90 1700
0 0031
0 Oil
1 >
1 1
0 M
0.041
•
4 1
49
1 0
0
10
1440
•900
1 0
9 1
0
0 9
Mill- SAI
DILI'S H*r JHbF-ll
1 9 61 93
1» 10 400
019 10 49
0 11 0 Oil 0 IT
1.1 1.9 II
1400 1000 *HUO
0.0036
0 Oil 0 Oil
0.4T 0.90
11 0 II
0.13 0 010
0 49 0 14
0 Oil
14 19
41 Tl
11000 5*0
00 0
IT 1.0 IT
•9O IOOO IOOO
1400 ITO 0
M X ITO
00 0
00 0
U 100 110
AlrNAIr •Miinni
rWJ»l> mVIHIfAl I'HI- All/ A. Ill
ATLATM TtLM II SMTTLC HI.VI HTIm All
19 14 10 41 II li. 0 mm 14
19 M 94 IT n ll» 1 1 -1
0 26 0 94 11 41 II in o » II
0 014 0 Oil Oil 0 Oil 0 043 II o«n n »3 ,i i.O!
041 0 40 1.9 O M 14 II OT4 11
410 110 110 4<0 1900 HIM o Tl I4im
o mill o ami o OM
0011 0.011 O 031 0011 0060 0041 O.T1 II IU
0 077 0 OJO 0.11 0 90 0 61 0 60 0 II II 91
0 II 0 Oil 0.34 0 3T 0 T» 0 13 0 19 n IS
o oca o on o 09i o OTS on o 10 o 19 « m
0 (III 0 Mil 0 OI» 0.011 0.11 Oil 091 U II
0 0» 0 010 0 Oil 0 014 0 Oil 0 OT9 O 91 O ii7J
0 11 0.11 .11 II 19 . . |i
11 ITO
-------
N IN iscms
ATLANTA AIlt.\<:>
KX!!IBIT 5
• -
—
—
—
\
\
\
\
V
s
-^
•—
I
\\
\\
\
v\
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r^>
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^
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-~.
1 •
~~
1
ft
__
^— _
1 —
H
E Til 111 1
|
. »'
I
* ,
1 — . .
KTtM»l
tntr~Vttt
su K:«T
0ȣ HGKI
110 m«
tssi.stit
,
~
=
i
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i
;». i
=" L-l
ILAI
*-' -
i iiirci:
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—
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— • —
i
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!
19U !"(,') IViMul cnrd C.ilf nrt.ir Yrv 1 •»(!«
Norni.il M.i\iitr,uu .Viininr.im M.minum Monlli CriMti-vtin
Konlli Total'-1 MoulM) Muiitlily M llutin^' Total l-tllnuis
Januii) 4A4 10.82 1.-J2 3.27 285 1.65
February 4-5l 1^7 0.99 567 3.20 0.71
Much 5.37 11.51 2.73 4.S2 400 153
April 4.47 986 1.45 4.26 570 2.69
May 3.16 7.83 0.32 5.13 763 4.34
June 3. S3 7.52 0.74 3.14 1.00 0.43
July 4.72 11.26 1-20 5.44 2.6-4 1.51
August 3.60 869 0 8S 5.05 612 1.79
Stplcmfccr 3.26 7.32 0.26 5.46 3.74 1.89
October 244 7.53 T 3.27 1.53 069
November 2.96 15.72 0.41 4.11 2.67 1.44
Drcrmber 4.3S 9.92 1.08 3.S5 3.27 1.11
I I is il 14 ig
OURITIOII Pours)
RAINFALL INTENSITY-[JURATI ON-FREQUENCY CURVES, ATLANTA. GEORGIA
-------
EXHIBIT 6
0.
10
15 ZO 30 40 50 60
MINUTES
DURATION
4 5 6 8
HOURS
20 Z4
SOURCE: U.S. WEATHER BUREAU
TECHNICAL PAPER NO.25
PERI CO OF RECORD: 1903 - 1951
FREQUENCY ANALYSIS BY METHOD OF
EXTREME VALUES, AFTER CUH6EL.
CITY OF ATLANTA, GEORGIA
RAINFALL INTENSITY-
DURATION -FREQUEHCY CUF..ES
-------
EXHIBIT 7
D/STA CftRT>5
5*H-
Ct H-Z3
M21
I01BOD5
i02COO
'03TOTAL SOLIDS
,0'-.VOLATILE SOLIDS
05TOTAL COL IFOR'S
2.0i
13.2
*30.0
18.0.
'32GOC.OE-"3
06FECAL. COLlFOr^b
07
OH
2SOO.OE»6i
-C.urtR.twT
10
.HPriC'SPH/JF.5_
*12KJELOfl"iL N!
13NJTWATLS
....4--
i
_.j?»» 3_:_J_6y?*rs_£'»"• 9.
s /#• ~~
f«
-TtTflt:- /WP H^T HM£ ft t <* >c*. XC
*W» fl"WS_/efl /'tf'i.MTliM.^Afn.
1
K~
m
or—
«
--
i
ff
Sc-
|ss
207 14C ' .11-
21COPPER .Oftb
22LEAD ' .077
23NICKEL .021
2fc«.E-'CUPr .023
?5Cnf>OMlij" ' .011
26CAOM1IJV ! .0031
?7 : |
?3
?Q
300IELOWIN : 2<..OE-b
310CJ i 6S.OE-6,
33MFTM-OXYCHLOD ' .0
3<.P,P-OOT 1 13.0E-6
3bENO"»IN .0
37L1NOANE j .0
30 1
39
40
OEMONSTSflTIOr, ArEA 3?
DEMONSTDATION AStA «3
f^A t ft* 1 flV »"
* rv( ff ff^m • ltf&
250'J.O 5000.0 19?'o
6COC.O IbOO.O '1^70
2000.0 2000.0 1970
TOTAL APEA ( 1 * 2 • 3 ) - 1970 POP. &SV*. AtJMH 1970 1
Rt-t\M^ CRGH H4R£
SlfOEMONSTPATION APE* -1
Srt DEMONSTRATION A-EA ->2
"••v
DEMONSTOAT lOfJ AK£A »ji
i '
25000.0 5000.0 1990
30000.0 1500.0 1990
bObO.O 2000.0 ly»0
| y (TOTAL AREA < 1 « 2 • J ) - 1990 POP. . Si/bUt JUflA
-------
EXHIBIT 8
TABLE ll-l. Surface V/alcr Criteria for Public Water Supplies
Permissible Desirable
Constituent or characteristic criteria criteria Pardfrdph
Physical:
Color (color units) 75 <10 ]
Odor Narrative Virtually absent 2
Temperature J -. do Narrative 3
Turbidity do Virtually absent 4
Microbiological:
Cohfoim crpamsms 10.000/100 ml' <100/100ml1 5
Fecal coliforms - 2.000/100 ml1 <20/100 ml ' 5
Inorganic chemicals: (mg/l) (mc/l)
Alkalinity Narrative Narrative 6
Ammonia 05 (as N) <0 01 7
Arsenic * 005 Absent . 8
Dariuin • 1 0 do 8
Boion * 1 0 do 9
Cadmium* . 001 .' do 8
Chloride • 250 <25 8
Chromium.' hoxavalent 005 ...Absent 8
Copper • 1 0 Virtually absent 8
Dissolved oxygen >4 (monthly mean) Near saturation 10
>3 (individual sample)
Fluoride • Narrative Narrative 11
Hardness • do do .. 12
Iron (filterable) 03 ...Virtually absent 8
Lead » 005 Absent ._ 8
Mancancse0 (fil'eiable) 005 do 8
Nitrates plus nitrites • 10 (as N)._ Virtually absent 13
pH (range) 60-85 Narrative 14
Phosphorus • Narrative do ID
Selenium e 001 ...Absent 8
Silver • 0*05 do 8
Sulfatc • 250 <50 8
Tolal dissolved solids • 500 <200 16
(filterable residue).
Uranyl ion • 5 Absent 17
7mc • 5 Virtually absent 8
Organic chemicals:
Catbon cliloroform extract" (CCE) 015 _ <0 04 18
Cyanide • 020 Absent 8
Mcthylene blue active substances* 05 ...Virtually absent 10
Oil and crease c Virtually absent ...Absent 20
Pesticides:
Aldrin • 0017 do 21
Chlordane • 0003 do 21
DOT' 0042 do ?1
Dicldrm « 0017 do 21
Endnn • 0 C01 do 21
Heptachlor ' 0018 do 21
Hcptachlor epoxide • 0018 do 21
Lmdane * 0056 do 21
Mcthcxychlor • 0035 do 21
Orcanic phosphates p'us Ol3 do 21
carbamates.0
Toxapl.cne • 0 005 do 8
Herbicides
2,4-D plus 2.4.5-T. plus 2.4.5 TP • 0 1 do 21
Phenols * 0 C01 _ do 8
Radioactivity: (PC/I) (pc/l)
Gross beta e 1.000 <100 8
Radium 225 e 3 <1 8
Strontium SO • .10 <2 8
• Thp defined treatment process has littte effect on this limit may be relaxed it fecal coliform concentrj*t en dies net
constituent e«ccccl n-c scrcilnd limit
1 Microbiolrqical linn's are ironthl/ ^nfi—etc a.er*cps -As r.T ith en in choiines'rrase inhibition It m--/ i: incc*
based upon an adequate number of sjtiple* lotal con'orrn sary to resent to f en lo.vcr concentrations for bj c csm
pounds 01 miAlurcs Sec par 21
-------
— C
TOUF - EPA 5/25/73.
00 « I=l.*0
wFSUO.h) |N| (I). (1NV(I.J»«J=I«5,.PCMIM»
8 Fpm'ftl ( |Z.b&<*.F 10.1) . ..... - .
<* CO'iIIUU'E
»W1 =0.0
AC"£T =0.0 . - --. ---- ----------- -
10 2EftoU.il I 'fwAMMI I. J)tJ«1.10».POPMCPt»C»EM(J).NPOPYtIltINOIII
11 FOUU'-M
~ POPT
AC-tT = AOLT
IFI^OP-MP) 611.6ll.911
fell IFIlML'IP.E'J.O) GO TO 912
91Z
OCFS = CEO • XIMl • ACHES
(JUAN a OCFS • T
BOlb = QOAN • IS.O / XOUPM
»t')C = B015 / .«>
O"0 = GUAM • 7.4U / 1000090.0
OACFT = OU&'i / -3SbO.O
CL » *EOC • 7.«.»i • 231.• 16.39 • .001
HfiUH = «.S3.6 • 1000.0
Itt (t.151 NPOr'TCJl .P.PO. AC4ES.CUi'8L
AIA - 0.0
«,t*L = 0.0 -
00 5-0 N=li?l
IFU'JUtNl.EO.l) GO TO T1Z
1.0 '0 713
POP" INI = POPT
AOL*MN> = ACPFT
C'J-''U • C'U.
Al'l'A - AIA
Al'iBU = (AIA • 100.0) / ACRF.T
COMIM'E
If IPOP»"tN» 912.912.913
PO?
OU VI*. 1 = 1.10
NA«'t (1) = NAMMINf I)
CO'll Pint
w-MTF.Ci.l3> CIA»EI P .1 = 1.10)
IOU-4A1 ( IHI. • INHUMATION COVtHING
w^ntcj.su) it
FOWHATIlM .'HtTOHN ttAHS a «.I3//)
01) !<• 1 = 1.*0
»LI'III * o.o
11 >= 0.0
couU» = PO" / ACBES
P = POP
PO » POPOA
IF(PilMH).EO.I) GO TO 71*
= CML • CUWrtL
C'lLAlE I""'EVIUUSN£SS
uo =( <<1.3Z - (b<«.3<>
*•
(0.^309
POPOAM,
A PIP A = A1MPP • ACRES • .01 _ --- .
~ AIA = AtA. A IMP A
C CALCULtlE OUANTITY U FOR THIS ABF.A.
71". CON'TI'flJl •• - - • - ......
APA = ACfLb - *1MPA
CALC»IL«TE POU\OS.COUNTS.MG/L ANO COUNTS/IOO ML.
IF (••C-I <|) Ii9.2-*.21
21 >L^(P = PCMllll • CUtrL
«»i.L.FIO.l
.FlO.l/lH .'PWECIP. UAYa/rx. ••FIO.l
• F10.1/1H .'PU'JCFF CFS 'tFlJ.l
.FlO.l/lH .'UII'JOFF CU. FT.I.FI3.1
.F10.1//I
30
• - I tt l«i.30,
• S f p. . » ' )
31
PAPAHETE»
COEFFICIENTS TOTAL LOAD «CONC.INIT. 1
CNT OB LBS/CM CNT OR LBS MG/L» CNT/1
100
DO
_
59.59.33
33 If (1-6) 3h.34.tO
3« If (I-^>) iD-JbOb
3b w.MLIb.37) I INV ( I . Jl . J= I .b) .PCM1 (P ,X«.B ( 1 1 .XMGL < I)
Jf )0-"4AK1H .bA<..o r>y
• 0 IMI-II) 51. «!.** __ _ _
FORMAT (<0»»NOTWIENTS«»«/)
IF (|-o "NOTE CONC. ASSUMED 90« WASHOFF OF CONTAMINANTS IN 15
•N. •)
. .. 60 CONTINUE _ _ _ _
GO TO VIZ
9t CALL L«1T
H
VO
-------
EXHIBIT 10
BIBLIOGRAPHY - INFORMATION SOURCES
1. "Water Pollution Aspects of Street Surface Contaminants" EPA-R2-72-081,
November 1972, by James D. Sartor and Gail B. Boyd, URS Research Company,
155 Bovet Road, San Mato, California 94402.
?.. "Storm and Combined Sewer Pollution Sources and Abatement - Atlanta,
Georgia" EPA 11024 ELB January 1971, by Black, Crow and Eidsness, Inc.
Consulting Engineers, Atlanta, Georgia.
3. "The Beneficial Use of Storm Water" EPA-R2-73-139 January 1973, by
C. W. Mallory, Hittman Associates, Inc. 9190 Red Branch Road, Columbia,
Maryland 21045.
4. "Enviornmental Assessment - North Fulton County Water Pollution Control
Facilities", by Jordan, Jones and Goulding, Inc. Consulting Engineers,
1655 Tullie Circle, N. E. Atlanta, Georgia 30329, October 1971.
5. "Interim Report on Three Rivers Study Water Quality Management Plan for
City of Atlanta, Atlanta, Georgia" by Black, Crow and Eidsness, Inc.
Engineers, Atlanta, Georgia, May 1973.
6. "Estimation of Imperviousness and Specific Curb Length for Forecasting
Storm Water Quality and Quantity", by Philip H. Graham, Lawrence S.
Costello and Harry J. Mallon, Dept. of Health and Environmental Pro-
tection, Metropolitan Washington Council of Governments, 1225 Connecti-
cut Avenue, Washington, DC 20036, March 20, 1973.
7. "Concrete Pipe Handbook", 1967, by Howard F. Peckworth, American
Concrete Pipe Association, 1815 North Fort Myer Drive, Arlington,
Virginia 22209.
8. "Weather Data Analyses of the University of Georgia College of Agri-
culture Experiment Stations", February 1970 Report 66 by F. L. Crosby,
H. S. Carter, B. H. Quattlebaum, Jr. and Sam Burgess.
9. Municipal Water Works, Weather Bureau Stations at Airports .Consulting
Engineers and Governmental Public Works Departments can supply various
types of historical information.
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