EPA-600/2-76-095
March 1976 Environmental Protection Technology Series
URBAN RUNOFF POLLUTION CONTROL
PROGRAM OVERVIEW: FY '76
Municipal Environmental Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, Ohio 45268
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U S Environmental
Protection Agency, have been grouped into five series. These five broad
categories were established to facilitate further development and application of
environmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The five series are:
1. Environmental Health Effects Research
2. Environmental F'rotection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
This report has been assigned to the ENVIRONMENTAL PROTECTION
TECHNOLOGY series. This series describes research performed to develop and
demonstrate instrumentation, equipment, and methodology to repair or prevent
environmental degradation from point and non-point sources of pollution. This
work provides the new or improved technology required for the control and
treatment of pollution sources to meet environmental quality standards
This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161
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URBAN RUNOFF POLLUTION CONTROL
PROGRAM OVERVIEW FY76
BY
RICHARD FIELD
ANTHONY N. TAFURI
HUGH E. MASTERS
PROGRAM ELEMENT 1BC611
STORM AND COMBINED SEWER SECTION (EDISON, NJ)
WASTEWATER RESEARCH DIVISION
CINCINNATI, OHIO 45268
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' DISCLAIMER
This report has been reviewed by the Municipal Environmental Research
Laboratory, U.S. Environmental Protection Agency, and approved for public-
ation. Mention of trade names or commercial products does not constitute
endorsement or recommendation for use.
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FOREWORD
The Environmental Protection Agency was created because of increasing
public and government concern about the dangers of pollution to the health
and welfare of the American people. Noxious air, foul water, and spoiled
land are tragic testimony to the deterioration of our natural environment.
The complexity of that environment and the interplay between its components
require a concentrated and integrated attack on the problem.
Research and development is that necessary first step in problem
solution and it involves defining the problem, measuring its impact, and
searching for solutions. The Municipal Environmental Research Laboratory
develops new and improved technology and systems for the prevention, treat-
ment, and management of wastewater and solid and hazardous waste pollutant
discharges from municipal and community sources, for the preservation and
treatment of public drinking water supplies, and to minimize the adverse
economic, social, health, and aesthetic effects of pollution. This publi-
cation is one of the products of that research; a most vital communications
link between the researcher and the user community.
The report constitutes a review of EPA's R&D program for Urban Runoff
Pollution Control. It describes completed work, ongoing work and future
work required to abate pollution from wet-weather flows and presents the
overall philosophy of approach to this specific problem as far as EPA's
R&D program sees it.
Francis T. Mayo
Director
Municipal Environmental Research Laboratory
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ABSTRACT
FY'76 review of EPA's Urban Runoff Pollution Control Research, Develop-
ment, and Demonstration ProgramThe review describes the basic problems
associated with urban runoff (both technical and administrative) and the
approach that EPA's R&D program has and is taking to combat these problems.
Information is presented on flood control, erosion control and the basic
pollutional problems created by wet weather flows. Nationwide cost require-
ments for abating urban runoff pollution and available abatement technology
along with ongoing and perceived developments are discussed. Of overlying
importance is the presentation of EPA's research direction and desired goals
oriented toward a truer concept of solution methodolog
Details in summary and abstract form are presented covering the gamut of
technologic advancements resulting from some 150 R&D projects. Stormwater
management is broken down into the categories of: problem definition, user
assistance tools, land management, collection system control, storage, treat-
ment, sludge/solids, integrated systems, and technical assistance/technology
transfer.
General cost comparisons for urban runoff pollution control/treatment are
given along with a specific example of a cost-effective solution for urban
runoff pollution control by in-line storage in Seattle, Washington, and a
simplified hypothetical plan for wet-weather flow pollution abatement for the
Des Moines, Iowa area.
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TABLE OF CONTENTS
PAGE
LIST OF ILLUSTRATIONS vi
SECTIONS
WET-WEATHER FLOW R&D: WHY? 1
PROBLEM 5
APPROACH 8
SOLUTION METHODOLOGY 12
STORM AND COMBINED SEWER PROGRAM 14
MODES OF CONVEYANCE 14
PROBLEM DEFINITION 18
USER ASSISTANCE TOOLS 23
LAND MANAGEMENT 28
COLLECTION SYSTEM CONTROL 34
STORAGE 39
TREATMENT 42
SLUDGE/SOLIDS 45
INTEGRATED SYSTEMS 47
TECHNICAL ASSISTANCE/TECHNOLOGY TRANSFER 51
RUNOFF POLLUTION CONTROL PROGRAM: FY76 54
RUNOFF POLLUTION CONTROL PROGRAM: FY 77 57
CAPITAL COSTS COMPARISONS FOR SCS CONTROL/TREATMENT 59
SEATTLE: IN-LINE STORAGE IS COST-EFFECTIVE 61
DES MOINES: CONTROL COSTS VS. DO VIOLATIONS 63
CONCLUSION 66
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LIST OF ILLUSTRATIONS
NO.
I -
II -
III -
IV -
V -
VI -
VII -
VIII -
IX -
X -
XI -
XII -
XIII -
XIV -
XV -
XVI -
XVII -
XVIII -
XIX -
XX -
XXI -
XXII -
XXIII -
TITLE
WET-WEATHER FLOW R&D: WHY?
POTENTIAL IMPACTS
PROBLEM
APPROACH (SOLUTION METHODOLOGY)
SOLUTION METHODOLOGY
STORM AND COMBINED SEWER PROGRAM (FY'76)
MODES OF CONVEYANCE FOR RUNOFF POLLUTION
SUMMARY: STORM AND COMBINED SEWER PROGRAM
PROBLEM DEFINITION
INSTRUMENTATION FOR TOTAL SYSTEM MANAGEMENT
SIMULATION MODELS FOR TOTAL SYSTEM MANAGEMENT
LAND MANAGEMENT
DEICING CHEMICAL CONTROL (LAND MANAGEMENT/NON-
STRUCTURAL)
COLLECTION SYSTEM CONTROL
SWIRL AND HELICAL DEVICE DEVELOPMENT
STORAGE
TREATMENT
SLUDGE/SOLIDS
INTEGRATED SYSTEMS
SIGNIFICANT DOCUMENTS COMPLETED
SIGNIFICANT DOCUMENTS ANTICIPATED
RUNOFF POLLUTION CONTROL PROGRAM: FY76
RUNOFF POLLUTION CONTROL PROGRAM: FY77
PAGE
2
4
6
9
13
15
16
19
20
24
26
29
33
35
38
40
43
46
48
52
55
56
58
vi
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LIST OF ILLUSTRATIONS
NO. TITLE PAGE
XXIV - TYPICAL CAPITAL COSTS FOR SCS CONTROL/TREATMENT 60
XXV - SEATTLE: IN-LINE STORAGE IS COST-EFFECTIVE 62
XXVI - DES MOINES: CONTROL COSTS VS. VIOLATIONS OF
DO STANDARD (4PPM) 64
vi 1
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WET-WEATHER FLOW R&D: WHY? (Illustration I)
Wet-Weather flow R$D: Why? A larqe portion of the water pollution
load created by urban areas stems from storm-generated discharges.
Representative Concentrations
The average BOD concentration in combined sewer overflow is
approximately one-half the raw sanitary sewage BOD. But storm dis-
charges must be considered in terms of their shock!oading effect
due to their great magnitude. Even separate storm wastewaters are
significant sources of pollution, "typically" characterized as
having solids concentrations equal to or greater than those of
untreated sanitary wastewater, and BOD concentrations approximately
equal to those of secondary effluent. Bacterial contamination
from separate storm wastewaters is also significant.
Representative Loads
(1) From 40% to 80% of the total annual organic loading entering
receiving waters from a city is caused by sources other than
the treatment plant.
(2) Assuming treatment plants are operatinq properly, during a
single storm event, from 94% to 99% of the organic load and
almost all settleable solids are attributed to WWF sources.
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WET-WEATHER FLOW R&D : WHY?
REPRESENTATIVE CONCENTRATIONS
200
200
5x10'
[^1 COMBINED
I | STORM
^^ SECONDARY
IxlO3
TOTAL COLIFORM
MPN/100 ml
REPRESENTATIVE LOADS
40% TO 80% OF TOTAL ANNUAL BOD AND COD ENTERING
RECEIVING WATERS CAUSED BY WET-WEATHER SOURCES OTHER
THAN SECONDARY TREATMENT PLANT
ASSUMING SECONDARY DWF TREATMENT, DURING STORM CONDITIONS
- 94 TO 99% BOD, AND APPROX. 100% SETTLEABLE SOLIDS
FROM CSO, SWD & NSR
- SW MAJOR SOURCE OF PATHOGENS & BACT., & NUTRIENTS
-TOXIC POLLUTANTS, PARTICULARLY HEAVY METALS, HIGH
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(3) The runoff of toxic pollutants, particularly heavy metals, is
high -- considerably higher than typical industrial discharges.
Potential Impacts (Illustration II)
Approximately 1/2 of the stream miles in this country are water
quality limited and 30% of stream lengths are polluted to a
certain degree with urban runoff. Hence, generally speaking,
secondary treatment of DWF is not sufficient to produce required
receiving water quality; and control of runoff pollution becomes
an alternative for maintaining stream standards. Accordingly, both
water quality planning and water pollution abatement programs need
to be based on an analysis of the total urban pollution loads.
Until the urban stormwater situation is analyzed and efficient
corrective measures taken, there is little or no sense in seeking
higher levels of treatment efficiency in existing plants. For
example,
o In Roanoke, VA domestic waste load removal
was upgraded from 86% to 93%, yet there was no dramatic
reduction in the BOD load (3.2 million pounds before
upgrading compared to 3.1 million pounds after.)
o If Durham, NC provided 100% removal of organics and suspended
solids from the raw municipal waste on an annual basis, the
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total reduction of pollutants discharged to the receiving
water would only be 59% of the ultimate BOD, and 5% of
the suspended solids.
These examples are for separate systems; however, communities
with combined systems offer potentially greater pollutional impacts
since additional loads come from domestic wastewaters, dry-
weather sediment wash-out, and more impervious and populated
lands.
PROBLEM (Illustration III)
Recognizing that HWF is a problem, the problem then becomes
"how to approach the solution."
Sewer Separation
The concept of constructing new sanitary sewers to replace
existing combined sewers has largely been abandoned due to
enormous costs, limited abatement effectiveness, inconvenience
to the public, and extended time for implementation. The use
of alternate measures could reduce costs to about one-third the
cost for separation. It is emphasized that sewer separation would
not cope with the runoff pollution load.
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High Costs Implied
However, even in alternate approaches high costs have been
implied. The 1974 Needs Survey identified national costs
for abating combined sewer overflow pollution at $26 billion,
or approximately one-fourth of the total for municipal sewage
control. Similar costs have been indicated from other surveys.
The cost for abating stormwater pollution was estimated at
$235 billion.
There must be a more accurate assessment of the problem
both nationwide and regional to provide the necessary foundation
for policy and law making, and firmer pollution abatement targets --
realistically, can we do a job for the money we have?
Mew R&D Estimates Imply Lower Costs
A project nearing completion gives updated national cost
estimates. For the first time, costs reflected more logical consider-
ations, such as climate and degree of urbanization; pollution abate-
ment of stormwater only and not separate, conventional flood control;
and the fact that storage offers dual benefits of pollutant removal
by settling. Nationally, costs for combined sewer overflow, and
separate stormwater pollution control were $15 billion and $55 billion,
respectively. The major reduction in the national figure for storm-
water control may be attributable to discounting flood control. These
new estimates are not final, and require more review; but the point
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is, we should not shy away from separate stormwater research based
on rough preliminary surveys, if what is required is better estimating
procedures; especially when stormwater pollution is site specific,
and its abatement may be cost-effective in certain areas of the
country.
APPROACH (Illustration IV)
More Accurate Problem Assessment
Considering the limitations in the presently available data
base, the first and most fundamental approach should be a more
accurate assessment of the problem. Ideally, this should involve
acquiring data on a city-wide basis for both DWF and WWF including
upstream-downstream pollutant mass balances and the effects of the
waste loads on the receiving waters.
Cost-Effective Approach
Integrated with a more accurate assessment is the consideration
of cost-effective approaches to WWF pollution control.
Present abatement alternatives exhibit an extraordinary range
of cost-effectiveness. For example, cost-effectiveness in terms of
dollars/lb of pollutant removed for an alternative such as storage
plus primary treatment, varies over a range of 75:1, depending on such
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APPROACH (SOLUTION METHODOLOGY)
MORE ACCURATE PROBLEM ASSESSMENT
- NATIONWIDE/CITY-WIDE
- RECEIVING WATER IMPACTS
- SITE SPECIFIC
CONSIDER ALL COST EFFECTIVE APPROACHES
-COMPARE ALTERNATIVES (SITE SPECIFIC)
o TERTIARY VS. WWF CONSIDERATIONS
o STRUCTURAL VS. LAND MGMT. &
NON-STRUCTURAL
o INTEGRATED DWF/WWF SYSTEMS
-INTEGRATE FLOOD/EROSION CONTROL TECH.
WITH POLLUTION CONTROL TECH.
- INTEGRATE LAND MANAGEMENT AND
NON-STRUCTURAL TECHNIQUES
OVERCOME ADMINISTRATIVE PROBLEMS
- LOGISTICS
- GRANT COVERAGE
IV
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factors as location and land costs, type and condition of sewerage
systems, pollution loads, and type of storage configuration. This
very high cost-effectiveness variability demonstrates the irration-
ality of any attempt to prescribe uniform national standards for the
technology of total urban load abatement as opposed to requiring
site-specific studies.
There is an excellent opportunity to bring down the high costs
implied for storm flow control.
The most cost-effective solution methodology must thoroughly
consider:
1. Wet weather pollution impacts in lieu of blindly upgrading
existing municipal plants.
2. Structural vs. land management and non-structural techniques,
Studies have indicated that it may be cheaper to remove
pollutants from the source by such measures as street,
catch basin, and sewer cleaning than by eliminating them
by downstream treatment. Certain land use, zoning, and
construction site erosion control practices are other
ways of alleviating the solids burden to the receiving
stream or treatment plant; and
10
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3. Integrating dry and wet-weather flow systems to make maximum
use of the existing sewerage system during wet conditions
and also maximize the utilization of wet-weather control/
treatment facilities during dry weather.
Until two important philosophies are allowed to prevail, the high
cost implications for wet-weather pollution abatement will continue.
First, flood and erosion control technology must be integrated with
pollution control technology so that the retention and drainage
facilities required for flood and erosion control can be simultaneously
designed for integrated dual-benefits of pollution control. Second,
if we maximize and integrate land management and non-structural
techniques there will be less to pay, for the extraction of pollutants
from storm flows in the potentially more costly downstream plants.
Overcome Administrative Problems
It is essential to include these concepts if we are to handle
the job properly. But, there are basic problems in administration
that have to be overcome.
Logistics -- we have to integrate the autonomous Federal and
local agencies and professions involved in flood and erosion
control, pollution control, and land management and environ-
mental planning from the standpoints of both planning and
operation.
11
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Grant Coverage - must be adequate to stimulate an integrated
approach. For example, EPA would have to join with the
Corps, Soil Conservation Service, and perhaps other agencies
at the Federal level as well as departments of pollution
control, sanitation, planning and flood control at the
local level. EPA's present policy of funding facilities
construction will need expansion to cover cost-effective
land management and non-structural techniques promulgated
by its planning grant approach.
SOLUTION METHODOLOGY (Illustration V)
I will attempt to show one approach to cost-effective solution
methodology on a hypothetical basis. These curves represent percentages
of time receiving water D.O. is greater than or equal to a D.O. level
of the abscissa. They should represent at least one year's
continuous flow of data. This case is for D.O. but actual
studies should include other parameters. By this analysis
we can make true cost-effectiveness comparisons based on total
time of receiving water impacts and associated abatement costs. For
example, if we desire 5 mg/1 D.O. in the receiving water
75% of the time as a standard, then we need to go to an advanced
form of wet-weather treatment, or primary wet-weather treatment
integrated with land management. The latter is the most cost-
effective at $3M. This; or similar methodologies can help
us set cost-effective standards as well as select alternatives.
12
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SOLUTION METHODOLOGY
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STORM AND COMBINED SEWER PROGRAM (Illustration VI)
This schematic portrays the Storm and Combined Sewer Program
breakdown for FY 76. The objective is Runoff Pollution Control
which has three sub-objectives: (1) Combined Sewer Pollution Control,
(2) Sewered and Unsewered Runoff Pollution Control, and (3) Hydrologic
Modification.
MODES OF CONVEYANCE (Illustration VII)
In formulating a programmatic approach for runoff pollution
control we feel it is advantageous to look at the problem from the
point of view of modes of conveyance: i.e.
- combined sewers
- infiltrated sanitary sewers
- storm sewers, arid
- unsewered runoff
Hydrologic modifications considers control technology for
such activities as construction, dredging, landfill, and water
resources development. It does not logically fit into the
"modes-of-conveyance" approach to runoff pollution control. The
effects of hydro!ogic modifications are felt in combined sewers, storm
sewers and unsewered runoff and the technology for sediment/erosion
control and pollutant/flood control must be integrated for stormwater.
In fact, the program has always considered silt-laden stormwater from
construction as a constituent and source of pollution.
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Hence it makes more sense to break the program into two
major areas:
- Combined Sewer Pollution Control covering combined
sewers and infiltrated sanitary sewers, and
- Sewered and Unsewered Runoff Pollution Control
covering storm sewers, unsewered runoff, and
hydro!ogic modifications.
In formulating an approach methodology it is also advantageous
to recognize the similarities between these two areas. The charac-
terization of the combined sewer overflow and stormwater problems
is similar, for it is merely a qualification and quantification of
storm flow independent of the sanitary constituent. The same
instruments or users assistance tools are applied to combined
sewer overflow and stormwater. Land management and non-structural
pollutant source removal techniques are the same, independent of
whether the runoff enters a combined or separate system. The
control or treatment hardware although mainly developed for
combined sewer overflow has high trade-off potential for stormwater.
The basic philosophy in applying countermeasures or solution
methodology is also independent of the mode-of-conveyance.
Also, all communities have intermingled systems; i.e.,
sanitary sewers discharging into storm drains, storm drainage going
into sanitary lines via infiltration/inflow, or sanitary sewers
discharging into combined sewers, and vice versa.
17
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Accordingly, the Runoff Pollution Control Program as I will
present it today will be divided into the following technical areas
of consideration, common to both major elements, Combined Sewer
Overflow Pollution Control, and Sewered and Unsewered Runoff Pollu-
tion Control: Problem Definition, User Assistance Tools (Instru-
mentation, Computers), Land Management, Collection System Control,
Storage, Treatment, Sludge and Solids, Integrated Systems, and
Technical Assistance and Technology Transfer.
Please refer to Illustration VIII of your handout which ties
the categories together for a complete picture while I discuss
each category individually with the help of visual aids. There have
been many projects under the program -- about 150, so I only have
time to highlight a basic program direction by citing significant
completed and ongoing work, present fiscal year and future tasks.
PROBLEM DEFINITION (Illustration IX)
The program starts with "Problem Definition" broken into
"Characterization" and "Solution Methodology."
Characterization
Under "Characterization" the S&CS Program started as a result
of the original PHS problem study completed in 1964. Since then
more detailed appraisals confirmed the problem. Past characteriza-
tion studies for storm flow give a data base for pollutant source
18
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accumulation and hydraulic loads. With these loads, resultant
receiving water impact analyses further defined the problem.
A total data base and retrieval system is being developed by separate
contract. Special characterization studies were carried out
for deicing salt, sediment/erosion, and pathogenic impacts from
storm flows. The importance of a more refined nationwide wet-
weather pollution impact and abatement cost study was previously
mentioned.
Solution Methodology
Solution Methodology naturally followed initial characteri-
zation for providing uniform and necessary background for the
user community. Highlights, are the often referenced SOTA's on
storm flow measuring and sampling, along with those for deicing
and erosion control.
Eight separate city studies each on an economic comparison of
pollution control alternatives portrayed various concepts and the
municipal approach. The recently completed text on urban stormwater
management and technology is considered an excellent program milestone
and guide for planners and engineers. It is being updated and
will cover comprehensive guidance for total city-wide, wet-weather
pollution control planning and countermeasure selection. Separate
engineering manuals for urban storm flow and volume determination,
and for the conduct of stormwater studies have just been completed.
21
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These along with the other solution methodology documents are
serving for 201 and 208 studies. A city-wide demonstration on multi-
faceted approach methodology is being conducted in Rochester to serve
as an example for other cities.
This fiscal year we are endeavoring to study direct receiving
water impacts, along with further development of source loading
factors (and verification of a water quality model). This project
will serve as an important demonstration by lending credence to
the implications of storm flow impacts. We are currently in the
process of selecting a demonstration project, with a possibility
of riding piggy-back under 201 and 208 projects in Milwaukee,
Philadelphia, or Syracuse. We have also included receiving water
impacts in an ongoing project in Lancaster, PA and received
additional non-EPA funds to conduct a receiving water impact
analysis for the ongoing Rochester project. It is felt that more
than the $165K slated for impacts will be required by next year
because of the complex sampling and analysis, and multi-site
coverage necessary to meet our objectives.
Dr. Brunner has previously introduced our present in-house
study on an analysis to optimize wet and dry-weather flow treatment
and control combinations. This work will also help develop an in-
house strategy document this fiscal year.
22
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In FY 78 we would like to initiate an assessment of the various
201 and 208 planning grants, and later a refined manual on solution
methodology culminating our objectives in the area of problem
definition.
USER ASSISTANCE TOOLS
User Assistance Tools: the category is divided into "Instrumen-
tation" and "Simulation Models."
Instrumentation (Illustration X)
The qualitative and quantitative measurement of storm overflows
is essential for process design, control, evaluation, and enforcement.
"Urban intelligence systems" require real-time data from rapid
remote sensors in order to achieve remote control of a sewerage network.
Sampling devices do not provide representative aliquots, and in-line
measurement of suspended solids and organics is needed.
The electromagnetic, ultra-sound, and passive sound flowmeters
which have been developed and demonstrated overcome adverse storm
flow conditions (which require dual pressure-gravity measurement of
unsteady flows by non-intrusive instrumentation). Further demonstra-
tion of the electromagnetic flowmeter will take place this fiscal
year by a contract continuation. A prototype sampler for capturing
representative solids in storm flow, and overcoming storm flow
23
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adversities, has been developed and compared with conventional samplers.
Favorable results have been obtained and a design manual is available.
Demonstration of two previously developed rapid, in situ monitoring
devices for suspended solids and TOC is nearing completion. Pre-
liminary tests have been successful. In FY 76 part of a continuation
for a demonstration grant in Syracuse includes additional verifica-
tion of the sampler and TOC analyzer.
Separate SOTA reports for flow measurement and sampling
have been mentioned under problem definition.
The instrumentation effort seems to be coming to a head, but
before that, it would prevail upon us to reactivate our full size
test loop in the possession of FMC for further testing of S&CS
program developed, and other instrumentation.
(Remote raingaging by radar; and optimization of control gates
to enhance automatic flow routing, a need coming out of the EPA
Clemson University Instrumentation and Automation Seminar, will
be considered for future projects.)
Simulation Models (Illustration XI)
Math models are needed to predict complex dynamic responses
to variable and stochastic climatological phenomena. Models
have been subcategorized into three groups: (1) simplified
25
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for preliminary planning, (2) detailed for planning and design,
and (3) operational for supervisory control.
We have demonstrated the benefits of the Storm Water Manage-
ment Model, SWMM, for detailed planning and design. As the
schematic shows, SWMM is being augmented to include natural
drainage routing and integration of DWF facilities. WWF sludge
quantification and handling will be incorporated this fiscal
year by a grant continuation.
A simplified SWMM model has just been developed which can run
continuously on a year's data, on hourly time steps to cover wet and
dry-weather periods and allow for continuous receiving water impact
analyses. A more simple model with only a few hundred statements
has been developed for alternative control screening (by M&E) under
the Rochester project. This model is being tied together with
SWMM to demonstrate a cost and time saving modeling approach
for city-wide master plan development.
We would like to end the modeling program with the Urban
Water Management Model (UWMM) by expanding SWMM to include the
needed concepts of reuse, and receiving water and water use economics,
There is a defined program for operational models. We have
demonstrated supervisory control models in Detroit, St. Paul, and
Seattle; and have recently started on a program in San Francisco
riding piggy-back with a $100 million construction grant, to
27
-------
develop a fully automated operational model which includes rainfall
prediction. The total EPA R&D cost is $195K, of which $130K is being
awarded this fiscal year.
The technical dissemination program for models includes users
manuals, revised at critical junctures, and technology transfer
previously set up under a grant to the University City Science
Center, and three short courses and manuals conducted and prepared
under another continuing grant.
LAND MANAGEMENT (Illustration XII)
The next category, "Land Management" is broken into
"Structural" and "Non-Structural" controls.
"Land Management" includes all measures for reducing storm-
water pollution before urban runoff enters the sewer system. In-
cluded, are measures that affect both the quantity and quality of
urban runoff.
Structural
Conventional flow control measures, mostly "structural" in
nature, include upstream earthen impoundment, and sediment and
erosion control. Other forms of upstream detention include roof-
top storage and temporary use of recreational lands. New concepts,
28
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such as porous pavement and the integration of flood with pollution
control technology should also be included. By temporarily detaining
runoff upstream, drainage can be reduced, resulting in less flow to
store and treat downstream. If this is coupled with retaining runoff
from pervious areas for percolation into the ground, then the total
volume of water entering the drainage system is reduced. Hence,
considerable savings in both operation and initial construction
costs will result.
During this fiscal year it is anticipated that funds will be
used to continue an evaluation of sediment and erosion control
techniques. Future projects should provide a series of handbooks.
Non-Structural
Quality control measures are mostly "non-structural," and in-
clude housekeeping or surface sanitation, chemical use restriction,
air pollution control, and careful consideration of land use,
development and zoning. Certain sediment and erosion control
measures, such as cropping and berming may be considered non-
structural .
Previous studies have shown the water pollution aspects of
street surface contaminants and the importance of good neighborhood
sanitation practices. Significant amounts of toxic substances
were detected in the finer fraction of street dust and dirt.
30
-------
Conventional street sweepers are inefficient in removing this
fraction indicating a need for improved street cleaning equipment.
Our program is planning a surface sanitation demonstration project
this fiscal year or during FY 77.
Deicing chemicals will be mentioned later.
Careful consideration must be given to land use planning. --
Urbanization accelerates hydrograph and pollutograph peaks by
creating impervious surfaces for pollutants and water to run off
from. Future projects should be concerned with optimizing land
use and resultant cost effectiveness. As previously discussed,
the use of natural drainage concepts reduces drainage costs, enhances
aesthetics and flood protection, and lowers pollution. Our new
town development project near Houston is providing coverage in
this area.
Future work should continue to demonstrate improved land manage-
ment and surface cleaning practices for pollution reduction including
air pollution aspects. We are presently trying to recruit
interest from EPA air pollution research on our proposed project to
demonstrate water and air quality benefits from street cleaning.
Your help in this effort will be appreciated. Manuals of practice
must be obtained in all areas of land management.
31
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Deicing Chemical Control (Illustration XIII)
Until the SCS Program's SOTA report in 1971 there had been
only limited research on highway deicing effects. Inquiries con-
cerning this work indicated such an increasing public awareness of
the salt problem, that it seemed appropriate to reexamine the environ-
mental issues in much greater depth. The resulting recommendations
firmed the basis for further salt work.
During 1972, a search was conducted to define alternatives for
ice control. The results indicated the need for an accurate cost-
benefit analysis of alternative approaches, and a requirement to
identify a substance which can be applied to pavement to reduce
ice adhesion. These two needs became projects, both nearing completion.
During this fiscal year optimization and demonstration of an icephobic
substance (organo-silicone, Dow Corning DRI-SIL 73) is anticipated.
Even though material and application costs of this new substance
appear greater than salt, the economic analysis has indicated that
when considering total damage to the environment (including paved
areas, highway structures and vehicles) the costs are acceptable.
After the 1971 SOTA, the program recognized that it was not
practical to ban salt since the "bare pavement" philosophy was very
popular and considered by many highway authorities as the safest
way for ice and snow removal. Since the major problems were identified
with sloppy salt storage practices and over-application on highways
a contract was awarded in 1974 to produce manuals of practice in
32
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these areas. These manuals became available in 1975 and recognizing
their value and popularity, the FHWA requested permission to reprint
the manuals for their own distribution.
It is believed that the outcome of our work has prompted
several states to enact legislation controlling the application and
storage of salt. In the future we hope to verify the cost-effectiveness
of an icephobic substance and demonstrate full-scale innovative snow
and ice removal techniques.
COLLECTION SYSTEM CONTROLS (Illustration XIV)
The next category., collection system control, pertains to
those management alternatives concerned with wastewater interception
and transport. These alternatives include sewer separation; improved
maintenance and design of catch basins, sewers, regulators and tide
gates; and remote flow monitoring and control. The emphasis, with
the exception of sewer separation, is on optimal utilization of the
existing facilities and fully automated control. To accomplish
this an extensive and dependable intelligence system is necessary.
Catch Basins
An ongoing project is assessing the value of catch basins
as they are presently designed and maintained. Optimized design and
maintenance for removing solids before sewerage system entry is also
being investigated.
34
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Sewers
Solids deposition in lines has always been a plague to effec-
tive maintenance. Recently the significance of such loads as a
major contributor to first flush pollution has been recognized.
Work is being conducted on new sewer designs for low flow
solids carrying velocity to alleviate sewer sedimentation and
resultant first flush and premature bypassing; and also on sewer
designs for added storage. During this fiscal year or during
FY 77, we anticipate a project to demonstrate periodic sewer
flushing, also for first flush relief.
Flow Routing
An ongoing project mentioned earlier with the Cith of San
Francisco is developing an automatic operational model for real-
time control. Future demonstration of the system is anticipated.
A serious problem results from infiltration and inflow and
has been well defined and countermeasures developed in previous
program studies. We are currently conducting a project to develop
practices for determining infiltration and its economic analysis.
During the current fiscal year we plan to sponsor further studies
to evaluate strength increases and erosion resistance from sulfur
impregnation of concrete pipe. Since pipe costs are significant in
36
-------
construction grants, an increase in strength could lead to a
decrease in pipe materials and construction costs.
Regulators and Tide Gates
Conventional regulators and tide gates malfunction and cause
excessive overflows and backwater entry to the sewerage system.
The new improved devices such as fluidic and positive control
regulators have been developed and demonstrated. The swirl and
helical devices are significant enough to single out on a separate
illustration.
Swirl and Helical Device Development (Illustration XV)
The dual functioning swirl device showed outstanding potential
for providing both quality and quantity control. The device re-
quires no moving parts, thus eliminating power costs and O&M problems,
It is a small, ultra-high rate device of simple construction that
can take the place of the inefficient conventional flow control
regulators. In conjunction with its ability to control flows, the
device can treat solids effectively at highly varying overflow rates.
In 1971 the SOTA report on regulators suggested a British
device using vortex flow patterns could regulate flow and
simultaneously remove solids. Based on this concept a hydraulic
model investigation by the Program during 1972-1973 produced a
37
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universal design being successfully demonstrated in Syracuse; and
now being employed for a large-scale demonstration in Lancaster, PA
Also during 1973-1974 model development was conducted to formulate
swirls for degritting and primary clarification. During 1975,
pilot studies were conducted in Denver on the swirl degritter, and
in Toronto on the swirl clarifier. Evaluations are proving satis-
factory from both sites. These solids separation devices have
high trade-off potential for other M&I flows. Development of the
swirl concept for erosion control has just been completed. It is
hoped that full-scale demonstrations of the degritter, clarifier,
and erosion control device will be conducted and that complete
technology transfer documentation on the swirl concept will be
implemented.
The 1971 regulator SOTA also lead to the development of a
helical flow regulator/solid separator. A comparison of a full-
scale swirl and helical regulator is anticipated.
STORAGE (Illustration XVI)
Storage is perhaps the most cost-effective method available
for reducing pollution resulting from combined sewer overflows
and managing urban stormwater runoff. Furthermore, it is the best
documented abatement measure in present practice. (Storage, with
the resulting sedimentation that occurs, can also be thought of as
a treatment process.)
39
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Storage facilities possess many of the favorable attributes
desired in storm flow control: (1) they are basically simple
in structural design and operation; (2) they respond without
difficulty to intermittent and random storm behavior; (3) they are
relatively unaffected by flow and quality changes; and (4) they
are capable of providing flow equalization and, in the case of
sewers and tunnels, transmission. (Frequently they can be operated
in concert with regional dry-weather flow treatment plants for
benefits during both dry- and wet-weather conditions.) Finally,
storage facilities are relatively fail-safe and adapt well to
stage construction.
Storage facilities may be constructed in-line or off-line;
they may be open or closed; they may be constructed inland and
upstream, or on the shoreline; they may have auxiliary functions,
such as flood protection, sewer relief, and flow transmission.
(And they may be used for hazardous spill containment during
dry weather.)
Storage concepts investigated by the program include concrete
holding tanks, earthen basins, tunnels, underground and underwater
containers, underground "silos," gravel packed beds with overhead
construction, natural and mined under and above ground formations,
and the use of abandoned facilities and existing sewer lines.
41
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Inherent in many of these storage schemes is the pumping/bleeding
back of the stored flow to the DWF plant during off-peak hours.
The impacts of this increased load on the DWF plant (both from a
hydraulic and increased solids point of view) is an important
consideration and is presently being investigated in an ongoing
project (Envirex). Once this impact information is available
we feel we could summarize the SOTA in the form of a design manual
(Post FY 77).
The feasibility of off-line storage and deep tunnel storage
along waterways for selective discharge based on least receiving
water impacts is presently being investigated in Rochester. This
concept along with dual DWF and WWF storage, will be demonstrated
in our post FY 76 plans as part of a tie-in to Construction Grants.
Future program plans include the investigation of new storage
configurations, such as floating storage facilities, cofferdams,
storage under piers, etc. Full-scale demonstration of some of the
more promising configurations, e.g., silos and underwater bags, is
also desirable.
TREATMENT (Illustration XVII)
Due to adverse flow conditions and unpredictable shock loading
effects, it has been difficult to adapt existing treatment methods
to storm-generated overflows, especially the microorganism depend-
ent biological processes. The newer physical/chemical treatment
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techniques have shown more promise in overcoming these adversities.
To reduce capital investments, projects have been directed towards
high-rate operations approaching maximum loading boundaries.
Applications include pretreatment or roughing, main or sole treat-
ment, and particularly with micro-strainers and filters, polishing
devices.
This fiscal year we will invest in a grant continuation to
further compare three different fine screens for combined sewer over-
flow treatment. In the near future, if money permits, we would
like to implement a full-scale swirl primary treatment demonstration,
Physical/Chemical Treatment
Physical processes with or without chemicals, such as: fine
screens, swirl primary and swirl degritters, high-rate filters,
sedimentation, and dissolved air flotation, have been developed
and demonstrated by the program. Ammonia removal and an advanced
physical-chemical-adsorption system have also been developed and
tested at the pilot level. Physical processes have shown importance
for stormwater treatment because of their adaptability to automated
operation, rapid startup and shut-down characteristics, high-rate
operation, and very good resistance to shock loads.
Land Disposal
We are presently demonstrating the use of marshlands for dis-
44
-------
posal of stormwater in Minnesota, and are about to embark on a
feasibility study of land disposal for combined sewage and storm-
water. If land disposal proves feasible, our next steps will be
an actual controlled demonstration.
Biological Treatment
The following biological processes have been demonstrated: con-
tact stabilization, high-rate trickling filtration, rotating biolo-
gical contactors, and lagoons. The first three have had positive
evaluation, but must operate conjunctively with DWF plants to
supply biomass, and require some form of flow equalization.
Disinfection
Because disinfectant and contact demands are great for storm
flows, research has centered on high-rate applications by mixing
and more rapid oxidants, i.e., ClO^ and CL; and on-site generation.
Because of new concerns, a grant supplement this fiscal year
will allow viral disinfection and carcinogenic chlorine residual
compound studies tied onto a full-scale demonstration in Syracuse.
SLUDGE/SOLIDS (Illustration XVIII)
Due to the documented deleterious effect of CSO on the quality
of receiving waters, WWF sludge handling and disposal has been held-
off in concession to the problems of treating the combined over-
45
-------
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flow itself. Sludge handling and disposal should be considered an
integral part of CSO treatment because it significantly affects
the efficiency and cost of the total waste treatment system.. Flow
characterization studies show that the annual tonnage of WWF solids
is at least equal to and in most cases greater than solids from DWF.
The Program recognized the need for defining the problem and,
in FY 73, awarded a contract to characterize and preliminarily
quantify wet-weather flow sludge and solids and perform treatability
studies. Follow-up work will evaluate pilot-scale thickem'ng-
centrifugation, and bench-scale anerobic digestion. During FY 76
alternative sludge handling/disposal techniques will be evaluated
and a nationwide assessment of the sludge problem will be conducted.
As part of this assessment, the "impacts" of returning WWF sludges
and solids to the DWF plant and the need to classify grit from organics
will be evaluated. In the future we would like to demonstrate land
disposal of WWF sludges and investigate new techniques, such as the
use of the swirl device for sludge thickening.
INTEGRATED SYSTEMS (Illustration XIX)
By far the most promising and common approaches to urban
stormwater management involve the integrated use of control and
treatment with an areawide multidisciplinary perspective. When a
single method is not likely to produce the best possible answer to
47
-------
INTEGRATED SYSTEMS
PRE-FY76
FUTURE
STORAGE/
TREAT
DUAL USE,
WWF/DWF
FAC
DEM. STORAGE W/
PUMP-BACK
SED. IN STORAGE
STORAGE/TREAT LAGOON
DISINF.
BREAK-EVEN ECON.
W/TREAT
DEM. TREAT
HRTF (F/S)
CONT STAB (F/S)
HI-RATE FILT(F/S)
P-C(AWT,PILOT)
DEM. EQUALIZATION
(ROHNERT PK.)
COMBINED SEWERS
DEM. TREAT
PHY-BIOL
DISS AIR FLOT
MICROSCREENS
DEM. STORAGE
DWF/WWF
W/EFFL POLISH
CONT/TREAT/
REUSE
LAND MGMT/TREAT
TREAT-PK
STORAGE-TREAT
LAKELETS
DEM. STOR-TREAT-
RECHARGE
48
XIX
-------
a given pollution situation, various treatment and control measures
may be combined for maximum flexibility and efficiency.
Integrated systems is divided into (1) Storage/Treatment,
(2) Dual Use WWF and DWF Facilities, and (3) Control/Treatment/Reuse.
Storage/Treatment
Where there is storage, there is treatment by settling, pumpback
to the municipal works, and sometimes disinfection; and treatment,
which receives detention, provides storage. In any case, the break-
even economics of supplying storage must be evaluated when treatment
is considered. The program has demonstrated all of these storage-
treatment concepts on a full-scale basis.
Dual Use. WWF/DWF Facilities
The concept of dual use is -- maximum utilization of wet-weather
facilities during nonstorm periods and maximum utilization of dry-
weather facilities during storm flows for total system effectiveness.
The program has demonstrated the dual use of high-rate trickling
filters, contact stabilization, and equalization basins. On a
pilot scale we have evaluated dual-use advanced physical-chemical
treatment; and we are in the process of demonstrating large-scale,
high-rate filtration.
49
-------
In Fiscal Year 77 we are planning to investigate the dual use
potential of dissolved air flotation at our existing Milwaukee pilot
by determining design and operation for DWF for the establishment
of joint WWF/DWF criteria and a manual. Another FY 77 planned
project will evaluate the use of a sedimentation-activated sludge
system for DWF, switched to a high-rate, dissolved air flotation-
contact stabilization system for WW from highly infiltrated sanitary
sewers in Clatskanie, Oregon. The same tanks will be used for both
wet and dry-weather operations. Hopefully, in FY 77 we will also be
able to evaluate the dual-use of microscreens for raw CSO treatment
and DWF secondary effluent polishing. It is anticipated that ORD can
ride piggy-back on Construction Grants again, for both the Clatskanie
and the microscreening projects.
In the future it is important to evaluate triple-use storage for
DWF and WWF along with secondary effluent polishing.
It should also be mentioned that combined sewers themselves are
dual use systems.
Control/Treatment/Reuse
The sub-category, "Control/Treatment/Reuse" is a "catch-all"
for all integrated systems. As the prime consideration, it is
reasonable to apply the various non-structural and land management
techniques to reduce downstream loads and treatment costs.
50
-------
Various studies and a demonstration have indicated the feasibility
of the treatment-park concept. In Mt. Clemens, MI, a series of
three "lakelets" has been incorporated into a park development. Treat-
ment is being provided so that these lakes are esthetically pleasing
and allow for recreation and reuse for irrigation.
The project in Houston focuses on how a "natural drainage
system" can be integrated into a reuse scheme for recreation
and aesthetics. Good land use management will allow runoff to
flow through low vegetated swales and into a network of wet-
weather ponds, strategically located in areas of porous soils.
This system will cause some of the runoff to seep into the ground
and retard the flow of water downstream, thus preventing floods
caused by development and enhancing pollution abatement. The
concept of considering urban runoff as a benefit as opposed to a
wastewater, in a new community development, will be employed and
evaluated.
TECHNICAL ASSISTANCE/TECHNOLOGY TRANSFER (Illustration XX)
The final program area of consideration is concerned with
"Technical Assistance" and "Technology Transfer." Within the
Technical Assistance category are such items as consultation to
Federal, state, local, and foreign governments; participation in
national and international conferences and seminars; and response
to public information requests. In the past few years technical
51
-------
SIGNIFICANT DOCUMENTS COMPLETED
1. ASSESSMENT - PROBLEMS OF CSO/SW
2. CSO SEMINAR REPORTS
3. MOP - I/I PREVENTION & CORRECTION
4. MOP - REGULATION & MGMT
5. DESIGN MANUALS - SWIRL: REGULATOR/DEGRITTER/EROS. CONTROL
6. DESIGN MANUAL - HELICAL REGULATOR/SEPARATOR
7. ASSESSMENTS - SOURCES/IMPACTS OF URBAN RUNOFF POLLUTION
8. ASSESSMENTS - SAMPLING/FLOWRATE MEASUREMENT
9. ASSESSMENT - IMPACT OF DEICING
10. MOP'S - DEICING CHEMICAL USAGE/STORAGE & HANDLING
11. ASSESSMENT - SOTA URBAN SW MGMT & TECHNOLOGY
12. USERS MANUALS - SWMM, VERSION I & II
13. COURSE MANUAL - SWMM APPLICATION
14. MOP - DETERMINATION OF FLOWRATES/VOLUMES
15. ASSESSMENT/MOP - STORMWATER MODELS
16. MOP - PROCEDURES FOR SW CHARC./TMT STUDIES
17. MOP - SEDIMENT & EROSION CONTROL
5? XX
-------
assistance has occupied 20% of program time. While the areas of
consideration within technical assistance may change somewhat, it
is anticipated that this level of effort will grow; especially
with the increased emphasis on 208/201 planning in the wet-weather
flow area. Requests in these areas are demanding much more of an
involvement than in the past. We are being asked to review more
grant applications and documents, and lecture more frequently for
EPA Headquarters and the Regions.
The Technology Transfer area covers the formal dissemination
of program findings in the form of actual project reports, films,
journal papers, SOTA reports, and manuals of practice and instruction,
To date we have published approximately 125 reports, and it is the
intent here to concentrate on the "user" type of document.
Significant Documents Completed
Reports generated by the program have received widespread
recognition both within this country and abroad. Many have been
referenced by EPA Headquarters and used for 201/208 studies. I'd
like to highlight some. The first reports, Item No. 1, set the
pace for EPA's program by identifying stormwater and combined
sewer overflow as major sources of water pollution. Our manuals
of practice on infiltration/inflow and regulators, Nos. 3 and 4,
flagged two prime and basic problems leading to fruitful counter-
measure research and a national emphasis on I/I control. Specific
53
-------
research products coming out of the regulator MOP were the swirl
and helical devices -- resultant design manuals are listed as
Nos. 5 and 6. No. 8 sites two instrumentation reports for flow
analysis which have proven to be highly useful to the engineering
community, including Construction Grants. Report Nos. 11 through
17 relate to Approach and Solution Methodology, the goal of the program.
Significant Documents Anticipated (Illustration XXI)
In the immediate future, we will be releasing the previously
mentioned national assessment document, and a refined SWMM users
manual; along with two other assessments: one on the WWF sludge
handling and disposal problem, and the other on pathogens in storm-
water.
Ongoing work will also lead to an updated SOTA and a planning
document providing guidance and examples for total municipal studies.
(Other significant documents anticipated from ongoing projects
are listed, along with some major documents from anticipated
"Post FY 76" work.)
RUNOFF POLLUTION CONTROL: FY 76 (Illustration XXII)
This table summarizes the FY 76 projects, associated costs, and
their status. Our total extramural budget is $800K. I am not
taking time to reiterate each since they were previously mentioned
in the context of how they fitted into our development plans. What
54
-------
SIGNIFICANT DOCUMENTS ANTICIPATED
FY 76
ASSESSMENT - NATIONWIDE SW/CSO CHARACTERIZATION/IMPACTS/COSTS
USERS MANUAL - SWMM VERSION III
ASSESSMENT - WWF SLUDGE HANDLING/DISPOSAL PROBLEMS/IMPACTS
ASSESSMENT - PATHOGENS IN SW & CSO
SOTA/PLAN. GUIDE - UPDATE S&CSO MGMT & TMT/TOT APPROACH METH
DESIGN MANUAL - SWIRL: PRIMARY TMT
SOTA - URBAN WATER MANAGEMENT MODELING
MOP - I/I ANALYSIS, PREVENTION & CONTROL
INSTRUCTION MANUAL - S&CSO TECHNOLOGY
POST FY 76
MOP - POLLUTION CONTROL FROM CONSTRUCTION ACTIVITIES
MOP - REFINED SOLUTION METHODOLOGY
MOP - LAND MANAGEMENT
DESIGN MANUAL - STORAGE FACILITIES
CONSOLIDATED DESIGN TEXT - SWIRL & HELICAL
55
XXI
-------
RUNOFF POLLUTION CONTROL PROGRAM: FY 76
SO: COMBINED SEWER POLLUTION CONTROL
DEMO NON-STRUCTURAL SOURCE CONTROL; ST CL EAN I NG/ FLUSH I NG
DEMO AUTO CONTROL OF CS SYS (CONT S-803743, SAN FRAN)
INCORP SLUDGE TREAT OPT PROG INTO SWMM USER'S MANUAL
(AMEND 802411 , UNIV OF FL)
FIELD EVAL OF AUTO SAMPLER, IN SITU TOC ANALYZER, ADD
DISINF STUDIES (CONT S-802400, ONONDAGA CO.)
EVAL ALTERNATIVES FOR ULTIMATE DISPOSAL OF RAW/TREATED WW
SOLIDS AND EVAL FEAS OF LAND DISPOSAL OF RAW CSO/SW
(CONT 68-03-0242 ENVIREX)
EVAL STRENGTH IMPROVEMENT OF IMPREGNATED CONCRETE PIPE
(AMEND 802651, TEXAS WATER QUALITY BOARD)
EVAL ELECTROMAGNETIC FLOWMETER FOR S&CSO APPLICATION
(CONT 68-03-0341, GUSHING ENGR)
TRANSLATION OF FOREIGN REPORTS FOR SOTA UPDATE
(AMEND 68-03-2228, M&E)
COMMITTED OVERRUNS
SO: SEWERED & UN-SEWERED POLLUTION CONTROL
F/S DEMO OF HYDROPHOBIC/ICEPHOBIC MATERIAL TO MITIGATE
ICE ADHESION (CONT 68-03-0359, BALL BROS RES CORP)
EVAL EFF OF OFF-STREAM DET-RET MEASURES AS SEDIMENT
CONTROL DEVICES (CONT R-803066-01, HOWARD UNIV)
SWR RECEIVING WATER IMPACT ANALYS I S/ POLL UTANT LOADING
DETERMINATIONS
DET VOLUMES AND FLOW RATES FOR STEEP SLOPE SEWERS
(AMEND 68-03-0302, UNIV OF ILL)
SO: HYDROLOGIC MODIFICATION
DEMO SEDIMENT/EROSION CONTROL TECHNIQUES (CONT S-803724,
UNIV OF SOUTH CAROLINA)
TOTAL FY 76 RESOURCES
$K
124
130
43
80
30
30
32
7
9
40
11
186
7
70
799
STATUS
PROPOSALS UNDER REV/
SAN JOSE, APWA/CINN/BOS.
BEING PROCESSED
PROCESSED
BEING PROCESSED
BEING PROCESSED
BEING PROCESSED
PROCESSED
PROCESSED
PROCESSED
BEING PROCESSED
BEING PROCESSED
MILW (PRE-PROPOSAL)/
PHI LA/ SYRACUSE/ PATTERS ON/
F I TCHBURG/ HOUSTON/ RICH/
ATLANTA
PROCESSED
UNDER REVIEW
XXII
-------
I would like to point out, is that all line item proposals have been
received, and a number have been processed. In other words, we are
in good shape this year!
RUNOFF POLLUTION CONTROL: FY 77 (Illustration XXIII)
This table contains our planned FY 77 tasks with estimated
costs. Since they have all been covered previously, again, I
won't go into detail.
The anticipated FY 77 extramural budget is $875K. We have good
prospects for most of these projects. I have added five more priority
tasks below the line, which we also have prospects for, to indicate
potential accomplishments if an additional $650K was obtained for
FY 77. The five tasks include two important manuals of practice,
one for land management and one for storage design which will cover
pertinent cost savings areas. The helical regulator is ready for
full-scale demonstration, and like its sister, the swirl, its
cost savings implications weighed against the multi-billion dollar
estimates, are tremendous. We also have an opportunity to ride
piggy-back onto a dual use microscreening construction project
to demonstrate another important concept.
In another cost saving opportunity, we can reestablish our
full-scale test loop and make final evaluations of our developed
monitoring instruments. These instruments are foundation devices
for the program.
57
-------
RUNOFF POLLUTION CONTROL PROGRAM: FY 77
$K
SO: COMBINED SEWER POLLUTION CONTROL
DEMO NON-STRUCTURAL SOURCE CONTROL; FLUSHING OR ST. CLEANING 150
DEMO SCREENING/DAF FOR DUAL DWF/WWF TMT. OTHERS
EVAL. DAF/CONTACT STABILIZATION FOR DUAL DWF/WWF TMT. 100
SO: SEWERED & UN-SEWERED POLLUTION CONTROL
EVAL. TMT-PARK CONCEPT FOR CITY-WIDE APPROACH TO CSO CONTROL 100
CSO REC. WATER IMPACT ANALYSIS/POLLUTANT LOADINGS 400
SO: HYDRAULIC MODIFICATION
EVAL. SED./EROS. CONTROL TECHNIQUES, NORTHERN PLAINS 75
USERS MANUAL - POL. CONTROL FROM CONSTRUCTION ACTIVITIES 50
TOTAL ANTICIPATED BUDGET 875
SO: COMBINED SEWER POLLUTION CONTROL
DEMO HELICAL FLOW REG./SOL IDS-LIQUID SEPARATOR
STORAGE DESIGN MANUAL
EVAL. SCS DEVELOPED INSTRUMENTATION
DEMO DUAL USE FULL-SCALE MICROSCREENING
SO: SEWERED & UN-SEWERED POLLUTION CONTROL
MANUAL OF PRACTICE FOR LAND MANAGEMENT
ADDITIONAL REQUIRED
200
50
100
100
200
650
58
XXIII
-------
CAPITAL COSTS COMPARISONS FOR SCS CONTROL/TREATMENT (Illustration XXIV)
In this illustration we are trying to show a capital cost compari-
son for various SCS control and treatment methods.
As you can see, sewer separation is very costly with a
national average of $20,000/acre. In-system control storage costs
were found to be as low as $0.02 and $0.25/gal for Detroit and
Seattle, respectively. These figures represented 1/1Oth the
cost for large off-line facilities, and l/25th the costs for separa-
tion in Detroit and Seattle, respectively. Off-line storage varies
from $0.03 to $4.75/gal depending on whether earthen or concrete
basins are employed.
Per acre costs can only be given in wide ranges since they
significantly vary with climate, receiving water, terrain, degree
of urbanization, sewer network configuration, etc. Per capita
and per acre unit costs may be applicable for gross estimating;
but it is best to fix unit costs per gallon for storage, and per
mgd for treatment, as design factors for the user engineer
confronted with site-specific conditions.
These data are based on a limited number of specific
projects; thus they represent only a range of placement. In extra-
polating these costs into master plan systems for cities, the
totals frequently approach $500 - $1,000 per capita.
59
-------
TYPICAL CAPITAL COSTS FOR SCS CONTROL/TREATMENT
(ENR 2000)
COMPONENT DEVICES
SEPARATION
STORAGE
IN-LINE
OFF-LINE
-EARTHEN
-CONCRETE TANKS
TREATMENT
PHYSICAL W&W/O CHEMICALS
-FINE SCREENING/MICROSTRAINING
-SEDIMENTATION
-HI-RATE FILT
-DISS AIR FLOAT
-SWIRL
BIOLOGICAL
-CON. STAB/TRICK. FILTER
-LAGOONS
PHYSICAL-CHEMICAL SYSTEMS
DISINFECTION
-CONVENTIONAL
-HI-RATE(STATIC MIXING)
INTEGRATED SYSTEMS
STORAGE/TRMT/ REUSE
-TREATMT-PARK CONCEPT
LAND MANAGEMENT
STRUCTURAL
-DIVERSION BERMS
NON-STRUCTURAL
-STREET CLEANING
$/GAL
0.02 - 0.25
(DETROIT) (SEATTLE)
0.03-0.26
1.00-4.75
$/MGD
5,000/12,000
10,000-50,000
70,000
40,000
6,000 (SYRACUSE)
2,000 (LANCASTER)
80,000
17,000
150,000-2xlQ6
1,500
900
IXIO'IKINGMAN LAKE)
17,000(MT. CLEMENS)
$/ACRE
10,000 (SEATTLE)
6,500 (DES MOINES)
32,000 (CLEVELAND)
20,000-NATIONAL AVE.
400 (SEATTLE)
250 (MINNEAPOLIS)
7,000 (JAMAICA, NYC)
2,000/13,000
3,500-6,500
10,000
6,500 (MILWAUKEE)
SOO(SYRACUSE)
SOO(LANCASTER)
1,700
5,000
10,000(KINGMAN LAKE)
5,000(MT. CLEMENS)
160
7
60
XXIV
-------
Physical treatment costs range between $2,000 to $35,000/mgd;
whereas physical with chemical treatment varies between $35,000
and $80,000/mgd. Biological treatment ranges between $17,000 and
$80,000/mgd depending on whether land is available for lagooning
or if we resort to contact stabilization or trickling filtration.
As can be seen from the table, costs for the swirl at $2,000/mgd and
$500/acre are considerably lower than other forms of treatment installation,
Bringing your attention to land management, it is seen from pre-
liminary figures that we can potentially derive cost-effectiveness by
including these techniques.
It must be mentioned that the various alternatives offer different
degrees of removal which will have a significant bearing on the
selection process.
SEATTLE: IN-LINE STORAGE IS COST-EFFECTIVE (Illustration XXV)
A case study illustrating cost-effectiveness by Seattle's
flow routing approach follows:
Costs
The Seattle in-line storage system covering 13,250 acres costs
$5.3M which is equivalent to $400 per acre as opposed to tens of
thousands of dollars per acre for other alternatives. A specific
61
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XXV
-------
Seattle study revealed $10,000 per acre for separation. The low
cost is attributed to a quasi-structural system which takes advan-
tage of the existing combined sewer network; and control gates
installed at strategic points only. The system is highly signal
and computer oriented with minimal hardware requirements. In fact,
one-half the costs were for computers and related software. Of
course, in-line storage is site specific since implementation of
the concept requires a relatively large and flat existing combined
system.
Pollutant Reduction
Overflow and pollutant reduction from 12 major overflow
points averaged 55 and 68 percent, respectively. Also, 90 per-
cent of the overflow volume was reduced by experimental automatic
control.
Effectiveness
Effectiveness of the system is proven by a one to two mg/1
D.O. increase and a 50% coliform reduction in the receiving
water.
DES MOINES: CONTROL COSTS VS. D.O. VIOLATIONS (Illustration XXVI)
Based on a study for the City of Des Moines using a simplified
63
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XXVI
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receiving water model, four control alternatives were compared con-
sidering cost and true effectiveness in terms of frequency of D.O.
standard violations.
As the illustration depicts, 25 percent BOD removal of WWF
coupled with secondary treatment of DWF results in slightly higher
D.O. levels in the receiving water than tertiary treatment and no
control of urban runoff. The annual cost of 25 percent BOD
removal for WWF is 25 percent of the cost for tertiary treatment.
However, existing DWF treatment facilities exhibit a comparable
effect to these two options at no additional cost. A significant
increase in the minimum D.O. levels of the Des Moines River is
obtained by 75 percent BOD removal of WWF. However, the annual
cost of this level of control is significantly higher than the
cost of tertiary treatment. The application to Des Moines demonstrated
clearly, the overwhelming effect of urban runoff pollution on
critical D.O. concentrations. The cost-effectiveness of various
treatment alternatives can be determined realistically only by a
continuous analysis of the frequency of water quality violations.
In the selection of the "best" control strategy, other factors
may become important, such as: (1) recovery of receiving waters
from shock loads during runoff periods, (2) local and regional
water quality goals, and (3) public willingness to pay the costs
associated with each level of control.
65
-------
CONCLUSION
The pertinent research needs in the areas of solution method-
ology, non-structural and structural control and treatment tech-
niques, and integrated systems have been covered in enough detail
so we must conclude with an item of overlying importance. Man-
dates of the law are upon us, emphasizing WWF pollution control;
monies are being spent at large scale by EPA and others for water
pollution cleanup. In order for governments to execute their
function in this area properly, it is a must that WWF pollution
be considered.
66
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TECHMICAL REPCi'T DATA
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