HomeMy Public PortalAboutFee Fee Creek TMDL ARAP_FINAL_April_2023 FEE FEE CREEK
E. coli TMDL ASSUMPTIONS AND
REQUIREMENT ATTAINMENT PLAN
April 2023
Prepared by Metropolitan St. Louis Sewer District in coordination with its MS4 co-permittees.
MSD & MS4 Co-permittees
Fee Fee Creek E. coli TMDL ARAP
TABLE OF CONTENTS
1.0 Introduction and Purpose.......................................................................................................................... 3
1.1 Fee Fee Creek E. coli TMDL ............................................................................................................... 3
1.2 MS4 Permit Requirements ................................................................................................................... 6
2.0 E. coli Bacteria and its Potential Sources ................................................................................................. 6
2.1 Public Sanitary Sewer Infrastructure .................................................................................................... 7
2.2 Individual Sewage Disposal Systems ................................................................................................... 9
2.3 Urban Stormwater Runoff .................................................................................................................... 9
2.4 Riparian Conditions ........................................................................................................................... 10
2.5 Illicit Straight Pipe Discharges ........................................................................................................... 10
3.0 TMDL Implementation Activities .......................................................................................................... 11
3.1 St. Louis County Phase II Stormwater Management Plan ................................................................. 11
3.1.1 MCM #1, Public Education and Outreach on Stormwater Impacts ............................................... 12
3.1.2 MCM #2, Public Involvement/Participation in Program Development ......................................... 13
3.1.3 MCM #3, Illicit Discharge Detection and Elimination .................................................................. 13
3.1.4 MCM #4, Construction Site Stormwater Runoff Control .............................................................. 15
3.1.5 MCM #5, Post-Construction Stormwater Management in
New Development and Redevelopment ......................................................................................... 15
3.1.6 MCM #6, Pollution Prevention/Good Housekeeping for Municipal Operations ........................... 17
3.2 Project Clear ....................................................................................................................................... 18
3.2.1 Sanitary Sewer Overflow Control Master Plan .............................................................................. 18
3.2.1.1 Sewer System Evaluation Survey (SSES) ....................................................................... 18
3.2.1.2 Master Plan Projects ........................................................................................................ 18
3.2.2 Capacity, Management, Operations, and Maintenance Program ................................................... 20
3.2.3 Fats, Oil, and Grease Program ........................................................................................................ 21
3.3 TMDL Best Management Practices Targeting Bacteria .................................................................... 22
4.0 Evaluation............................................................................................................................................... 24
LIST OF TABLES
Table 1. TMDL requirements for E. coli bacteria at specific flows in Fee Fee Creek (WBID 1704). ................. 5
Table 2. Summary of sanitary sewer gravity pipes by pipe diameter and material in the Fee Fee Creek
watershed as of November 11, 2022. .................................................................................................................... 7
Table 3. Summary of sanitary sewer pipes by pipe diameter and material that have received rehabilitation in
the Fee Fee Creek watershed as of November 11, 2022. ...................................................................................... 8
Table 4. Summary of capacity and non-capacity overflows and bypasses for Fee Fee Creek watershed,
10/01/2019 - 09/30/2022. ...................................................................................................................................... 9
Table 5. Repaired and identified defective laterals in the Fee Fee Creek watershed, 2016-2022. ...................... 11
Table 6. TMDL Best Management Practices targeting bacteria in the Fee Fee Creek watershed. ..................... 23
LIST OF FIGURES
Figure 1. Impaired reaches of Fee Fee Creek as described in the Fee Fee Creek E. coli TMDL, and watershed
location in St. Louis County, Missouri. ................................................................................................................ 4
APPENDICES
Appendix A. SSO Control Master Plan Projects in Fee Fee Creek Watershed
Appendix B. Bacteria and Nutrient Best Management Practices Strategy Review
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Fee Fee Creek E. coli TMDL ARAP
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1.0 Introduction and Purpose
Fee Fee Creek first appeared on Missouri’s Section 303d list of impaired waters for elevated
concentrations of Escherichia coli (E. coli) bacteria in 2012. For Fee Fee Creek, in-stream concentrations
of E. coli have been found to exceed Missouri’s water quality criterion for its designated use of Whole-
Body Contact Recreation Category B, which is set at 206 E. coli counts per 100 milliliters of water (206
counts/100mL). According to Missouri’s 303d listing methodology, a water designated for Whole Body
Contact Recreation, Category B, is determined to be impaired by bacteria if the geometric mean in a
given recreational season exceeds the water quality criterion (206 counts/100mL) in any of the last three
years with available data. At least five samples are needed from a single recreational season, which is
defined as the period from April 1 through October 31. Fee Fee Creek remained on Missouri’s Section
303d list of impaired waters for E. coli from 2012 to 2020. On October 14, 2020, the United States
Environmental Protection Agency (USEPA) approved Missouri’s Total Maximum Daily Load (TMDL)
for Fee Fee Creek (new) St. Louis County for Pathogens as indicated by E. coli1.
As required by the Federal Clean Water Pollution Control Act, the Missouri Department of Natural
Resources (MDNR) issues the Metropolitan St. Louis Sewer District (MSD), St. Louis County, and 59 St.
Louis County municipalities a general operating permit to discharge authorized stormwater from the
Municipal Separate Storm Sewer System (MS4) servicing the Plan Area to waters of the state. The most
recent permit (General Operating Permit MOR040005) was issued on November 1, 2021 and it requires
regulated MS4s identified in a TMDL with an applicable Wasteload Allocation (WLA) to implement
steps toward the attainment of the applicable WLA in accordance with 40 CFR 122.44(k)(2) and (3). In
this case, MSD and its co-permittees are required to develop an Assumptions and Requirement
Attainment Plan (ARAP) to address applicable assumptions and requirements in the Fee Fee Creek
Watershed TMDL for Pathogens as indicated by E. coli (referred to herein as Fee Fee Creek E. coli
TMDL).
The purpose of this document is to fulfill requirements in the MS4 permit issued to MSD and its co-
permittees, specifically Section 6.1. MS4s Subject to Total Maximum Daily Loads (TMDL). This TMDL
ARAP will address the aggregated wasteload allocations assigned to the MS4 area in the Fee Fee Creek
E. coli TMDL. Procedures and activities to be implemented in accordance with the MS4 permit are
provided herein. Most importantly, this TMDL ARAP includes a description of implementation activities
and best management practices (BMPs) that will be used to target known sources of E. coli bacteria
specific to the Fee Fee Creek watershed, as well as a prioritized schedule for their implementation. BMP
effectiveness will be evaluated after implementation, and those found to be ineffective will be revised or
replaced accordingly. Both the Fee Fee Creek E. coli TMDL and TMDL Strategies 2 documents were used
in the development of this TMDL ARAP.
1.1 Fee Fee Creek E. coli TMDL
Fee Fee Creek is an urban stream located within St. Louis County and flows into Creve Coeur Creek,
approximately 0.9 miles upstream from where Creve Coeur Creek empties into the Missouri River. The
Fee Fee Creek watershed drains approximately 18.6 mi2 (48.2 km2) and encompasses a large portion of
the City of Maryland Heights. The lower 17 percent (8.15 km2) of the watershed resides in the Missouri
River 500-year floodplain, which is less developed. The largest agricultural area in the watershed is
within the Missouri River floodplain, in the Howard Bend Levee District. It is because of the agricultural
1 Missouri Department of Natural Resources Water Protection Program. 2020. Total maximum daily load
(TMDL) for Fee Fee Creek (new), St. Louis County. Pollutants of concern: Pathogens. Submitted:
September 14, 2020. Approved: October 14, 2020. 37pp.
2 Missouri Department of Natural Resources Water Protection Program. 2020. Total maximum daily load
implementation strategies for Fee Fee Creek, St. Louis County. Pollutants of concern: Pathogens. 23pp.
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use that the floodplain is on average less developed. In total, Fee Fee Creek is approximately 7.7 miles
long.
The Missouri Use Designation Dataset identifies a 1.5-mile (2.4 kilometer) length of Fee Fee Creek as
water body identification number (WBID) 1704. The reach identified as WBID 1704 is listed as Class P
water and has been assigned the following designated uses: Livestock and Wildlife Protection; Irrigation;
Warm Water Habitat; Human Health Protection; Secondary Contact Recreation; and Whole-Body
Contact Recreation Category B. As described in the Fee Fee Creek E. coli TMDL, the stream reach
impaired by bacteria is shown in Figure 1. The segment extends from the confluence with Creve Coeur
Creek to approximately 0.1 miles (0.16 km) east of Vigus Road. Beginning approximately 1 mile (1.6
km) upstream of WBID 1704, Fee Fee Creek is designated a Metropolitan No-Discharge stream. For
Metropolitan No-Discharge streams, no water contaminant except uncontaminated cooling water,
permitted stormwater discharges, and excess wet-weather bypass discharges that do not interfere with
beneficial uses, may be discharged in the watershed. The Fee Fee Creek watershed includes portions of
the following St. Louis County MS4 co-permittees: St. Louis County (unincorporated areas); City of
Bridgeton; City of Creve Coeur; City of Maryland Heights; City of Overland; and City of St. Ann. The
watershed also contains one municipality that is not a co-permittee, the Village of Champ. The Missouri
Department of Transportation has a TS4 permit and operates according to their Stormwater Management
Plan within the watershed.
Figure 1. Impaired reaches of Fee Fee Creek as described in the Fee Fee Creek E. coli TMDL, and
watershed location in St. Louis County, Missouri.
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A TMDL is a calculation that sets the amount of pollutant a water body can assimilate without exceeding
the water quality criterion for that particular pollutant. The TMDL allocates the pollutant load among
three components:
1) Wasteload allocation (WLA) for all point sources and MS4 Operators;
2) Load allocation (LA) for all nonpoint sources and natural background sources; and,
3) Margin of Safety (MOS) to account for any uncertainty in data or model assumptions.
The TMDL is equal to the sum of the wasteload allocation, load allocation, and margin of safety as
expressed in the following equation:
TMDL = ΣWLA + ΣLA + MOS
The Fee Fee Creek E. coli TMDL was developed using the numeric target concentration of 206
counts/100mL, and a load duration curve for each waterbody. This numeric concentration represents
Missouri’s water quality criteria for Whole Body Recreation Category B. The load duration curve for Fee
Fee Creek applied average daily flow data from January 1, 2004 to June 18, 2019 from the USGS gaging
station 06935955 on Fee Fee Creek near Bridgeton, MO. Flow data from this gage were adjusted based
on the ratio of the impaired stream’s drainage area to the gage’s drainage area. The numeric target
concentration was multiplied by the corrected average daily flow and a conversion factor to calculate the
daily load (counts/day) at specific discharges.
Regulation of stormwater discharges from systems owned or operated by MS4s in Fee Fee Creek
watershed is covered under two MS4 permits. The first MS4 permit is held by MSD and its 60 co-
permittees (referred to as MSD MS4 permit from hereon) and covers a jurisdiction of approximately 95.9
percent of the Fee Fee Creek watershed that is part of a MS4. The second is a site specific MS4 permit
held by the Missouri Department of Transportation (Permit No. MO-0137910) and covers the remaining
4.1 percent. There are no other permitted facilities in Fee Fee Creek watershed that might reasonably
contribute to bacteria loading, thus all of the WLA was assigned to the MS4 area. Furthermore, since it
was not possible to accurately disaggregate E. coli loading for each MS4, the WLA was assigned as an
aggregate wasteload to the total MS4 area. Please see Table 1, adapted from the Fee Fee Creek E. coli
TMDL1.
Table 1. TMDL requirements for E. coli bacteria at specific flows in Fee Fee Creek (WBID 1704).
Percentile Flow
Exceedance
Flow
(cfs)
TMDL
(counts/day)
MS4 WLA
(counts/day)
LA
(counts/day)
95 1.05 5.29E+09 4.76E+09 5.29E+08
75 2.78 1.40E+10 1.26E+10 1.40E+09
50 5.61 2.83E+10 2.55E+10 2.83E+09
25 13.90 7.00E+10 6.30E+10 7.00E+09
10 128.42 6.47E+11 5.82E+11 6.47E+10
cfs =cubic feet per second; WLA = wasteload allocation; LA = load allocation
Both on-site wastewater treatment systems and minor amounts of agricultural and urban runoff were
identified as potential nonpoint sources in the Fee Fee Creek E. coli TMDL. On-site wastewater treatment
systems, if functioning properly, should not be contributing to the impaired condition of Fee Fee Creek,
and are assigned a load allocation of zero. Other nonpoint sources potentially contribute bacteria loads
through surface runoff and are assigned load allocations that vary with flow as can be seen in Table 1.
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The margin of safety component is considered implicit because of conservative assumptions used in the
TMDL model, the use of multiple years of stream discharge data collected under a complete range of
conditions, reduced uncertainty of the sources of the bacteria impairment and remediation of bacteria
sources through MSD’s Project Clear program. In addition, the daily load estimated values used the
recreational season geometric mean while at the same time omitting bacteria decay rates, which are
overlapping conservative assumptions.
1.2 MS4 Permit Requirements
Missouri General Operating Permit MOR040005 (issued on November 1, 2021), Section 6.1.A requires
any regulated MS4 identified in an EPA approved or established TMDL with an applicable WLA shall
implement steps towards the attainment of applicable WLAs in accordance with 40 CFR 122.44(k)(2) and
(3). Section 6.1.B of the permit states the permittee shall develop a TMDL ARAP to address the TMDL’s
assumptions and requirements where applicable. The TMDL ARAP shall be incorporated into the
Stormwater Management Program (SWMP) and include, at a minimum, the following:
6.1.C (1) A plan to identify potential sources of the pollutant(s); (2) a plan to implement BMPs to
address the sources within the MS4 area; and (3) a schedule, including beginning and ending
milestones, which are expressed as month and year to implement planned BMPs. The schedule
for the implementation of the TMDL ARAP shall be completed as soon as practicable but is not
limited to the five-year term of this operating permit as attainment can take years or even multiple
permit terms.
6.1.D BMPs shall be developed or designed with a purpose of reducing the pollutant(s) of concern. The
ARAP shall list each BMP and shall contain a description of the BMP, the purpose of the BMP,
and the expected result of the BMP.
6.1.E Measurable goals shall be established for each BMP or in conjunction with multiple BMPs. (1)
Each measurable goal shall contain a statement clearly indicating how it will be established to
determine the appropriateness of identified BMPs and progress toward the expected results of the
BMP. (2) Measurable goals shall be quantifiable; however, if it is not feasible to utilize a
measurable goal that is quantifiable, then the permittee shall provide justification indicating why
the measurable goal cannot be quantifiable. (3) If applicable, measurable goals shall also utilize
interim and completion milestone dates, and a periodic frequency of measurement to document
progress. Interim and final milestone dates shall be established with a format of month and year,
or as 1st, 2nd, 3rd, 4th, and 5th year of the operating permit cycle.
6.1.F An iterative process shall be utilized by the permittee documenting how each BMP is evaluated
and subject to replacement or modification. The permittee shall apply reasonable further progress
by replacing or modifying ineffective BMPs with effective BMPs.
2.0 E. coli Bacteria and its Potential Sources
E. coli bacteria commonly inhabit the intestines of warm-blooded animals and their feces. In-stream
contributions of E. coli usually originate from humans, pets, livestock, and wildlife. There are a variety of
pathways E. coli might enter a waterway, such as stormwater runoff from agriculture and urban lands,
failing septic systems and illicit connections, and discharges from sewage infrastructure related to
wastewater treatment. The presence of E. coli measured at high concentrations indicates contamination by
fecal matter. While the broad group of E. coli bacteria are mostly considered harmless, its presence is
used an indicator of other pathogenic bacteria, viruses, and other microorganisms. Diseases from those
pathogens can cause eye, ear, nose, throat, and respiratory infections, as well as gastrointestinal illness.
Missouri’s Section 303d lists of impaired waters from 2012-2020 note the source of E. coli bacteria in
Fee Fee Creek as urban runoff/storm sewers. The Fee Fee Creek E. coli TMDL describes several specific
sources of E. coli bacteria including the sanitary sewer system, onsite wastewater treatment systems
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Fee Fee Creek E. coli TMDL ARAP
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(referred to herein as individual sewage disposal systems), urban stormwater runoff, riparian corridor
conditions, and to a lesser extent, straight pipe illicit discharges. In particular, human sources of
pathogens (e.g. sanitary sewer discharges and onsite systems) are considered a higher human health risk
depending upon the duration and type of exposure. The following information is a summary of all
potential sources of bacteria to Fee Fee Creek.
2.1 Public Sanitary Sewer Infrastructure
There are no permitted facilities that discharge domestic or municipal wastewater treatment systems in the
Fee Fee Creek watershed. Sanitary sewer infrastructure is present throughout the watershed, comprising
approximately 211 miles of pipe. A summary of public sanitary sewer pipes found in the watershed is
provided in Table 2, and a summary of sewer pipes that have received rehabilitation through cured-in-
place lining is presented in Table 3.
Table 2. Summary of sanitary sewer gravity pipes by pipe diameter and material in the Fee Fee Creek
watershed as of November 11, 2022.
VCP is vitrified clay pipe; RCP is reinforced concrete pipe; DIP is ductile iron pipe.
Pipe
Diameter
(inches)
VCP Plastic RCP Cast Iron
or DIP Sub-Total
-- Length in Feet
6" 992 1,970 -- 542 3,505
8" 408,521 536,746 -- 7,721 952,988
10" 11,109 17,871 -- 471 29,452
12" 8,818 22,181 53 1,103 32,155
15" 5,299 11,625 365 246 17,535
16" -- -- -- 177 177
18" 2,117 9,112 -- 1,901 13,130
20" -- -- -- 13 13
21" 970 10,672 -- 91 11,733
24" 3,290 16,391 1,258 1,364 22,304
30" 560 -- 7,905 -- 8,465
36" -- -- 5,804 240 6,043
42" -- 4,582 5,195 376 10,153
48" -- -- 5 102 107
54" -- -- 3,765 -- 3,765
60" -- -- 3,047 -- 3,047
72" -- -- 113 -- 113
96" -- -- 260 -- 260
Total 441,676 631,151 27,770 14,348 1,114,945
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Table 3. Summary of sanitary sewer pipes by pipe diameter and material that have received rehabilitation
in the Fee Fee Creek watershed as of November 11, 2022.
Pipe
Diameter
(inches)
VCP PVC Cast Iron DIP ABS Sub-Total
-- Length in Feet
6" 781 -- -- -- -- 781
8" 209,039 3,031 241 1,540 -- 213,851
10" 11,609 29 975 -- -- 12,613
12" 7,077 150 237 797 2,384 10,646
15" 1,591 -- -- -- 2,544 4,135
16" -- -- -- -- -- 0
18" 1,957 -- -- -- -- 1,957
20" -- -- -- -- -- 0
21" 2,288 -- -- -- -- 2,288
24" 1,250 -- -- -- -- 1,250
30" -- -- -- -- -- 0
36" -- -- -- -- -- 0
42" -- -- -- -- -- 0
48" -- -- -- -- -- 0
54" -- -- -- -- -- 0
60" -- -- -- -- -- 0
Total 235,592 3,210 1,454 2,337 4,928 247,520
VCP is vitrified clay pipe; PVC is polyvinyl chloride; DIP is ductile iron pipe; ABS is Acrylonitrile Butadiene Styrene.
In addition to sewer pipes, there are 6,106 sanitary manholes in the Fee Fee Creek watershed that fall
under public or private ownership. Manholes are mostly constructed of precast sections of concrete, cast-
in-place concrete, brick, and other materials. MSD owns and operates seven (7) sanitary pump stations
within the Fee Fee Creek watershed (Riverport 1 (P-780), Riverport 2 (P-804), Riverport 5 (P-701),
Riverport 6 (P-781), Duke Riverport (P-806), STL Ice Center (P-839), and Master Lift 1 (P-717)) in
addition to one (1) pump station, Rider Trail N (P-703), outside of the watershed which conveys sanitary
sewage through it.
All of the constructed sanitary sewer overflow (SSO) points described in the TMDL have been removed.
Constructed SSO 11623 Holly Springs (BP-078) was removed on September 27, 2019, and 11749
Westport Crossing (BP-087) was removed on September 9, 2020. The last constructed SSO in Fee Fee
Creek watershed, 1217 Crested View Drive (BP-069), was removed on November 4, 2021, as part of the
Fee Fee Creek Sanitary Relief Project.
Unintended overflows from the sanitary system however may still occur from time to time as a result of
blockages, line breaks, power failures and vandalism. A summary of dry weather capacity and non-
capacity overflows and bypasses that reached a receiving stream in the Fee Fee Creek watershed for the
period of October 10, 2019, through September 30, 2022, is provided in
Table 4.
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Table 4. Summary of capacity and non-capacity overflows and
bypasses for Fee Fee Creek watershed, 10/01/2019 - 09/30/2022.
Cause Count Remedy
Debris Blockage 4 Cleaned/Cleared
Grease Blockage 2 Cleaned/Cleared
Broken Pipe 2 Repaired
Total 8 --
As part of the SSO Master Plan requirement in MSD’s federal consent decree 3, MSD conducted a Sewer
System Evaluation Survey (SSES) for the Fee Fee Creek watershed. SSES findings related to sewer
defects are described in Section 3.2.1.1 of this ARAP, and SSO Master Plan remedial projects are
described in Section 3.2.1.2 and Appendix A.
2.2 Individual Sewage Disposal Systems
Individual sewage disposal systems are considered nonpoint sources of pollution. Failing systems are
known sources of bacteria that can enter nearby streams through surface and subsurface flows. As
referenced in the E. coli TMDL, a study conducted by the Electric Power Research Institute (EPRI)
suggests that up to 50 percent of these systems in Missouri may be failing 4.
In a survey conducted specifically for MSD to gather information on environmental awareness in MSD’s
service area, out of 570 residents contacted by either mail or online, 4% (22) indicated they had a septic
system at their home 5. When residents were asked if their septic system had been serviced in the last five
years, 64% (14) of those indicated it had, 14% (3) said it had not, and 23% (5) were unsure. Of 18
residents asked about the age of their system, 28% (5) said their septic system was more than 30 years
old.
The prevalence of individual sewage disposal systems in the Fee Fee Creek watershed has been reduced
over time. According to MSD Rules and Regulations, treatment using a septic system is not allowed when
public sanitary sewers are within 200 feet of any point on a property and determined to be available, or
when a lot is less than three (3) acres in size. Still, there are approximately 368 parcels in the Fee Fee
Creek watershed combined which are suspected of not having a connection to the public sewer1. Non-
sewered parcels include those with structures and those without, though it is not directly known how
many parcels with existing structures have an individual sewage disposal system in operation. Therefore,
contributions of bacteria from failing individual sewage disposal systems are likely, however the scope of
the problem within Fee Fee Creek watershed is not entirely known.
2.3 Urban Stormwater Runoff
Urban stormwater runoff is known to contain high levels of bacteria and is another potential contributor
of E. coli to Fee Fee Creek. According to a study conducted by USGS 6 median E. coli densities from six
3 United States of America and the State of Missouri, and the Missouri Coalition for the Environment Foundation v.
Metropolitan St. Louis Sewer District, No. 4:07-CV-1120.
4 Electric Power Research Institute. 2000. Advanced On-Site Wastewater Treatment and Management Market
Study: Volume 2: State Reports. TR-114870. 224pp.
5 ETC Institute for Metropolitan St. Louis Sewer District. 2017. Metropolitan St. Louis Sewer District
environmental awareness survey. ETC Institute. 47pp.
6 Wilkison, D.H., Davis, J.V. 2010. Occurrence and sources of Eschericia coli in metropolitan St. Louis
streams, October 2004 through September 2007: U.S. Geological Survey Scientific Investigations Report
2010-5150. 57pp.
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stream locations in MSD’s service area were strongly correlated with the percentage of upstream
impervious cover. Runoff from both pervious and impervious areas has the potential to pick up and
transport bacteria from domestic and wild animal waste. Pet waste may enter local waterways from
residential areas, as well as areas open to the public, such as dog parks, parks, trails, or other recreational
areas utilized by pet owners. Wild animals like raccoons inhabiting the storm system or nuisance geese
residing on local ponds are also potential sources. Additionally, bird droppings on roadways can easily be
carried into the storm system and transported to streams during rain events. Waste from livestock, poultry,
pets, and wildlife are all known to contribute to E. coli concentrations in urban streams. On average, 10
percent of E. coli in six metropolitan St. Louis streams was traced to dogs and another 20 percent to
geese6. Note, this USGS study included data from adjacent drainages, but not the Fee Fee creek
watershed.
Urban runoff discharges from the two MS4 permitted systems are considered potential point sources of E.
coli to Fee Fee Creek. As previously discussed, the catchments that contribute stormwater runoff to the
outfalls permitted under the MSD MS4 permit were not identified during development of the TMDL.
Stormwater runoff from areas not served by the MS4s is considered a nonpoint source. Urban areas
outside of the defined MS4s exist in Fee Fee Creek watershed, thus a stormwater driven nonpoint source
pollution LA was assigned in the Fee Fee Creek E. coli TMDL, which was calculated as the remainder of
the available loading capacity after the WLA was calculated.
2.4 Riparian Conditions
Riparian corridor conditions in the watershed were listed in the Fee Fee Creek E. coli TMDL as a likely
source of bacteria. The riparian corridor is defined as including a 30-meter area on each side of all
streams in the watershed that are included in the 1:24,000-scale National Hydrography Dataset. As is the
case with the watershed as a whole, the dominant land cover types in the riparian corridor are those
associated with varying degrees of development and imperviousness. More than 51 percent of the riparian
corridor in the Fee Fee Creek watershed is categorized as having low to high intensity development and
greater than 20 percent impervious coverage. Open space development, which contains less than 20
percent impervious cover, makes up approximately 25 percent of the riparian corridor. In total, developed
land cover types account for almost 76 percent of the total coverage in the riparian corridor. Runoff from
these areas that has come in contact with pet or wildlife wastes can contribute bacteria loads to the MS4
or directly to an adjacent water body. For this reason, the riparian corridor condition within the watershed
is a potential contributing source of bacteria to Fee Fee Creek, and those contributions are included in the
total MS4 WLA.
2.5 Illicit Straight Pipe Discharges
Illicit straight pipe discharges occur where household waste is discharged directly to a stream or area of
land and are different from illicitly connected sewers. Due to the presence of a sewerage system
throughout Fee Fee Creek watershed, illicit straight pipe discharges are not expected to be significant
contributors of E. coli. There is, however, potential for privately owned sewer laterals to fail on occasion
and discharge untreated sewage to waterways. Illicit discharges such as these have been found across
MSD’s service area through Illicit Discharge Detection and Elimination work performed under Minimum
Control Measure #3 of MSD’s MS4 permit. Failed sewer laterals are repaired by the homeowner, usually
with partial funding assistance from a local lateral repair program.
MSD and its MS4 co-permittees developed and maintain a database of properties that have participated in
a sewer lateral repair program and/or were notified of a defective lateral, again under Minimum Control
Measure #3. Reported data from this monitoring effort is summarized in Table 5 below. In the Fee Fee
Creek watershed, there were 595 properties that conducted a lateral repair and/or were notified of a
defective sewer lateral between 2016 and 2022.
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Table 5. Repaired and identified defective laterals in the Fee Fee
Creek watershed, 2016-2022.
Municipality Repaired and Defective
Sewer Laterals
Bridgeton 1
Creve Coeur 3
Maryland Heights 349
Overland 1
St. Ann 8
Unincorporated St. Louis County 233
Total 595
3.0 TMDL Implementation Activities
The implementation of activities provided in this ARAP will aim to reduce bacteria loading in Fee Fee
Creek. In large part, those activities will be implemented through ongoing programs already being
executed. The two main implementing programs are the St. Louis County Phase II Stormwater
Management Plan (Fourth Term Permit 2021-2026) and MSD’s consent decree obligations, established as
part of the United States of America and the State of Missouri, and the Missouri Coalition for the
Environment Foundation v. Metropolitan St. Louis Sewer District, No. 4:07-CV-1120. Additional
activities beyond these two programs will harness information generated through existing MSD
maintenance operations with the goal of developing and implementing further bacterial reduction.
3.1 St. Louis County Phase II Stormwater Management Plan
The St. Louis County Phase II Stormwater Management Plan (Fourth Term Permit 2021-2026), referred
to herein as the Stormwater Management Plan (SWMP), was developed in compliance with the MS4
permit issued to MSD and its co-permittees. The permit requires MS4s, MSD and its co-permittees, to
implement activities via an iterative process to reduce the discharge of pollutants to the maximum extent
practicable (MEP) into the MS4 for the goal of attainment with Missouri’s Water Quality Standards. The
SWMP, which was approved by MDNR on August 26, 2021, contains six minimum control measures
(MCM) that include measurable activities for addressing requirements under Part 4 of the MS4 permit.
Goals for each activity are set in each year of the permit, and annual reports are submitted to MDNR
regarding the status of each goal. Goals are reviewed annually and the SWMP may be updated as needed
or following renewal of the MS4 permit.
Continued implementation of the SWMP through the iterative evaluation process will result in a
significant reduction of pollutants discharged to waters in the plan area, including the discharge of E. coli
bacteria to Fee Fee Creek. The result of implementing each activity will be reported through the SWMP
annual reporting process.
The following is a summary of SWMP activities expected to reduce bacteria contributions to Fee Fee
Creek. Each activity references its corresponding goal in the SWMP. Prioritization activities, measurable
goals and milestones, implementation schedules, and the iterative evaluation process for the activities
described below will be consistent with those already identified in the SWMP. The strategy for evaluating
the effectiveness of the SWMP is based upon assessing three key performance characteristics including
(1) Program Operations and Activities, (2) Social Indicators and (3) Water Quality Data Analysis across
each of the MCM activities. Please review the SWMP for a complete description of all activities under
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each MCM along with their schedule for implementation7. All activities in the SWMP shall be reviewed
and evaluated for effectiveness annually to determine if they should be replaced or modified.
3.1.1 MCM #1, Public Education and Outreach on Stormwater Impacts
MSD and its co-permittees are required to implement a public education program to distribute educational
material to the community and/or conduct equivalent outreach activities about the impacts of stormwater
discharges on waterbodies and the steps the public can take to reduce pollutants in stormwater runoff.
This program targets several pollutant sources that directly or indirectly address bacteria, including pet
waste; yard management; individual sewage disposal systems; land disturbance; and fats, oils, and grease
(FOG). Under MCM#1, the current SWMP lists 23 individual activities that are intended to identify
entities that may have an impact on stormwater, identify target audiences to foster nonpoint source
pollution and water quality awareness, and ultimately increase awareness and positive behavior changes
for those in the community. Of those 23 activities, 17 pertain to bacterial reduction and are noted as
follows:
1. Query MSD’s Asset Management System for list of active food service and restaurant
establishment facilities (Goal 3 of SWMP). Active food service and restaurant facilities are
among the target audience for distributing educational materials containing information on
bacteria pollution and prevention.
2. Collect a stormwater education survey (Goal 6 of SWMP). The survey will allow MSD to
monitor trends in public water quality awareness in its service area and will yield valuable
information about awareness for bacteria pollution.
3. Maintain a database of all K-12 public and private school districts in the plan area (Goal 7 of
SWMP). The database will be used to foster nonpoint source pollution and water quality
awareness in the community by identifying those schools which provide stormwater education.
Bacteria pollution prevention is a component of stormwater education.
4. Develop and distribute stormwater messages for MSD bills and websites (Goal 8 of SWMP).
Pet waste and individual sewage disposal systems are among the messaging topics.
5. Maintain and provide a library of stormwater education materials for the purpose of providing
brochures, flyers, and other media that can be used at public events and upon request (Goal 9 of
SWMP). Educational materials will include information on bacteria pollution and prevention.
6. Provide presentations and educational materials to families and homeowners for the purpose of
fostering nonpoint source pollution and water quality awareness in the community (Goal 10 of
SWMP). Presentations and educational materials will include information on bacteria pollution
and prevention.
7. Post pet waste signs in parks for the purpose of fostering nonpoint source pollution and water
quality awareness in the community (Goal 11 of SWMP). The effort will directly address pet
waste as a source of bacteria.
8. Maintain a database of community partners with water pollution education interests that can
work with MSD to foster nonpoint source pollution and water quality awareness for target
pollutants, including bacteria (Goal 12 of SWMP).
9. Provide educational materials to industrial entities, waste haulers, and food service and
restaurant establishments to foster nonpoint source pollution and water quality awareness in the
community (Goal 13 of SWMP). Presentations and education materials will include
information on bacteria pollution and prevention.
10. Provide presentations and educational materials to trade associations, schools, and watershed
groups to foster nonpoint source pollution and water quality awareness (Goal 14 of SWMP).
Presentations and education materials will include information on bacteria pollution and
prevention.
7 The SWMP is available on MSD’s website, https://msdprojectclear.org/.
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11. Partner with community organizations to provide stormwater information to a broad audience
to foster nonpoint source pollution and water quality awareness (Goal 15 of SWMP).
Stormwater information covers bacteria pollution and prevention among the target pollutants.
12. Advertise videos to be utilized in social media platforms in order to provide education to broad
audiences (Goal 16 of SWMP). Messaging to include information on bacteria pollution and
prevention.
13. Provide training to educators, watershed group members, and others on how to use the
Enviroscape® watershed models for the purpose of engaging citizen volunteers on how to
educate students on sources of pollution and best practices, providing additional resources
(Goal 19 of SWMP). Education and training will cover bacteria pollution and prevention.
14. Provide Enviroscape® watershed models for community use for the purpose of fostering
nonpoint source pollution and water quality awareness (Goal 20 of SWMP). Education will
cover bacteria pollution and prevention.
15. Provide storm drain marker instructions and equipment to citizen volunteers for the purpose of
fostering nonpoint source pollution and water quality awareness (Goal 21 of SWMP). Storm
drain marking will address bacteria among other target pollutants.
16. Develop a storm drain marking GIS map to facilitate community opportunities to participate in
the storm drain marking program (Goal 22 of SWMP). Storm drain marking will address
bacteria among other target pollutants.
17. Provide resources, as available, to residential, institutional, and commercial landowners and
citizen volunteer organizations that promote green infrastructure and other healthy water
programming (Goal 23 of SWMP). Resources will foster nonpoint source pollution and water
quality awareness, and target stormwater pollutants including bacteria.
In addition to these efforts that are conducted within the framework of the MS4 SWMP and co-permittee
relationship, public and non-profit organizations, funded by the EPA through the Clean Water Act, may
also be implementing non-point source water quality improvement strategies and education that are
synergetic to the MS4 SWMP and this TMDL ARAP.
3.1.2 MCM #2, Public Involvement/Participation in Program Development
Under MCM #2, MSD and its co-permittees implement a public involvement/participation program that
provides opportunities for the public in development and oversight of the SWMP, as well as opportunities
for involvement with the permittee’s renewal application. Collectively, there are six SWMP activities that
address MCM#2 requirements. Three of these activities have specific goals under MCM#2, whereas the
remaining three activities which are necessary to meet MS4 permit requirement 4.2.C (i.e., Goals 8, 31
and 46 of SWMP) are actually included under different MCMs and are described in their respective
sections of this report. Goals 8, 31 and 46 of the SWMP aim to reduce bacteria concentrations in
stormwater runoff and improve water quality.
3.1.3 MCM #3, Illicit Discharge Detection and Elimination
As part of MCM #3, MSD carries out an Illicit Discharge Detection and Elimination (IDDE) Program. An
illicit discharge is any discharge to the stormwater system that is not composed entirely of stormwater,
and may result from illegal dumping, a direct connection from the sanitary sewer to the storm sewer, or an
indirect connection from improper surface discharges to the storm sewer. Under this program, MSD
surveys channels in priority areas likely to have illicit discharges within the plan area at least once every
five years, inspects outfalls for illicit discharges, responds to reports of illegal dumping, and conducts
timely elimination of prohibited discharges. Priority areas for channel surveys are based on the history of
IDDE activities in the watershed, strategic databases (e.g., properties known or likely to utilize a septic
system), water quality impairments, established TMDLs, and approved TMDL ARAPs. In the past, staff
conducting illicit discharge surveys have discovered and eliminated illegal dumping of pet waste, leaking
sewer lines, and failing private sewer laterals and onsite septic systems. MSD’s implementation of the
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IDDE program is expected to be one of the most impactful actions to improve water quality in Fee Fee
Creek watershed.
There are 15 activities implemented under MCM #3, all of which either target sources of bacteria directly
or facilitate the process of identifying and eliminating bacteria sources. Those activities are as follows:
1. Maintain a Geographic Information System (GIS) showing constructed MS4 outfalls and
receiving streams (Goal 27 of SWMP). This GIS is used to locate and view outfalls in the plan
area, and in the process identify and investigate sources of bacteria.
2. Use map update work orders to track any modifications to the sewer map for the purpose of
maintaining current information on the storm sewer system in the plan area watersheds (Goal
28 of SWMP). This activity will improve the identification, tracking, and elimination of
potential sources of bacteria.
3. Enforce MSD ordinance No. 15048, and others as required (Goal 29 of SWMP). Ordinance No.
15048 serves as MSD’s legal enforcement tool for eliminating prohibited discharges, including
those that may be a source of bacteria.
4. Survey Plan Area natural channels in 2020 303(d) impaired stream listing watersheds
(Excluding the Missouri River major watershed) identified on MSD’s basemap once every five
years (Goal 30 of SWMP). This activity will lead to detecting and eliminating illicit discharges,
including those that are a source of bacteria.
5. Respond to reports of illegal dumping, which will include detecting and eliminating sources of
bacteria (Goal 31 of SWMP).
6. Maintain operating procedures for tracing illicit discharges from the public sewer system (Goal
32 of SWMP). The purpose is to provide for timely and efficient illicit source identification,
including sources of bacteria.
7. Maintain operating procedures for eliminating illicit discharges (Goal 33 of SWMP). The
purpose is to provide for timely and efficient illicit source elimination, including sources of
bacteria.
8. Provide public outreach communications tools (e.g. brochures, etc.) to sources of non-
stormwater discharge that could be substantial contributors of pollutants into the MS4, such as
street cleaning, residential car washing, and residential swimming pools (Goal 34 of SWMP).
The purpose is to foster stormwater nonpoint source pollution awareness and behavior change
in the community and some of the communication tools will include information about bacteria.
9. Maintain and distribute brochures, door hangers, and other communication tools that inform
about hazards associated with illegal discharges and improper disposal of waste (Goal 35 of
SWMP). This activity will foster stormwater nonpoint source pollution awareness and behavior
change in the community and some of the materials will include information on bacteria.
10. Maintain operating procedures for field testing and surveying to help identify chemicals
indicative of illicit discharges for the purpose of timely and efficient illicit source identification
and elimination, including those that are a source of bacteria (Goal 36 of SWMP).
11. Maintain and annually review findings from channel surveys and inspect previous findings
(Goal 37 of SWMP). The purpose of this activity is to identify priority areas for potential
monitoring and follow-up, including those that may be sources of bacteria.
12. Review representative water quality data collected by MSD to prioritize investigation areas and
identify potential source areas, including those that may be contributors of bacteria (Goal 38 of
SWMP).
13. Survey individual sewage disposal systems (i.e. septic tanks) in Plan Area watersheds
containing streams on the 2020 303(d) list (excluding Missouri River, Goal 39 of SWMP).
Detect and eliminate illicit discharges that are sources of bacteria.
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14. Develop a tabular database and GIS layer of properties that have participated in a sewer lateral
repair program in order to assist with illicit discharge investigations (Goal 40 of SWMP). This
activity directly pertains to bacteria as a pollutant.
15. Maintain an enforcement plan for addressing illicit discharges in order to secure timely
elimination of illicit discharges, including those that are sources of bacteria (Goal 41 of
SWMP).
Please note, information gathered for goals 38, 39, and 40 of the SWMP will also be used to support
bacteria reduction strategies listed in Section 3.3 TMDL Best Management Practices Targeting Bacteria.
3.1.4 MCM #4, Construction Site Stormwater Runoff Control
Under MCM #4, MSD and its co-permittees develop, implement, and enforce a program to reduce
pollutants in any stormwater runoff to their regulated Small MS4 from construction activities that result in
land disturbances greater than or equal to one acre. Reduction of stormwater discharges from a
construction activity disturbing less than one acre is included in the program if that construction activity is
part of a larger common plan of development or sale that would disturb one acre or more.
Each incorporated municipality has the authority for construction permitting and inspection services.
Some co-permittees provide full permitting and inspection services independently, while others have
adopted St. Louis County’s ordinance and contract with St. Louis County Code Enforcement to meet
permitting and inspection needs. While bacteria contributions from land disturbance sites is expected to
be low, the potential for discharges of E. coli from sanitary facilities at construction sites is reduced
through inspections and enforcement. There are eight individual activities implemented under MCM #4,
of which five specifically relate to bacteria through retaining waste on site or by ensuring sediment and
erosion controls are properly installed. Those five activities are as follows:
1. Maintain written procedures and guidance materials for operators to follow (Goal 44 of
SWMP). This activity will help prevent sanitary waste from leaving the site and potentially
entering a water course.
2. Maintain written procedures and guidance materials for permittees to follow (Goal 45 of
SWMP). This activity will address bacteria by requiring development pre-construction planning
and appropriate installation and maintenance of sanitary waste facilities.
3. Maintain written procedures to receive, respond to, and track public inquiries and complaints
(Goal 46 of SWMP). This activity will address bacteria by providing timely responses to
complaints of sanitary waste leaving a site.
4. Maintain written procedures and checklists for permittees to follow during SWPPP inspections
(Goal 47 of SWMP). This activity will address bacteria by ensuring BMPs for sanitary waste
facilities are properly installed and maintained.
5. Inspect land disturbance sites per land disturbance program ordinance (Goal 48 of SWMP).
This activity will address bacteria by ensuring BMPs for sanitary waste facilities are properly
installed and maintained.
3.1.5 MCM #5, Post-Construction Stormwater Management in New Development and
Redevelopment
MSD and its co-permittees require developers to implement appropriate strategies and controls to address
post-construction runoff from new development and redevelopment projects that disturb one acre of land
or more, including projects less than one acre that are part of a larger common plan of development or
sale. MSD and co-permittee ordinances ensure all applicable public and private development projects
involving stormwater management are reviewed and approved by MSD.
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All projects are required to assess existing site conditions and identify sensitive areas and natural
resources on site. The Rules and Regulations require that site designers prepare a site development plan
that adequately protects sensitive areas and natural resources and does not generate unwarranted amounts
of stormwater pollution. This plan may be based on the current version of the Site Design Guidance
document on MSD’s website. Development sites regulated in the MS4 are required to apply strategies that
reasonably mimic predevelopment runoff conditions by reducing runoff volume to calculated
predevelopment levels. MSD requires all stormwater facilities to be provided and designed in accordance
with provisions contained in the “Rules and Regulations and Engineering Design Requirements for
Sanitary Sewer and Stormwater Drainage Facilities,” as amended.
The Bacteria and Nutrient Best Management Practice Strategy Review, conducted by Geosyntec
Consultants and reported in a memorandum dated December 23, 2016 (Appendix B), evaluated MSD’s
ongoing stormwater management facility selection based on bacteria and nutrient reduction effectiveness
and helped characterize BMP implementation to the MEP. This review found that nearly 70% of built or
planned structural facilities in the MS4 area scored high for removal of bacteria. Those structural facilities
included bioretention basins, infiltration facilities, permeable pavements, and ponds. Continued
implementation of these stormwater facilities and enhancements as recommended in the memorandum
will help meet bacteria reduction targets.
Maintenance responsibility for approved post-construction stormwater management facilities belongs to
the owner. MSD’s authority to ensure stormwater facilities are maintained is covered under MSD
Ordinance No. 15048. Owners submit annual reports on facility condition and MSD conducts inspections
of each stormwater facility at least once every three years.
There are eight activities implemented under MCM #5 in the current SWMP, all of which will help to
reduce bacteria contamination of stormwater. Those activities are as follows:
1. Utilize the technology matrix in MSD’s stormwater management toolbox and maintain existing
strategies (Goal 50 of SWMP). This activity will require developments to implement
appropriate strategies and controls to address post-construction runoff, and will result in
implementing activities to the MEP, including those that target bacteria.
2. Identify co-permittees who have implemented supplemental practices to reduce impervious
parking areas and incorporate green infrastructure (Goal 51 of SWMP). This activity will
reduce impervious parking areas and reduce barriers to incorporating green infrastructure into
parking areas, helping to remove bacteria in stormwater.
3. Maintain an optional conceptual review process to provide developers with a plan review
assessment of appropriate strategies and controls to address post-construction runoff (Goal 52
of SWMP). This activity will identify opportunities for water quality protection, including
identifying stormwater facilities that can help remove bacteria early in the project planning
phase.
4. Make the Site Design Guidance document available to provide developers and plan reviewers a
way to implement effective stormwater management controls (Goal 53 of SWMP). This
activity will lead to utilizing effective stormwater facilities, protecting sensitive areas, and help
to remove bacteria from stormwater.
5. Use pre-condition assessment with early-stage project planning which will lead to utilizing
effective stormwater facilities, protecting sensitive areas, and help to remove bacteria from
stormwater (Goal 54 of SWMP).
6. Follow MSD and co-permittee ordinances, as well as MSD Rules and Regulations, which
require developers and plan reviewers to implement appropriate strategies and controls to
address post-construction runoff (Goal 55 of SWMP). Included among those strategies and
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controls, is the use of certain stormwater management facilities that remove bacteria from
stormwater.
7. Follow the plan review process of executing maintenance agreements for the environmental
compliance inspection process in order to ensure long-term operation of stormwater facilities,
including those that remove bacteria (Goal 56 of SWMP).
8. Inspect all water quality stormwater facilities utilizing key performance indicators to
demonstrate compliance (Goal 57 of SWMP). This activity will ensure the long-term operation
of stormwater facilities, including those that remove bacteria from stormwater.
3.1.6 MCM #6, Pollution Prevention/Good Housekeeping for Municipal Operations
Under MCM #6, MSD and its co-permittees implement an operation and maintenance program that
includes a training component and has the ultimate goal of preventing or reducing polluted runoff from
municipal operations. Common municipal operations that are addressed by an Operations and
Maintenance Program include: general housekeeping and operation and maintenance; vehicle/equipment
repair and maintenance operations; vehicle/equipment washing; facility repair, remodeling, and
construction; cleaning and maintenance of roadways, highways, bridges, and parking facilities;
maintenance of parks, green spaces, trails, and landscaping; cleaning and maintenance of drainage
channels, storm sewers, and inlet structures; operation and maintenance of recycling facilities; and, water
quality impact assessment of flood management projects. Written Operation and Maintenance Program
procedures help to ensure pollution controls are properly installed and maintained. Training provided to
staff covers pollution prevention and control techniques that may apply to the municipal operations noted
above, as well as identifying and reporting illicit discharges. There are 12 specific activities included
under MCM #6 in the SWMP, and eight of those help to reduce bacteria in stormwater. Those activities
are as follows:
1. Provide annual training to all MSD and co-permittee employees who work in municipal
operations impacted by stormwater in order to prevent and reduce stormwater pollution from
municipal operations (Goal 58 of SWMP). Training includes information on reporting illicit
discharges such as failing septic systems, which will help to reduce bacteria in stormwater.
2. Install stormwater facilities with the construction of municipal buildings and roadways, where
feasible, for the purpose of providing pollutant controls (Goal 60 of SWMP). Certain facilities
will help remove bacteria from stormwater.
3. MSD and all co-permittees are to maintain a written Operation and Maintenance Program to
ensure stormwater pollution prevention and control methods for municipal operations are
properly installed and maintained (Goal 63 of SWMP). The written Operation and Maintenance
Program template recommends certain activities that address bacteria (e.g., posting pet waste
signs in public parks and maintaining disposal stations, and developing and enforcing
ordinances against illicit discharges) be implemented to the maximum extent practicable, in
order to reduce levels of bacteria generated on property owned and operated by the co-
permittee.
4. MSD and all co-permittees are to maintain a written Operation and Maintenance Program to
prevent and reduce runoff from municipal operations (Goals 65, 66 and 67 of SWMP). The
written program includes guidelines for posting pet waste signs in public parks, control of wild
geese populations near lakes, and stormwater practices for improving the water quality of
runoff, which will help reduce bacteria in stormwater.
5. Maintain written guidelines for MSD to follow when preparing preliminary engineering project
studies for assessing water quality impacts for new flood management projects (Goal 68 of
SWMP). MSD’s guidelines include recommendations for protecting and improving water
quality conditions, which will help reduce bacteria in stormwater.
6. Maintain written Operation and Maintenance Program to assess and mitigate water quality
impacts for new flood management projects (Goal 69 of SWMP). The written Operation and
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Maintenance Program template includes recommendations for protecting and improving water
quality conditions, which will help reduce bacteria in stormwater.
3.2 Project Clear
MSD’s implementation of Project Clear has and will continue to result in reduced bacteria loading to Fee
Fee Creek. Project Clear is a long-term effort by the Metropolitan St. Louis Sewer District (MSD) that
focuses on three categories of work: get the rain out; repair and maintain; and building system
improvements. Get the rain out focuses on preventing excess stormwater from entering the sewer system
through a variety of project types, including downspout disconnections and rainscaping. Repair and
maintain continues the work MSD has done to repair, maintain, and renew the existing sewer system, on a
faster timeline. Building system improvements involves new construction of wastewater management
structures, including deep underground tunnels and above-ground storage tanks.
Project Clear activities meet obligations required under the federal consent decree. Among those
obligations, MSD must eliminate all constructed sanitary sewer overflow outfalls no later than December
31, 2033 8. Other Project Clear strategies that involve sewer inspection, maintenance, and repair and
rehabilitation will reduce occurrences of sanitary sewer overflows as well. The following sections
describe MSD’s work under Project Clear and the federal consent decree that will address bacteria
loading in Fee Fee Creek.
3.2.1 Sanitary Sewer Overflow Control Master Plan
MSD’s SSO Control Master Plan developed in compliance with the consent decree describes specific
measures that will result in the elimination of all constructed SSO outfalls, all known SSOs, building
backups, and/or any activities that are necessary to ensure there is adequate capacity in the sanitary sewer
system to collect, convey, and treat anticipated wet weather flows under current and projected future
conditions. Remedial measures used to address capacity limitations and eliminate bypassing may include
the removal of I/I sources and increases in the capacities of sewer pipes, force mains, and pump stations.
The SSO Control Master Plan is required to eliminate 85% of the constructed SSO outfalls by December
31, 2023. Elimination of up to 15% of the constructed SSO outfalls may occur after December 31, 2023,
but all must be eliminated no later than December 31, 2033.
3.2.1.1 Sewer System Evaluation Survey (SSES)
As part of the SSO Control Master Plan, MSD performed a SSES for the Fee Fee Creek watershed9. The
purpose of the SSES was to identify 1) areas with excessive inflow/infiltration (I/I) which are causing or
contributing to Sanitary Sewer Overflows (SSOs) and Building Backups, 2) known SSOs within the
watershed, 3) physical conditions and design constraints of Pump Stations and force mains that
contribute to SSOs and Building Backups, 4) physical and/or structural conditions of pipes,
manholes, and structures in the Sanitary Sewer System that contribute to SSOs and Building
Backups, 5) sources of I/I determined to have excessive I/I rates, and 6) stormwater cross
connections and discovered unauthorized direct connections.
The SSES identified priority areas of the watershed with excessive I/I which were causing or contributing
to SSOs or building backups. That assessment was based on the following criteria: existence of
constructed SSO outfalls; number of sewer backup insurance claims; number of customer service
8 MSD’s consent decree was amended on June 22, 2018. This amendment extended the construction schedule for
certain combined sewer overflow storage tunnels in the River Des Peres watershed by five years. MSD also agreed
to invest $20 million in green infrastructure in its Lemay Service Area/River Des Peres Watershed.
9 Metropolitan St. Louis Sewer District. 2013. Fee Fee Creek watershed sewer system evaluation survey. Completed
December 31, 2013. 420pp.
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requests; water quality impacts; and I/I rate estimates. Highest priority areas were mapped in the southeast
and northeast portions of the watershed.
Physical/structural condition and design constraints of sanitary sewer infrastructure were also described in
the SSES report. The SSES lists three (3) sanitary pump stations located within the Fee Fee Creek
watershed that were owned and maintained by the District. Of the pump stations mentioned, two have
been decommissioned and one, Fee Fee Master Lift #1 (P-717), mentioned in Section 2.1 Sanitary Sewer
Infrastructure, is still in operation. Between April 27, 2007, and April 27, 2012, there were 95 known
SSOs of which only one was attributed to a pump station, that being Fee Fee Master Lift #1 (P-717).
SSOs at pump stations can occur due to mechanical failure, electrical outage, or excessive wet weather
flows that exceed pump station capacity. During the same time period, there were 246 building backups,
however none of those backups were attributed to pump stations or forcemains. Of the three sanitary
pump stations in Fee Fee Creek watershed that were owned and maintained by the District, one did not
have backup storage capacity or onsite backup power. There are no forcemain design constraints in the
Fee Fee Creek watershed. CCTV investigations of 1,228 sewer reaches comprising approximately 21% of
the sanitary sewers in the watershed were carried out in suspected problems areas (thus may not be
indicative of the entire watershed). Of the sewer reaches that were televised, approximately 46% had
major to moderate structural issues or root intrusion warranting strong or medium attention by MSD.
I/I studies were conducted in higher priority areas of the watershed identified by their potential for
causing or contributing to SSOs or building backups. I/I was attributed to both public and private defects.
Public defects are found on sewers and manholes located on public ground or easement and maintained
by MSD. Private defects are found on private property. Public defects included indirect connections,
mainline defects, manhole cover defects, manhole frame defects, and manhole structure defects. There
were no direct connections of inflow among the public defect findings. Private sources of I/I were the
result of the following defective components: downspouts, cleanouts, laterals, drains (i.e., yard drains,
driveway drains, basement entry drains, foundation drains, etc.), and buildings (including dry traps, open
pipes, and defective plumbing). Overall, most defects in the study were the result of defective manhole
frames, manhole structures, manhole covers, cleanouts, mainlines, and private laterals. Defect categories
that may have the greatest impact on wet weather flows (average flow per defect) associated with overall
I/I included indirect connections, downspouts, manhole covers, and cleanouts.
The SSES resulted in a total of 3,090 defects with an associated flow estimated at 3,875 gallons per
minute (gpm) from both public and private sources. In total, there were 1,005 (32%) private defects with
an associated flow estimated at 1,932 gpm (50%). From the public sewer system, there were 2,085 (68%)
defects with an associated flow estimated at 1,943 gpm (50%). Furthermore, the number of inflow defects
totaled 2,423 (78%) providing an associated flow estimated at 3,276 gpm (85%). Whereas infiltration
defects totaled 667 (22%) providing an associated flow estimated at 599 gpm (15%). The SSES report for
the Fee Fee Creek watershed contains a complete summary of I/I estimated flows and attributed sewer
defects.
3.2.1.2 Master Plan Projects
As a result of an extensive planning process that included the SSES among other reports, 15 SSO Control
Master Plan projects were originally scheduled in the Fee Fee Creek watershed. Appendix A includes a
table with all SSO Control Master Plan projects for Fee Fee Creek watershed. Projects listed in the table
include schedules for I/I reduction related to both public and private sources, sanitary relief and storage,
and other system improvements. Public and private work includes remedial measures to address their
respective defects as described in the previous section. All of this work is usually scheduled ahead of
Master Plan dates to ensure compliance with timelines in MSD’s consent decree.
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Four projects in the SSO Control Master Plan for Fee Fee Creek watershed address cost effective I/I
reduction within the sanitary system. The purpose of I/I reduction projects is to reduce public and private
inflow and infiltration into the sanitary system in order to provide system capacity to convey flow and
reduce SSOs and building backups. Inflow occurs when stormwater enters the sanitary sewer through
direct connections. Sources of inflow can include connections from stormwater sewers, roof drains,
defective laterals and lateral cleanouts, and other drains for yards, driveways, basement entries,
foundations, etc. Infiltration occurs when groundwater enters the sanitary sewer system through cracks
and other openings in defective or deteriorated sewers, or when stormwater cross connections and/or
parallel connections with the sanitary sewer system exist. Cracks or openings may be caused by age
related deterioration, loose joints, installation errors, damage, or root infiltration. During storm events
inflow and infiltration sources influence sewer flows differently, with inflow impacting the sewer
immediately and infiltration impacting the sewer over an extended period of time following the event.
Ten (10) projects focus on sanitary relief. Among these projects, seven (7) included a plan/phase to
eliminate ten (10) total constructed SSO Outfalls BP-491, BP-083, BP-511, BP-086, BP-069, BP-076,
BP-087, BP-068, BP-080, and BP-537. The purpose of sanitary relief is to increase the capacity of the
sewer to handle wet weather peak flows without experiencing surcharging sufficient to cause SSOs,
including causing failure of the largest pump in any pumping station and/or primary power failure to any
pumping station.
One (1) SSO Control Master Plan project was specifically developed for eliminating a single constructed
SSO (BP-078). In total, eight (8) SSO Control Master Plan projects included work to eliminate one or
more constructed SSO outfalls. Combined, a total of eleven (11) constructed SSOs were removed by
these eight (8) projects.
Collectively, the 15 SSO Control Master Plan projects included 19 unique plan/phases. Of these
plan/phases, 15 have been completed, three (3) have their initial designs completed and one (1) phase is
considered under construction and not yet officially complete. The 15 phases which have been completed
addressed private and public I/I reduction, sanitary relief and constructed SSO outfall removal (See
Appendix A). As noted previously, all constructed SSO outfalls in Fee Fee Creek watershed have been
removed as of November 4, 2021.
The remaining Master Plan projects are scheduled for anticipated completion from 2024 through 2025.
These projects in large part focus on providing sanitary relief and will correct defects and eliminate
sources of I/I that deprive the system of capacity where necessary. The status of projects listed in
Appendix A will be submitted with each SWMP Annual Report. Completion of Master Plan projects will
aid in the reduction of bacteria to Fee Fee Creek.
3.2.2 Capacity, Management, Operations, and Maintenance Program
MSD’s Capacity, Management, Operations, and Maintenance (CMOM) Program operates with goal of
maintaining established service levels and minimum performance standards. MSD’s CMOM Program
conducts the following activities:
1. Inspects 280 miles of sanitary sewer by CCTV each year, and annually reports location and number
of miles of sewer pipe inspected.
2. Acoustically inspects all sewers 15 inches or less in the separate system on a six-year cycle. All
sewers that score an acoustic inspection rating of 0 to 5 will be cleaned. Clean all sewers greater than
15 inches and less than or equal to 21 inches in the separate system on a six-year cycle. Clean all
sewers less than or equal to 21 inches in the combined system on a five-year cycle. Clean all sewers
greater than 21 inches as needed. MSD annually reports the number of miles and locations of all
sewer pipes that are acoustically inspected or cleaned.
MSD & MS4 Co-permittees
Fee Fee Creek E. coli TMDL ARAP
21
3. Inspects 15,000 manholes annually and performs manhole frame adjustments as needed (there is no
yearly target for manhole frame adjustments), and performs repairs, rehabilitations, and/or
replacements on all manholes with a condition rating of 4 or 5 within one year of discovery. MSD
annually reports locations and number of manholes inspected, total number of manhole frame
adjustments performed, and manholes that were permanently repaired/rehabilitated/replaced.
4. Permanently repairs, rehabilitates, and/or replaces at least 90 miles of sewer pipe each year (the target
of 90 miles was reduced to 65 miles in 2022), and repairs all acute defects within one year of
discovery. MSD annually reports the locations and number of miles of sewer pipes that were
repaired/rehabilitated/replaced, as well as the locations and number of acute defects that were
repaired.
5. Inspects all 283 pump stations on a risk-based matrix, critical and non-critical. Critical pump stations
are inspected weekly, and non-critical stations are inspected monthly. Overflow Regulation Systems
(ORS) pump stations are inspected monthly. MSD annually reports the number of inspections for
each pump station.
6. Visual inspections and non-destructive testing of force mains. Force mains categorized as critical are
inspected visually each year and by non-destructive testing once every five years. Force mains
categorized as non-critical are inspected visually once every five years. All defects discovered during
inspection and testing are repaired within one year. MSD annually reports locations and numbers of
force main assets in each risk category that have undergone visual inspection, non-destructive testing,
and have been repaired/replaced per risk.
CMOM activities will be carried out within Fee Fee Creek watershed and can be expected to contribute to
reduced bacteria loading. CMOM activities will be reported as required under the MSD’s consent decree
and will not be reported as part of this ARAP. Implementation of BMP #4 in Section 3.3 TMDL Best
Management Practices Targeting Bacteria, however, may help detect the CMOM Program Plan’s impact
on bacteria loading to Fee Fee Creek.
3.2.3 Fats, Oil, and Grease Program
The consent decree also includes requirements for MSD to control fats, oil, and grease (FOG) to ensure
their accumulations are not restricting the capacity of the sewer system and causing sanitary sewer
overflows. Under the FOG Control Program Plan, MSD identifies and inspects commercial
establishments/food service establishments (FSEs) and industrial facilities prone to FOG accumulations.
Facilities located in problem areas with reoccurring grease blockages that result in SSOs or in areas with
collection system defects are inspected on a periodic schedule with greater frequency (i.e., quarterly,
semi-annual, or annual). Routine periodic FSE inspections of FOG equipment are conducted every two to
five years when the sewer is in a moderate to low-risk area. FSE inspection frequency may be greater than
five years in low-risk areas with exceptionally large diameter sewer pipes. Other FSE inspections can
occur in response to FOG related complaints, or more randomly when investigators notice a new facility
while in the field, or if an existing facility has undergone a name change. Within MSD’s service area
there are approximately 4,721 facilities having the potential to discharge significant amounts of FOG into
the sanitary sewer system.
Within Fee Fee Creek watershed, there are 226 active FSEs and 16 that are listed as having been
decommissioned10. Over a three-year period from October 1, 2019, through September 30, 2022, 885 FSE
inspections were performed in the watershed, resulting in 25 enforcement actions. Over this same period,
two (2) sanitary sewer overflows were found to be caused by grease blockages.
FSE inspections and enforcement actions are reported annually under MSD’s consent decree, and thus
will not be reported in this ARAP. Instead, implementation of BMP #4 in Section 3.3 TMDL Best
10 FSE data regarding active and decommissioned establishments was obtained on 11/21/2022.
MSD & MS4 Co-permittees
Fee Fee Creek E. coli TMDL ARAP
22
Management Practices Targeting Bacteria, may help detect the FOG Program’s impact on bacteria
loading to Fee Fee Creek.
3.3 TMDL Best Management Practices Targeting Bacteria
Beyond activities carried out under the SWMP and MSD’ s consent decree, specific TMDL BMPs will be
implemented in order to further reduce the bacteria loading in Fee Fee Creek. These BMPs are
specifically designed to improve the monitoring and management of potential sources of bacteria in the
watershed. With the removal of the last constructed SSO in Fee Fee Creek watershed completed on
November 4, 2021, TMDL BMPs in this ARAP as outlined in Table 6 are scheduled to start in 2024,
accommodating time for the ARAP to be prepared and submitted to MDNR, reviewed, and approved.
Thereafter, activities are scheduled by MS4 operating permit year where applicable and are planned
through 2031, extending beyond the remaining SSO Control Master Plan projects in Fee Fee Creek where
monitoring activities will be imperative to gaining a better understanding of potential in-stream water
quality improvements. In the interim, similar ARAP activities will have already been conducted in the
Fishpot Creek and Creve Coeur Creek watersheds. This will lend valuable experience and other “lessons
learned” which can be harnessed to ensure that effective approaches are implemented not only in Fee Fee
Creek but other watersheds subject TMDL ARAPs.
Among the seven TMDL BMPs listed in Table 6, BMPs will include visual inspections of the storm
sewer to identify potential sources of bacteria (TMDL BMP #2) and subsequent response efforts to
eliminate those sources that have been confirmed (TMDL BMP #3). Currently MSD utilizes crawl crews
and CCTV inspections to inspect and assess the condition of large and small storm sewer systems.
Findings from these inspections will include the location of direct connections into storm sewer mains,
inlets, and manholes. Where private connections are discovered, they will be reported to MSD’s Division
of Environmental Compliance to investigate for and identify sources of E. coli bacteria that feed into the
private storm sewer connections. Based on the findings of the investigations, appropriate action will be
taken to eliminate discovered sources of E. coli bacteria associated with the connection. For instance, this
could be an improperly connected house lateral, septic system, or a drainage area served by a drain that is
populated by pets or livestock. Work pertaining to TMDL BMPs #2 and #3 is currently scheduled through
2031. Data obtained from visual inspections of the storm sewer system, including but not limited to
CCTV and Crawl Crew inspections, conducted under the Fishpot Creek and Creve Coeur Creek bacterial
TMDL ARAPs will be used to evaluate the effectiveness of visual storm sewer inspections overall and
help determine the best methods for this activity in Fee Fee Creek and other watersheds with approved
TMDLs for bacteria. It is anticipated that visual storm sewer inspections will be improved and refined
over time, becoming more effective at identifying and eliminating bacteria sources. While TMDL BMPs
#2 and #3 are planned through 2031, they may be completed ahead of schedule or remain ongoing.
In accordance with MS4 Permit Sections 6.1.I and 6.1.J, TMDL BMPs listed in Table 6 of this
section will be implemented according to the provided schedule only after this TMDL ARAP receives
MDNR’s approval. Therefore, MSD respectfully requests MDNR’s approval of this TMDL ARAP.
Implementation activities in the SWMP and MSD’s consent decree will be carried out according to their
previously determined and ongoing schedules. All TMDL BMPs shall be reviewed and evaluated for
effectiveness at the end of year five of the MS4 permit in order to determine if they should be replaced or
modified.
MSD & MS4 Co-permittees
Fee Fee Creek E. coli TMDL ARAP
23
Table 6. TMDL Best Management Practices Targeting Bacteria in the Fee Fee Creek watershed.
1BMP is based on outcome of the SWMP BMP #39 (fourth term).
2BMP is based on outcome of SWMP BMP #40 (fourth term).
3Denotes period for iterative review of BMP effectiveness. In 2034, there will be a review of TMDL BMPs prior to implementation. Iterative review will also take place at the end of Permit Year 5, which is currently not known for the implementation period.
# BMP Description BMP Purpose
Expected Result
of BMP
Measurable Goals and Milestone Dates
Permit Year 3
2024
Permit Year 4
2025
Permit Year 5
20263 2027 2028 2029 2030
2031 BMP Evaluation Process/Criteria
1
Determine extent of
rehabilitated sewers along
Fee Fee Creek and
tributaries. Compare to in-
stream E. coli data.
Identify extent and percent of
rehabbed sewers within
defined proximity to Fee Fee
Creek and tributaries.
Identify potential
relationships with instream
E. coli and need for sewer
rehabilitation work.
Map and summary table of
rehabbed sewers within
defined proximity to Fee Fee
Creek and tributaries.
Generate map
and summary
table.
Generate map
and summary
table.
Generate map
and summary
table.
Generate map
and summary
table.
Generate map
and summary
table.
Generate map
and summary
table.
Generate map
and summary
table.
Generate map
and summary
table.
Map and summary table developed and updated.
2
Identify potential sources of
bacteria through visual
inspections of the storm
sewer system.
Identify sources of bacteria
to Fee Fee Creek.
Summary of bacteria
findings.
Commence
visual
inspections.
Report findings
from 2024.
Continue visual
inspections.
Report findings
from 2025.
Continue visual
inspections.
Report findings
from 2026.
Continue visual
inspections.
Report findings
from 2027.
Continue visual
inspections.
Report findings
from 2028.
Continue visual
inspections.
Report findings
from 2029.
Continue visual
inspections.
Report findings
from 2030.
Continue visual
inspections.
Summary table with bacteria findings developed.
3
Respond to or eliminate
potential human related
sources of bacteria identified
through visual inspections of
the storm sewer systems.
Reduce bacteria loading to
Fee Fee Creek.
Summary of response
actions.
Respond to
bacteria findings
and eliminate
illicit discharges
identified during
visual
inspections.
Report 2024
response actions.
Continue to
respond to
bacteria findings
and eliminate
illicit discharges
identified during
visual
inspections.
Report 2025
response actions.
Continue to
respond to
bacteria findings
and eliminate
illicit discharges
identified during
visual
inspections.
Report 2026
response actions.
Continue to
respond to
bacteria findings
and eliminate
illicit discharges
identified during
visual
inspections.
Report 2027
response actions.
Continue to
respond to
bacteria findings
and eliminate
illicit discharges
identified during
visual
inspections.
Report 2028
response actions.
Continue to
respond to
bacteria findings
and eliminate
illicit discharges
identified during
visual
inspections.
Report 2029
response actions.
Continue to
respond to
bacteria findings
and eliminate
illicit discharges
identified during
visual
inspections.
Report 2030
response actions.
Continue to
respond to
bacteria findings
and eliminate
illicit discharges
identified during
visual
inspections.
Summary table with response actions developed.
4
Assess E. coli data collected
by MSD in previous year and
evaluate loading and trends.
Track E. coli levels and
bacteria loading.
Summary table with E. coli
measurements, loading rates,
and trends.
Summarize 2023
E. coli loading
and trend.
Summarize 2024
E. coli loading
and trend.
Summarize 2025
E. coli loading
and trend.
Summarize 2026
E. coli loading
and trend.
Summarize 2027
E. coli loading
and trend.
Summarize 2028
E. coli loading
and trend.
Summarize 2029
E. coli loading
and trend.
Summarize 2030
E. coli loading
and trend.
Summary table with E. coli measurements,
loading rates, and trend developed and updated.
51
Summarize survey data from
inspections of known
individual sewage disposal
systems in Fee Fee Creek
watershed.
Track properties that may be
a potential source of bacteria
to Fee Fee Creek due to
improper operation of an
individual sewage disposal
system.
Map and list of inspected
properties with an individual
sewage disposal system that
may be a potential source of
bacteria to Fee Fee Creek.
Develop results-
based map and
list of properties
with individual
sewage disposal
systems
inspected by
DEC.
None None None None None Develop results-
based map and
list of properties
with individual
sewage disposal
systems
inspected by
DEC.
None Results based map and list of properties with an
individual sewage disposal system inspected by
DEC developed.
62
Update database of
properties that participated in
a sewer lateral repair
program in Fee Fee Creek
watershed.
Track improvements to
problematic infrastructure
and elimination of potential
sources of bacteria.
Have a database of properties
that participated in a lateral
repair program.
Develop map
and list of
properties.
None None None None None Develop map
and list of
properties.
None Map and list of properties with repaired sewer
laterals developed.
7
Summarize maintenance of
individual sewage disposal
systems documented by
MSD’s Hauled Waste
Program for Fee Fee Creek
watershed.
Have a list of properties that
maintain their individual
sewage disposal system.
Develop a list of properties
that maintain their individual
sewage disposal system.
Obtain 2023
records from
Hauled Waste
Program, add to
list, and report.
Obtain 2024
records from
Hauled Waste
Program, add to
list, and report.
Obtain 2025
records from
Hauled Waste
Program, add to
list, and report.
Obtain 2026
records from
Hauled Waste
Program, add to
list, and report.
Obtain 2027
records from
Hauled Waste
Program, add to
list, and report.
Obtain 2028
records from
Hauled Waste
Program, add to
list, and report.
Obtain 2029
records from
Hauled Waste
Program, add to
list, and report.
Obtain 2030
records from
Hauled Waste
Program, add to
list, and report.
List of properties that maintain their individual
sewage disposal system developed.
MSD & MS4 Co-permittees
Fee Fee Creek E. coli TMDL ARAP
24
4.0 Evaluation
Activities described in this TMDL ARAP will target bacteria sources in Fee Fee Creek and aim to reduce
the overall bacteria load contributing to its impaired status. All activities will be carried out through
implementation of the SWMP, Project Clear and the federal consent decree, or as scheduled in Section
3.3 of this document, TMDL Best Management Practices Targeting Bacteria.
TMDL BMPs listed in Section 3.3 of this document will be implemented according to the schedule found
in Table 6. With the first efforts completed by the Fishpot Creek bacteria TMDL ARAP and others
commencing prior to this watershed, opportunities for “lessons learned” exist. Outcomes of earlier efforts
accomplished in those watersheds will be considered for implementation into this ARAP, either as a
modification to a proposed activity or an additional activity. Such changes to this ARAP schedule could
occur either prior to, or after its commencement, and would be subject to MDNR approval.
TMDL BMPs #2 and #3 are scheduled through 2031 but depending on lessons learned in ARAPs that
were implemented earlier, both BMPs may be completed ahead of schedule or remain ongoing in order to
maximize the effectiveness of visual storm sewer inspections at identifying and eliminating sources of
pathogens. Each TMDL BMP shall be reviewed and evaluated for effectiveness as described earlier to
determine if they should be replaced or modified in order to achieve further progress towards reducing the
bacteria load to Fee Fee Creek. TMDL BMP effectiveness will be largely based on water quality data as
evaluated under TMDL BMP #4.
In line with MS4 Permit Section 6.1.C, implementation of the Fee Fee Creek E. coli TMDL ARAP will
be completed as soon as practicable but is anticipated to span years or even multiple permit terms.
MSD & MS4 Co-permittees
Fee Fee Creek E. coli TMDL ARAP
25
Appendix A
SSO Control Master Plan Projects in Fee Fee Creek Watershed
MSD & MS4 Co-permittees
Fee Fee Creek E. coli TMDL ARAP
26
Project Name* Plan/Phase Project Description**
Commence -
Complete
Construction
Fee Fee Trunk Sewer Relief
(SKME-002) Master Plan Remove SSO 1/14/2019 -
9/27/2019
FF-02 Fee Fee - Alan
Shepard I-270 Sanitary
Relief Phase V
Master Plan
Construct 2,390 feet of 8-inch to 36-inch diameter sewers.
Eliminate two Constructed SSOs (BP-083 and BP-511) and a wet
weather pump station.
5/13/2014 -
4/11/2016
FF-04 Quiet Village
Sanitary Relief Master Plan Construct 2,180 feet of 8-inch to 15-inch sanitary sewer. Eliminate
constructed SSO Outfall BP-086.
5/15/2017 -
6/4/2018
FF-07 Fee Fee Creek
Sanitary Relief
(Meadowside Dr to Willow
Brook Dr)
Master Plan Construct 3,700 feet of 8-inch to 24-inch sanitary sewer and eliminate
constructed SSO Outfall BP-069.
9/11/2020 -
11/4/2021
FF-11 Fee Fee Creek
Sanitary Relief Master Plan
Construct 4,150 feet of 8-inch to 18-inch sanitary sewer, from 1876
Woodhollow drive to Progress Parkway. Part of project to be built by
the City of Maryland Heights, as part of a road improvement project.
7/11/2014 -
7/25/2016
FF-15 McKelvey/R.R. to
Adie Sanitary Relief Phase
III
Master Plan
The third and final phase of a multi-phase project. This phase consists
of the construction of 4,700 feet of 8-inch to 42-inch sanitary sewer
south of Schuetz Road.
8/1/2014 -
12/5/2016
FF-16 Schuetz -
Meadowside to Page
Sanitary Relief
Master Plan
Construct 6,114 feet of 8-inch to 30-inch sanitary sewer, and 5,735
feet of 24-inch to 42-inch pipe in tunnel. Eliminate constructed SSO
Outfall BP-076.
2/23/2018 -
8/5/2021
FF-18 Villa dorado -
Lackland - Page Sanitary
Relief (Adie Rd to Villa
Dorado Dr)
Master Plan
Construct 2,093 feet of 8-inch to 24-inch sanitary sewer, and 2,683
feet of 21-inch to 24-inch pipe in tunnel. Eliminate constructed SSO
Outfall BP-087.
2/25/2019 -
9/11/2020
Forest Brook Sanitary Relief
(SKME-003 AND SKME-
016) Rehabilitation & I/I
Reduction
Master Plan Remove private I/I sources from sanitary sewers. 10/13/2014 -
3/18/2019
Public I&I Rehabilitate Public Sewers to Reduce I&I 7/25/2015 -
3/18/2019
Priv. I&I
Reduction Private I&I 10/13/2014 -
9/8/2015
Galaxy I/I Reduction
Master Plan Rehabilitate 7,000 feet of sewer, 100 manholes, and connections.
Eliminate constructed SSO Outfall BP-491.
5/24/2013 -
10/22/2013
Public I&I Rehabilitate Public Sewers to Reduce I&I 5/24/2013 -
10/22/2013
SSO
Removal 2/19/2014
Lindbergh Sanitary Relief
(Meadowside Dr to N
Lindbergh Blvd)
Master Plan Construct 2,760 feet of 12-inch to 18-inch sanitary sewer. 2/21/2024 -
8/24/2025
McKelvey A AND B
Sanitary Relief Master Plan
Construct 7,500 feet of 18-inch to 21-inch diameter sanitary relief
sewers, rehab 31 laterals, disconnect 8 roof drains, 43 areas drains, &
9 sump pumps. Eliminate three constructed SSOs
(BP-068, BP-080, BP-537).
3/22/2013 -
10/9/2014
MSD & MS4 Co-permittees
Fee Fee Creek E. coli TMDL ARAP
27
Project Name* Plan/Phase Project Description**
Commence -
Complete
Construction
North Fee Fee Creek I/I
Reduction (I-270 and Creve
Coeur Mill Rd)
Master Plan
Rehabilitate with CIPP lining approximately 90,000 feet of 8-inch to
12-inch sanitary sewer pipe. Rehabilitate approximately 450
manholes. Repair approximately 450 service connections. Allow for
approximately 9 point repairs.
11/26/2022 -
3/29/2024
Public I&I Rehabilitate Public Sewers to Reduce I&I 11/26/2022 -
3/29/2024
Schuetz Road Sanitary
Relief (Forest Brook Ln to
Sunny Wood Ct)
Master Plan Construct 1,033 feet of 8-inch to 15-inch sanitary sewer. 3/22/2022 -
10/27/2022
Woodhollow I/I Reduction
(I-270 and Page)
Master Plan
Rehabilitate with CIPP lining approximately 32,100 feet of 8-inch to
12-inch sanitary sewer pipe. Rehabilitate approximately
185 manholes. Repair approximately 400 service connections. Allow
for approximately 4 point repairs.
1/8/2019 -
6/11/2021
Public I&I Rehabilitate Public Sewers to Reduce I&I 1/8/2019 -
6/11/2021
* Status updates will be provided for each Master Plan project listed in Appendix A and submitted annually with the SWMP
Annual report.
** Project description may change during the various project stages and may only describe latest phase.
MSD & MS4 Co-permittees
Fee Fee Creek E. coli TMDL ARAP
28
Appendix B
Bacteria and Nutrient Best Management Practices Strategy Review
2009 East McCarty Street, Suite 1
Jefferson City, Missouri 65101
PH 573.443.4100
FAX 573.443.4140
www.geosyntec.com
Memorandum
Date: December 23, 2016
To: Jay Hoskins, Metropolitan St. Louis Sewer District
From: Avery Blackwell, P.E., Brandon Steets, P.E., Scott Struck, P.E., Dan
Pankani, P.E. Geosyntec Consultants
Eric Dove, David Carani, HDR
Subject: Bacteria and Nutrient Best Management Practice Strategy Review
Geosyntec Project: MOW5165E Phase 90
Attachments: Attachment A - BMP Evaluation Results
Recent actions by the Missouri Department of Natural Resources (MDNR) will impact how the
Metropolitan St. Louis Sewer District (MSD) administers their stormwater management
program. These actions include publication of the Missouri Nutrient Loss Reduction Strategy 1,
completion of Escherichia coli (E. coli or bacteria) total maximum daily loads (TMDLs) for four
streams in the St. Louis area 2, and renewal of the statewide small municipal separate storm sewer
system (MS4) general permit (MOR-040000). Central to each of these actions is the requirement
for MS4 programs to implement best management practices (BMPs) via an iterative process to
reduce the discharge of pollutants into the MS4 to the maximum extent practicable (MEP).
The purpose of this memo is to briefly outline these recent MDNR actions and potential MS4
program impacts, generally characterize MSD’s existing structural and non-structural BMPs for
bacteria and nutrients relative to the state of the practice and other MS4 programs, and
recommend actions that MSD could pursue to further identify areas to enhance BMP
implementation. The results of this review are intended to help MSD characterize MEP for
controlling bacteria and nutrients in stormwater runoff.
1 http://dnr.mo.gov/env/wpp/mnrsc/docs/nlrs-strategy-2014.pdf 2 TMDLs for Coldwater Creek, Creve Coeur Creek, Fishpot Creek, and Watkins Creek were approved by EPA on
July 13, 2016.
Bacteria and Nutrient BMP Strategy Review
December 23, 2016
Page 2
MOW5165E | St. Louis | 2016(1223)_MSD_BMP_Evaluation_Memo
REGULATORY CONTEXT
As mentioned above, the Missouri Nutrient Loss Reduction Strategy (Nutrient Strategy), recently
approved bacteria TMDLs, and the newly-issued small MS4 general permit each require MSD to
evaluate current approaches for defining MEP. Evaluating approaches for defining MEP for
controlling bacteria and nutrient levels in a comprehensive fashion will assist MSD in
determining how best to define MEP. A brief description of these MDNR initiatives and their
impact on MSD’s stormwater management program are outlined below.
In December 2014, MDNR finalized the Nutrient Strategy which outlines a set of recommended
actions that MS4s and other nutrient sources could implement to reduce nutrient loads to the
Gulf of Mexico. Available data (provided by MSD) suggest that MS4s are a relatively minor
source of nutrients to the Gulf and that additional data are needed to characterize urban
stormwater loads. The Nutrient Strategy also acknowledges the role of state-mandated funding
limitations for stormwater programs, and the need for an interactive, efficient, and cost-effective
approach to address MS4 nutrients. To that end, the Nutrient Strategy identifies several actions
that MS4 agencies should complete over a five-year period (2015-2019) to better characterize
their programs and define MEP in the context of nutrient reductions. These include the
following:
• From 2015 to 2017, review public involvement and education programs and material and
make recommendations for enhancements to implement in 2018-2019 consistent with
available funding.
• From 2015 to 2019, review programs and identify appropriate structural and non-
structural BMP enhancements to implement in 2020 and beyond consistent with available
funding. At a minimum, MS4 agencies should consider how low-impact development
practices might improve nutrient management effectiveness.
In January 2015, MDNR finalized E. coli TMDLs for four streams in the St. Louis area; EPA
subsequently approved the TMDLs in July of 2016. These TMDLs identified MSD and several
of the MS4 co-permittees as point source contributors of bacteria in the watersheds. As MDNR
stated in the “Reasonable Assurance” section of each TMDL, “The wasteload allocations for
MS4s will be implemented through the NPDES MS4 permits with the ultimate goal to employ an
iterative process using BMPs to the MEP, assessment, and refocused BMPs to the MEP, leading
toward attainment of water quality standards (64 FR 68753)”. In the implementation plan, which
accompanied each TMDL, MDNR discussed MS4 stormwater management plan requirements to
address the six minimum control measures (MCM), and reiterated that BMPs and programs
developed under the MCMs are expected to result in bacteria reductions from the MS4 area.
Bacteria and Nutrient BMP Strategy Review
December 23, 2016
Page 3
MOW5165E | St. Louis | 2016(1223)_MSD_BMP_Evaluation_Memo
Since 2013, MDNR has also been working closely with stakeholders, including MSD, to revise
and reissue the statewide Phase II MS4 general permit. The permit was issued by MDNR on
October 1, 2016. The permit includes clarifying language that MS4 discharge limits are defined
as BMPs to the MEP. More specifically, Section 1.4.1 of the permit states, “The permittee shall
implement Best Management Practices (BMPs) via an iterative process to reduce the discharge
of pollutants to the Maximum Extent Practicable (MEP) into the MS4 for the goal of attainment
with Missouri’s Water Quality Standards…” The permit also includes new requirements for MS4
that are subject to a TMDL. These requirements include developing a TMDL Assumptions and
Requirements Attainment Plan (ARAP) that includes, among other things, a process to identify
specific BMPs to address TMDL pollutants, prioritized actions, and an implementation schedule.
STRUCTURAL BACTERIA AND NUTRIENT BMP EVALUATION
Structural BMPs Evaluated
MSD requires new and redevelopment projects to submit a Stormwater Management Facilities
BMP Operation and Maintenance Design Report and Plan for approval. According to MSD’s
Small MS4 2015-16 Annual Report (Annual Report), since implementation of these new water
quality BMP requirements in October 2006, 1,286 projects representing 4,516 BMPs have been
constructed, permitted for construction, or are under review by MSD’s Planning Division.
According to the Annual Report, bioretention (48%) was by far the most common BMP
implemented (Figure 1).
Bacteria and Nutrient BMP Strategy Review
December 23, 2016
Page 4
MOW5165E | St. Louis | 2016(1223)_MSD_BMP_Evaluation_Memo
Figure 1. Post-Construction BMPs Built, Permitted for Construction, or Under Review as of 6/16/2016 (from the
Annual Report). Of the 4,516 BMPs, nearly half were bioretention
In addition to the structural BMPs identified in the Annual Report (Figure 1), this evaluation
included three common Post-Construction Ordinances: stream buffers, tree preservation, and
impervious area reduction. Also, two advanced structural BMPs designed specifically for
treating bacteria and nutrients were evaluated. These advanced structural BMPs included
enhanced biofilters 3 and subsurface flow wetlands 4.
3 Enhanced biofilters are defined here as vegetated media filters (or bioretention with underdrains) that incorporate
the following design enhancements that have been shown to improve bacteria reduction relative to standard
biofilters:
• Media amendments such as biochar and coconut coir that have been shown to enhance bacteria removal;
• Vegetation that is shown to enhance bacteria removal and support media aeration while reducing potential for
short circuiting or underdrain clogging;
• Outlet control for enhanced contact time; and
• A saturated zone. 4 Subsurface flow wetlands are engineered, below-ground horizontal flow treatment wetlands that include many of
the natural treatment processes of surface flow constructed wetlands as well as the filtration mechanisms of media
filters. Water flows through a granular matrix, which typically supports the growth of emergent wetland vegetation
on the surface.
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Relative Benefit Rankings for Structural BMPs
To evaluate bacteria and nutrient reduction effectiveness of ongoing structural BMP
implementation, the BMP categories were compared using a relative scoring system based on
weighting factors derived from previous BMP implementation planning experience, along with
feedback from MSD. Table 1 identifies the weighting applied to each benefit category and
briefly describes the approach to score the BMPs.
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Table 1. Approach for Scoring and Weighting Benefits.
Benefit
Group Benefit Category Weighting Scoring Approach
Target
Pollutant
Benefits
E. Coli Treatment 30% First, benefits from pollutant concentration reductions will
be calculated based on median effluent concentrations from
the International Stormwater BMP database 5, along with
statistical results showing whether the removal was
significant (e.g. non-parametric hypothesis tests, either the
Mann-Whitney rank sum test or the Wilcoxon signed-rank
test). Then these scores will be modified to include the
pollutant reductions resulting from volume reduction.
Nitrite (NO2) and
Nitrate (NO3)
Nitrogen
Treatment
15%
Total Phosphorus
Treatment 15%
Additional
Benefits
Other Water
Quality Parameter
Treatment
15%
Based on significant reduction of other important water
quality parameters (e.g., total suspended solids, metals,
chloride) as reported in the Boston BMP Guidance
Document 6.
Flood
Management 10%
The relative ability to decrease flood risk by reducing peak
flow rates and/or volume reduction based on the Boston
BMP Guidance Document.
Habitat/
Environmental
Improvements
7%
Improvement and protection of wetland and riparian
enhancement/ creation evaluated by best professional
judgment.
Community
Enhancements 8%
Based on three factors: (1) Enhancement/creation of
recreational and public use areas, (2) Educational
opportunities, or (3) Aesthetic benefits evaluated by best
professional judgment.
Since the focus of this memorandum is evaluating BMP selection based on water quality
performance for bacteria and nutrients, benefits associated with the treatment of those target
pollutants were grouped and assigned the highest weighting factor. Because there are TMDLs
already in effect for bacteria in the St. Louis area, the E. coli weighting factor was higher than
the nutrients factor. The scoring of target pollutant benefits was performed quantitatively based
on the measured inflow and outflow concentrations for all BMPs that met data quality and
5 Geosyntec Consultants, Inc., Wright Water Engineers, Inc., International Stormwater BMP Database,
Manufactured Devices Performance Summary Report. July 2012. and International Stormwater Best Management
Practices (BMP) Database Pollutant Category Statistical Summary Report Solids, Bacteria, Nutrients, and Metals
http://www.bmpdatabase.org/ 6 Boston Water and Sewer Commission, Stormwater Best Management Practices: Guidance Document, prepared by
Geosyntec Consultants. January 2013.
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quantity criteria 7 from the International Stormwater BMP Database5. The scoring guidance for
the target pollutants is defined in Table 2. The analysis of the target pollutant benefits and the
benefit score for each post-construction structural BMP/Target Pollutant combination 8 is
reported in Table A-1.
Table 2. Target Pollutant Benefit Scoring Guidance for Water Quality Benefits for BMPs.
Score Target Pollutant Benefit
3 High pollutant removal
2 Medium pollutant removal
1 Low or no pollutant removal
In addition to treating stormwater for the target pollutants, the BMPs were evaluated for other
benefits (Table A-2). These other benefits included: 1) reduction of other important water quality
parameters (e.g., TSS/sediments and metals), 2) ability to decrease flood risk by reducing peak
flow rates and/or volume reduction, 3) improvement and protection of wetland and riparian
enhancement/creation, and 4) community enhancements and opportunities. The weighting
factors for these additional benefits reflect their relative significance to MSD, while still
recognizing the important benefits that they could provide. The scoring of the additional benefits
was performed qualitatively based on the Boston BMP Guidance Document and best
professional judgment as defined in Table 3. The analysis of the additional benefits and the
benefit score for each BMP/additional benefit combination is reported in Table A-2.
7 To be included in this category-level summary, at least three BMP studies must be included in the BMP category,
with each BMP study having influent and effluent data for at least three storms for the pollutant of interest. 8 Post-construction ordinances and advanced structural BMPs do not have reported effluent concentrations in the
International Stormwater BMP database and therefore were not included in the Table A-1 analysis.
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Table 3. Scoring Guidance for Additional Benefits of BMPs.
Score Other Water
Qualitya Flood Management Habitat/
Environmental Communityb
3
High in both
sediment and
metals reduction
High volume and
peak flow reduction
Significant
portion of BMP
creates habitat
BMP provides high potential
for all two to three
community benefits
2
Medium sediment
and metals
reduction
Medium volume and
peak flow reduction
Some portion of
BMP creates
habitat
BMP provides medium
potential for two community
benefits
1
Low or no
sediment and
metals reduction
Low or no volume
and peak flow
reduction
Small amount or
no of habitat
created
BMP provides low or no
potential for two community
benefits
a. Chloride was also considered for evaluation in the “Other Water Quality” category; however, only
limited performance data exists for chloride and little or negative removal is shown for those BMPs
with data. Therefore, chloride was excluded in the scoring. b. Community benefits include enhancement/creation of public use areas; educational opportunities;
and community aesthetics.
Scores for each benefit category, as described above, were multiplied by their weighting factors
(Table 1) and a combined benefit score for each BMP 9 was calculated and reported in Table A-3.
The BMPs were then ranked according to their scores and the results are summarized in Table 4.
9 This table also includes scores for target pollutant benefits for post-construction ordinances and advanced
structural BMPs based on expected performance relative to similar BMP types determined using best professional
judgment.
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Table 4. Distribution of BMPs Used within the MSD Service Area and Benefits Ranking.
Rank BMP Score
% of BMPs
Built or
Planned
1 Infiltration BMPs 2.9 1%
2 Subsurface Flow Wetlands 2.8 NA
3 Ponds 2.6 1%
4 Enhanced Biofilters 2.5 NA
5 Bioretention 2.4 48%
5 Permeable Pavement 2.0 18%
7 Surface Sand Filters 1.8 0.04
8 Underground Sand Filters 1.8 1%
9 Underground Manufactured Filters 1.5 0.01
10 HDS Units 1.5 6%
11 Cisterns 1.4 0.01
12 Impervious Area Reduction 1.4 NA
13 Engineered Swales 1.3 4%
14 Tree Preservation Ordinance 1.2 NA
14 Stream Buffer 1.2 NA
Relative Cost Rankings for Structural BMPs
To provide estimates of the local capital and annual maintenance costs of the post-construction
structural BMPs and evaluate the relative cost ranking for the post-construction structural BMPs
and ordinances and advanced structural BMPs, the following cost analysis was conducted. The
cost estimations presented in this section are based on estimates of probable capital and
maintenance costs per capture (treatment) of runoff from one acre of drainage area. The costs
were computed by developing a cost estimation procedure that uses unit cost information from
literature for capital and maintenance costs to create curves (cost per volume treated translated
into cost per tributary area treated) for stormwater BMPs. Example unit cost items include:
• Mobilization
• Demolition
• Clearing & Grubbing
• Dewatering
• Excavation
• Haul/Dispose of Excavation Material
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• Rough and Finished Grading
• Pipe Material (primarily underdrain)
• Soil Media / Planting Media
• Other Bulk Material (pea gravel,
clean-washed gravel, base course
gravel and bedding material)
• Pavement/Concrete/Curbs
• Mulch
• Vegetation
Because there are many factors that affect the capital costs of structural BMPs besides the
treatment volume, such as development type (new development, redevelopment, retrofit), native
soil infiltration rate, site slope, pretreatment requirements, existing infrastructure, and large
event/overflow safety, a range of costs is included as part of the cost estimation. While the costs
for the effort were calculated on a national scale using literature and bid tabs from across the
country, an approach was developed using Bureau of Labor Statistics data for stormwater
construction equipment, material and labor to tailor estimated costs to the St. Louis region. Other
factors that can often influence costs such as: land acquisition, project purpose (e.g.,
demonstration project), regulatory and permitting requirements, utility conflict resolution,
design, union/non-union rates, and level of experience of designers and contractors were not
included as a part of the cost estimation. The three-step cost estimation approach is briefly
summarized below as follows:
• Step 1: Size BMPs – assume a 1-acre drainage area and use the 1.14-inch design storm
for the study area to compute the design volume of runoff required for each BMP for a 1-
acre residential (typically low estimate because of lower impervious surface density) and
1-acre commercial lot (typically higher estimate because of greater impervious surface
density requiring a larger treatment volume and therefor larger treatment facility).
• Step 2: Apply Cost Curve –determine cost curves function for each scenario and obtain
low/high cost estimation range for BMPs to meet design requirements. Report cost
estimate as a range comprised of the low residential estimate (assumed to be 35% site
imperviousness) and the high commercial estimate (assumed to be 65% site
imperviousness) to effectively bracket costs. Of note, if impervious density is greater,
than a higher cost would be needed to capture and treat the associated design volume.
• Step 3: Apply Cost Regionalization and Inflation Adjustment – Convert national
itemized unit cost estimates from RS Means, built projects, bid tabs, and other data
sources, using stormwater construction specific regional cost adjustment factor based on
Bureau of Labor Statistics data for St. Louis from Step 1. An inflation adjustment factor
was applied as needed to obtain 2015 estimates (the most recent complete year for
Bureau of Labor Statistics data).
The result of applying the three-step cost estimation approach is shown in Table 5.
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Table 5 Estimates of Probable BMP Construction and Maintenance Costs per Acre of Drainage Area Treated.
Post-Construction BMPS
Initial Capital Cost Estimate
Range*
(Treatment for a 1-acre site)
Annual Maintenance Cost
Estimate Range
(Per System)
Low High Low High
Bioretention $ 10,800 $ 25,400 $ 900 $ 4,000
Infiltration BMPs $ 4,800 $ 29,000 $ 700 $ 4,400
Engineered Swales $ 3,500 $ 17,600 $ 200 $ 1,300
Permeable Pavement $ 8,200 $ 27,600 $ 800 $ 3,100
Cisterns $ 12,400 $ 21,600 $ 200 $ 700
Ponds $ 9,000 $ 30,800 $ 700 $ 4,900
Surface Sand Filters $ 14,400 $ 38,800 $ 900 $ 3,200
Underground Sand Filters $ 17,000 $ 50,200 $ 1000 $ 3,700
Underground Manufactured
Filters $ 12,200 $ 39,300 $ 1,100 $ 4,600
HDS Units $ 14,100 $ 42,200 $ 1,000 $ 3,700
*Cost curves are not on a per acre basis as many costs are necessary for the first unit of BMP.
Subsequent/additional costs may not be linear and may not have a one to one relationship with area.
Approximate volume of treatment for the 1-acre site was about 1,450-2,700 ft3. Sizing for cost
estimation is based on an assumed volumetric capture (about one inch) but does not include achieving a
required level of performance.
To rank the structural BMPs, the average capital and maintenance costs were computed and
BMPs were ranked and placed into tiers representing similar costs between BMPs. The relative
capital cost and maintenance scores for each BMP were assessed for an estimated 20-year life
cycle cost to capture the long-term maintenance cost estimates along with initial capital costs.
The BMPs were then ranked according to their scores. The results are summarized in Table 6.
A lack of data on post-construction ordinances and the advanced structural BMPs resulted in
these management strategies receiving no cost score to prevent comparison and potential biases
between BMPs of known and unknown costs.
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Table 6 Rankings Based on Estimates of Probable Capital and Maintenance Costs
Tier BMP
Estimated Cost
Score
1
Engineered Swales 3.0
Cisterns 2.5
Bioretention 2.4
Infiltration BMPs 2.4
Ponds 2.3
Permeable Pavement 2.2
2
Underground Manufactured
Filters 1.6
Surface Sand Filters 1.6
HDS Units 1.4
Underground Sand Filters 1.0
3
Stream Buffer NA
Tree Preservation Ordinance NA
Impervious Area Reduction NA
Enhanced Biofilters NA
Subsurface Flow Wetlands NA
Not applicable (NA) was assigned to BMPs that did not have available cost
information.
Site-Specific Considerations for Using Structural BMP Rankings
An important component of post-construction runoff control programs, relative to the iterative
process of removing pollutants to the MEP, is the process for accounting for site-specific
feasibility issues and constraints. This issue is typically addressed in BMP technical guidance
manuals for new and redevelopment (and possibly in stormwater ordinances as well), and each
MS4 permittee or jurisdiction may choose to exercise their authority and level of
prescriptiveness differently. As one example, the Orange County Technical Guidance
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Document 10 establishes detailed infeasibility criteria for each BMP type. Below are some very
basic infeasibility criteria examples and their implications for BMP suitability relative to the
BMP ranking established herein:
• Infiltration constraints (e.g., tight soils and shallow bedrock or groundwater that would
prohibit infiltration based options) – At sites where such constraints exist, ponds,
subsurface flow wetlands, and enhanced biofilters are treatment-only BMPs that are
acceptable alternatives based on demonstrated pollutant removal performance.
• Limited space for BMP footprint (e.g., steep slopes within the site) – In this case,
permeable pavement is an acceptable and effective option to retain/treat stormwater
where the BMP area is incorporated into the development footprint. Also, enhanced
biofilters typically have a larger treatment capacity (i.e., can be built smaller, while still
treating the same design flowrate or volume) than similarly sized, higher ranked BMPs.
• Large design volumes requiring treatment (e.g., significant impervious area within the
site) – This constraint could make some BMP types infeasible unless implemented in
combination with others (e.g., large cisterns may be impractical). In general, project
applicants should be encouraged to consider the benefits of BMP combinations (e.g.,
treatment trains, distributed BMPs), where appropriate.
Finally, and related to both MEP and necessary components of any BMP technical guidance
manual, since this BMP ranking evaluation assumed all BMP types are sized the same, clear
design storm guidance should accompany any BMP selection guidance that is provided to project
applicants.
NON-STRUCTURAL BACTERIA AND NUTRIENT BMP EVALUATION
To better understand the extent to which non-structural BMPs are currently being implemented
to target bacteria and nutrients, stormwater program managers from MSD and seven other MS4
communities were surveyed. These communities were selected based on their geographic
distribution and ease of obtaining information. Furthermore, although MSD is a Phase II MS4,
both Phase I and II communities were included in the survey. Both Phase I (large) and II (small)
systems were surveyed since MSD’s stormwater system is more comparable in size to Phase I
communities; however, it is controlled under Phase II regulations and permit requirements. The
number of MS4 communities surveyed in each EPA region included:
10 County of Orange, 2013. Technical Guidance Document (TGD) for the Preparation of Conceptual/Preliminary
and/or Project Water Quality Management Plans (WQMPs). December 20, 2013.
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• MSD (EPA Region 7 – Phase II Community)
• EPA Region 7 – Phase I Community (2)
• EPA Region 7 – Phase II Community (1)
• EPA Region 4 – Phase I Community (1)
• EPA Region 4 – Phase II Community (1)
• EPA Region 5 – Phase II Community (2)
Program managers were presented with a list of potential bacteria and nutrient BMPs that could
be implemented under each of the six MCMs required by Phase II MS4 regulations. These BMPs
were developed from suggestions presented in the literature 11 and best professional judgment
(see Table A-5 for the list of BMPs). Program managers were asked to identify BMPs from the
list that are currently being applied within their system. It should be noted that the list of BMPs
was not intended to be all-encompassing. Rather, it reflects those BMPs most commonly
considered to be effective for managing bacteria and nutrients
For those BMPs being applied, the managers were then asked to qualitatively assess the degree
to which each is implemented using the following categories:
• High (green) – BMP is used with active management, measurement, or tracking.
• Medium (yellow) – BMP implemented but with limited measurement or tracking
measurement.
• Low (red) – BMP implemented intermittently but few to no measurements or tracking.
• None (blank) – BMP unused or unknown.
To assist in making meaningful comparisons between the qualitative assessment results, each
community response was converted to a relative score (high = 3, medium = 2, low = 1, none =
0). Converted response scores were then summed and standardized for each BMP category to
develop a normalized implementation score that ranges from 0 to 1. The normalized
implementation scores serve to represent the degree to which each BMP is implemented across
the surveyed communities. For a given BMP category, values near 0 indicate that few of the
surveyed communities use the BMP with limited implementation; values near 1 indicate that
most surveyed communities use the BMP with active implementation. For this evaluation,
normalized community scores were interpreted using the following scale:
11 Urban Water Resources Research Council (UWRRC). 2014. Pathogens in Urban Stormwater Systems.
Environmental and Water Resources Institute. American Society of Civil Engineers.
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• Less than or equal to 0.4 – Limited implementation. The BMP may not be applicable to
or appropriate for many communities. MSD should generally consider them to be low
priority BMPs.
• Between 0.4 and 0.6 – Moderate implementation. The BMP is commonly used and
should be considered for MSD’s program, if applicable.
• Greater than 0.6 – High implementation. The BMP is commonly used in most
communities. MSD should generally consider these to be high priority BMPs and identify
opportunities to include within the stormwater program.
Results of the evaluation show that the implementation of non-structural bacteria and nutrient
BMPs varies between MCMs and across the surveyed communities (Figure 2). In general, BMPs
under MCMs #1 (public education and outreach) and #6 (pollution prevention and good
housekeeping) have limited implementation, with several BMPs scoring between 0 and 0.4 for
all of the communities. The primary exceptions to this limited implementation are pet waste and
fertilizer outreach programs under MCM #1. In contrast, many BMPs under MCMs #3 (illicit
discharge detection and elimination) and #5 (post-construction stormwater management) have
scores between 0.6 and 1, indicating that these BMPs are generally implemented actively by all
of the communities. Results from MCM #2 (public involvement and participation) suggest that
most BMPs are consistently but moderately implemented by the communities (scores of 0.4 to
0.6).
The community survey scores were compared to those from MSD’s program to evaluate the
District’s current progress relative to other established programs and identify potential areas for
future enhancement. An overview of results for MSD’s stormwater program relative to the
surveyed communities for each MCM is included below. An overview of results for MSD’s
program relative to the surveyed communities for each MCM is included below.
• MCM #1 – Public Education and Outreach: Most BMPs are implemented to a limited
degree (score of less than 0.4) across the surveyed communities. Similarly, MSD does not
use many of the BMPs that were reviewed. With the exception of fertilizer outreach
efforts, BMPs that MSD does apply are implemented more actively relative to the other
MS4s.
• MCM #2 – Public Involvement and Participation: With the exception of downspout
disconnection and site designs (BMP 2.7), BMPs under this MCM are at least moderately
implemented across the communities. MSD implements most of the BMPs to a
comparable or greater degree than the other communities.
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• MCM #3 – Illicit Discharge Detection and Elimination: In general, these BMPs are
highly implemented across the communities. MSD implements a majority of BMPs under
this MCM to a comparable or greater degree than the other communities.
• MCM #4 – Construction Site Stormwater Runoff Control: MSD’s implementation of
the two BMPs reviewed under this MCM are generally comparable to the other
communities.
• MCM #5 – Post-Construction Stormwater Management: BMPs under this MCM are
actively implemented across the communities. MSD implements a majority of BMPs to a
comparable or greater degree than the other communities.
• MCM #6 – Pollution Prevention and Good Housekeeping: Implementation of BMPs
under this MCM was mixed across the surveyed communities. The BMPs that MSD does
apply are generally implemented more actively relative to the other communities.
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Figure 2. Summary of Non-Structural Bacteria and Nutrient BMP MS4 Community Survey Results. Normalized
implementation scores were calculated based on the degree to which each BMP is implemented across the
surveyed communities. For a given result, values near 0 indicate that few communities use the BMP with limited
implementation; values near 1 indicate that most communities use the BMP with extensive implementation. For
BMP identification numbers, refer to the community survey results in Table A-5.
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As MSD investigates enhancements to their stormwater programs over time, program managers
should initially focus on evaluating high priority (scores greater than 0.6) BMPs from the
community survey that are either not widely used or currently have limited implementation in the
St. Louis area. These include a using a public reporting tool (BMP 3.6), improving existing
septic system inventory activities (BMP 3.8), and increasing street sweeping frequency (BMP
6.8).
Once high priority BMPs have been addressed, MSD should review the moderately-implemented
(scores of 0.4 – 0.6) community survey BMPs to determine if they can be used or improved.
These BMPs include:
• Conducting private fertilizer education programs (BMP 1.3),
• Creating a tree sale program (BMP 2.2),
• Increasing the number and accessibility of public trash cans and pet waste stations (BMP
2.6),
• Improving baseflow source identification practices (BMP 3.1),
• Conducting instream algae monitoring (BMP 3.10),
• Improving construction site runoff control procedures on small sites (BMP 4.2), and
• Establishing a septic system elimination program (BMP 3.9).
MSD has recently worked to eliminate some septic systems in the St. Louis City and County area
as part of their Sewer Connection and Septic Tank Closure Program. Funding for this program
included a one-time allocation of approximately $2 million from MSD’s Project Clear. MSD and
their co-permittees should review the efficacy of the recent elimination program and determine
its viability as a permanent BMP going forward.
BMPs identified as having limited implementation in the community survey should be
considered a low priority for potential incorporation into MSD’s stormwater management
program. These BMPs should be reviewed over time as resources permit.
Other Considerations that Affect MEP for Non-Structural BMPs
While it is useful to understand MCM implementation by other MS4 communities across the
country to help establish what MEP is, MEP is also established in part by standard guidance. For
example, in ASCE’s Pathogens in Urban Stormwater Systems 12 report and presentations, it is
12 Urban Water Resources Research Council (UWRRC). 2014. Pathogens in Urban Stormwater Systems.
Environmental and Water Resources Institute. American Society of Civil Engineers.
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noted that non-structural BMP selection should be agency-specific (and thus not be designed to
precisely match the actions of other communities) and based on local sources. Local sources of
nutrients and bacteria should first be identified based on existing available GIS and monitoring
data, local knowledge and observations, and special studies. Then sources should be prioritized
based on risk level (e.g., human waste presents a greater illness risk than non-human and non-
fecal bacteria, certain forms of nutrients are more bioavailable or controlling in the
eutrophication process), and controllability. Once local sources are prioritized, then non-
structural source control BMPs should be selected to specifically target the highest priority
sources. This process, as documented through nationwide guidance, further helps to establish the
MEP.
An example process for bacteria is described here. Bacteria sources are typically ubiquitous in
the urban environment and numerous sources could contribute to excessive levels in urban
waterbodies. Therefore, a list of general urban sources and identification of non-structural BMPs
to address these typical sources would likely be too broad to develop a tailored non-structural
BMP program for each subwatershed or MS4 community. Guidance for identifying
subwatershed or MS4 community-specific bacteria sources can be found in the ASCE
publication, Pathogens in Urban Stormwater Systems, including:
• GIS mapping and analysis of infrastructure and analysis of monitoring data to identify
potential problem areas;
• Meeting with field staff and others with experience in the subwatershed to compile their
local knowledge;
• Subwatershed-specific observations;
• Enhanced illicit discharge detection and elimination (IDDE) investigations of MS4,
including microbial source tracking and traditional tools (e.g., CCTV and dye testing).
This source inventory could then be categorized and prioritized based on controllability and
public health risk, with human, non-human, and non-anthropogenic sources representing high,
medium, and low risk categories, respectively. Then non-structural BMPs could be selected to
effectively target the high and medium risk categories as comprehensively as possible and as
available funding allows. The ASCE pathogen publication provides examples of cost-effective
potential BMPs that may be considered based on the source identification findings, including:
• Sewer repairs where enhanced IDDE investigations have shown wastewater collection
systems leaking into the MS4
• Education/outreach to residential homeowners on limiting fertilizer application
• Improved prevention/housekeeping practices to limit fertilizer use by municipal
operations
• Pet waste disposal ordinances in areas of high pet density.
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Ultimately it may be more effective to aggressively implement a fewer number of BMPs that are
targeted to highest priority sources than to attempt to match the level of BMP implementation of
most other MS4 communities. For example, while resource intensive, septic inspection/inventory
and illicit connection detection are two of the most important BMPs for controlling human waste
and pathogens. MSD is implementing these BMPs at a “medium” or lower level. With increased
resources, efforts could be focused in high priority areas to better match the state of the practice
as documented in available nationwide guidance.
SUMMARY AND NEXT STEPS
Several new state regulatory requirements will impact how MSD administers their stormwater
management program. These new requirements will require MSD to evaluate and identify BMPs
that reduce bacteria and nutrients in stormwater runoff to the MEP. To assist MSD in
characterizing MEP for bacteria and nutrient, MSD’s existing structural and non-structural BMPs
were evaluated relative to the state of the practice and other MS4 programs. Significant findings
from this evaluation include the following:
• The top ranked structural BMPs (with a combined cost and benefit score above 4, as
shown in Table 7) were those that reduce runoff volume through infiltration or capture or
had advanced flow through designs. Few flow-through structural BMPs have effluent
concentrations that consistently meet water quality criteria for bacteria and nutrients
(only ponds).
• Approximately 70% of the built or planned structural BMPs in the MSD MS4 area are
ranked in the top three for benefits and have average scores (approximately 2) for costs.
• Post-construction ordinances and very basic structural BMPs were top ranked based on
costs, however these BMPs provided only minimal benefits.
• The treatment structural BMPs that incorporate advanced design characteristics (e.g.,
subsurface flow wetlands and enhanced biofilters) provide top ranked benefits, however,
their poor costs rankings can be prohibitive for some implementation scenarios.
• Site-specific feasibility issues and constraints can dramatically affect the performance
and costs of BMP types and should be considered early in the planning process.
• Going forward, MSD should focus on evaluating high priority (scores of greater than 0.6)
BMPs from the community survey that are either not widely used or currently have
limited implementation in the St. Louis area. Once high priority BMPs have been
addressed, MSD should review the moderately-implemented (scores between 0.4 and 0.6)
community survey BMPs to determine if they can be used or improved. Community
survey BMPs with limited implementation (scores less than 0.4) should be reviewed as
resources become available.
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• A comprehensive source identification and prioritization process directing the
implementation of non-structural BMPs can dramatically affect the effectiveness and
efficiency of the program.
Table 7 Benefits and Estimates of Probable Capital and Maintenance Costs
BMP
Estimated Benefits
Score
(Out of 3)
Estimated Cost
Score
(Out of 3)
Infiltration BMPs 2.9 2.4
Subsurface Flow Wetlands 2.8 NA
Ponds 2.6 2.3
Enhanced Biofilters 2.5 NA
Bioretention 2.4 2.4
Permeable Pavement 2.0 2.2
Surface Sand Filters 1.8 1.6
Underground Sand Filters 1.8 1
Underground Manufactured Filters 1.5 1.6
HDS Units 1.5 1.4
Cisterns 1.4 2.5
Impervious Area Reduction 1.4 NA
Engineered Swales 1.3 3.0
Stream Buffer 1.2 NA
Tree Preservation Ordinance 1.2 NA
Not applicable (NA) was assigned to BMPs that did not have available cost information.
Results of this evaluation can be used to help review the MSD BMP Toolbox
(http://www.stlmsd.com/what-we-do/stormwater-management/bmp-toolbox) and identify
potential areas to enhance BMP implementation. Some preliminary examples include:
• Highlighting the importance of implementing BMPs that focus on bacteria and nutrient
reduction.
• Providing guidance for the selection of BMPs capable of achieving bacteria and nutrient
reduction given site-specific conditions (e.g., land use, space constraints, rainfall patterns,
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etc.) or identified sources (e.g., residential and municipal over-fertilization, dumpsters,
washdown and grease traps at food outlets).
• Providing additional BMP design guidance related specifically to bacteria and nutrient
removal including:
o Vegetation selection
o Outlet controls/contact time guidance
o Media selection and specification
o Removal of compost/alternative soil amendments (a source of nutrients)
o Incorporation of saturated zone for bacteria and/or nitrogen removal
o Incorporation of an activated alumina layer for phosphorus removal
o Other pertinent design information based on findings from literature
* * * * *
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ATTACHMENT A
BMP EVALUATION RESULTS
MSD Structural BMP Evaluation
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Table A-1. Benefit Scores for Each Structural Best Management Practice (BMP)/Target Pollutant Combination
E. Coli Treatment Nitrite (NO2) + Nitrate (NO3) as
Nitrogen Treatmentd Total Phosphorus Treatment
Post-Construction Structural
BMPs BMP Database Category
Median Effluent
Concentration
(colonies /100ml)
Statistically
Significant
Removal (Y/N)
Score
Median
Effluent
Concentration
Statistically
Significant
Removal
(Y/N)
Score
Median
Effluent
Concentration
Statistically
Significant
Removal
(Y/N)
Score
(mg/L) (mg/L)
Bioretention Bioretention 101 Y 3 0.37 N 1 0.24 N 1
Infiltration BMPs Not Available Not Available 3 Not Available 3 Not Available 3
Engineered Swales Biofilter - Grass Swale 4,182 N 1 0.22 N 1 0.171 N 1
Permeable Pavement Porous Pavement Not Available 3 1.35 N 3 0.1 Y 3
Cisterns Not Available Not Available 1 Not Available 1 Not Available 1
Ponds Retention Pond 100 Y 3 0.13 Y 2 0.091 Y 2
Surface Sand Filters Media Filter 420a Y 2 0.57 N 1 0.089 Y 2
Underground Sand Filters Media Filter 420a Y 2 0.57 N 1 0.089 Y 2
Underground Manufactured
Filters Manufactured Device - Filtration 910b N 1 0.29c N 1 0.06 Y 2
HDS Units Manufactured Device - Physical 910b N 1 0.36c Y 2 0.22 Y 2
a. The International Stormwater BMP Database does not have sufficient data for Media Filter E. coli effluent concentrations; therefore, the reported fecal coliform was evaluated.
b. The BMP Database does not have sufficient data for Manufactured Devices (Filtration and Physical) E. coli effluent concentrations; therefore, the reported fecal coliform was evaluated.
c. The BMP Database does not have sufficient data for Manufactured Devices (Filtration and Physical) NO2 + NO3 as Nitrogen effluent concentrations; therefore, NOx as Nitrogen was evaluated.
d. NO2 + NO3 as Nitrogen was evaluated since it had the most results in the BMP Database.
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Table A-2. Additional Benefit Scores for Each BMP/Targeted Benefit Combination
Other Water Quality Treatment Flood Management Habitat / Environmental Community Enhancements
Post-Construction Structural BMPs Sediment
Reduction
Metals
Reduction Score Volume
Reductiona
Peak Flow
Reduction Score Habitat
Creation Score
Enhancement/
Creation of Public
Use Areas
Educational
Opportunities
Community
Aesthetics Score
Bioretention High High 3.0 High Medium 2.5 High 3.0 High High High 3.0
Infiltration BMPs High High 3.0 High High 3.0 Medium 2.0 Medium High Medium 2.3
Engineered Swales Medium Medium 2.0 Low Low 1.0 Medium 2.0 Medium Medium Medium 2.0
Permeable Pavement Medium Medium 2.0 Medium Medium 2.0 Low 1.0 Low Medium Low 1.3
Cisterns High Medium 2.5 High Medium 2.5 Low 1.0 Low Medium Medium 1.7
Ponds High High 3.0 Low High 2.0 High 3.0 High High High 3.0
Surface Sand Filters High High 3.0 Low Low 1.0 Low 1.0 Low Medium Low 1.3
Underground Sand Filters High High 3.0 Low Low 1.0 Low 1.0 Low Low Low 1.0
Underground Manufactured Filters High High 3.0 Low Low 1.0 Low 1.0 Low Low Low 1.0
HDS Units Medium Medium 2.0 Low Low 1.0 Low 1.0 Low Low Low 1.0
Post-Construction Ordinances
Stream Buffer Medium Medium 2.0 Low Medium 1.5 High 3.0 High Medium High 2.7
Tree Preservation Ordinance Low Low 1.0 Medium Low 1.5 High 3.0 High Medium High 2.7
Impervious Area Reduction Medium Medium 2.0 Medium Medium 2.0 Medium 2.0 High Low Medium 2.0
Advanced Structural BMPs
Enhanced Biofilters (e.g., Bioretention
with underdrains) High High 3.0 Medium Medium 2.0 High 3.0 Medium High High 2.7
Subsurface Flow Wetlands High High 3.0 Medium Medium 2.0 High 3.0 High High High 3.0
a. It is assumed that all the BMPs are sized to treat the same design storm (e.g., bypass from a flow through BMP such as engineered swales, sand filter, pond, etc. would be as frequent as from a retention BMP such as bioretention, infiltration
basin, etc.). For this reason, both bioretention and cisterns are assumed to have high volume reduction.
MSD Structural BMP Evaluation
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Table A-3. Summary of Structural BMP/Benefit Scoring
Target Pollutant Benefitsa Additional Benefits
E. Coli
Total
Nitrogen
Total
Phosphorus
Other
Water
Quality
Flood
Management
Habitat/
Environmental
Community
Enhancements Total Score Rank
(out of 15)
Weighting 30% 15% 15% 15% 10% 7% 8% 100%
Post-Construction Structural
BMPsb
% of BMPs Built
or Planned 1-3 1-3 1-3 1-3 1-3 1-3 1-3 3
Bioretention 48% 3.0 1.0 1.0 3.0 2.5 3.0 3.0 2.4 5
Infiltration BMPs 1% 3.0 3.0 3.0 3.0 3.0 2.0 2.3 2.9 1
Engineered Swales 4% 1.0 1.0 1.0 2.0 1.0 2.0 2.0 1.3 13
Permeable Pavement 18% 3.0 1.0 2.0 2.0 2.0 1.0 1.3 2.0 6
Cisterns 1% 1.0 1.0 1.0 2.5 2.5 1.0 1.7 1.4 11
Ponds 1% 3.0 2.0 2.0 3.0 2.0 3.0 3.0 2.6 3
Surface Sand Filters 4% 2.0 1.0 2.0 3.0 1.0 1.0 1.3 1.8 7
Underground Sand Filters 1% 2.0 1.0 2.0 3.0 1.0 1.0 1.0 1.8 8
Underground Manufactured Filters 1% 1.0 1.0 2.0 3.0 1.0 1.0 1.0 1.5 9
HDS Units 6% 1.0 2.0 2.0 2.0 1.0 1.0 1.0 1.5 9
Total systems install on new or
redevelopment since 2006 4,516
Post-Construction Ordinances
Stream Buffer NA 1.0 1.0 1.0 2.0 1.0 3.0 3.0 1.2 15
Tree Preservation Ordinance NA 1.0 1.0 1.0 1.0 1.0 3.0 2.0 1.2 14
Impervious Area Reduction NA 1.0 1.0 1.0 2.0 2.0 2.0 2.0 1.4 12
Advanced Structural BMPs
Enhanced Biofilters NA 3.0 1.0 3.0 3.0 1.0 3.0 3.0 2.5 4
Subsurface Flow Wetlands NA 3.0 3.0 3.0 3.0 1.0 3.0 3.0 2.8 2
a. BMPs with high volume reduction (see the Flood Management category in Table A-2) have a target pollutant benefit of 5. For BMPs with medium volume reduction have 1 point added to each
target pollutant effluent concentration score
b. The permitted structural BMP "storm credits" and "other" are not included in the BMP scoring because of the variety of approaches used in each of those categories
MSD Structural BMP Evaluation
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Table A-4. Summary of Structural BMP/Cost Scoring
Initial Capital Cost Estimate Rangea Annual Maintenance Cost Estimate Range Averaged
Score
(out of 3)
Rank
(out of 10) (Treatment for a 1-acre site) (Per System)
Post-Construction Structural
Controls Low High Average Low High Average
Bioretention $7,800 $25,400 $16,600 $4,000 $2,450 $19,050 2.4 3
Infiltration BMPs $4,800 $29,000 $16,900 $4,400 $2,550 $19,450 2.4 4
Engineered Swales $3,500 $18,700 $11,100 $1,300 $750 $11,850 3.0 1
Permeable Pavement $8,200 $27,600 $17,900 $3,100 $1,950 $19,850 2.3 5
Cisterns $12,400 $21,600 $17,000 $800 $500 $17,500 2.5 2
Ponds $9,000 $26,900 $17,950 $4,500 $2,600 $20,550 2.3 6
Surface Sand Filters $14,400 $38,800 $26,600 $3,200 $2,050 $28,650 1.6 8
Underground Sand Filters $16,200 $50,200 $33,200 $3,700 $2,350 $35,550 1.0 10
Underground Manufactured
Filters $12,200 $39,300 $25,750 $4,600 $2,850 $28,600 1.6 7
HDS Units $14,100 $42,200 $28,150 $3,700 $2,350 $30,500 1.4 9
Post-Construction Ordinancesb
Stream Buffer NA NA
Tree Preservation Ordinance NA NA
Impervious Area Reduction NA NA
Advanced Structural Controlsb
Enhanced Biofilters NA NA
Subsurface Flow Wetlands NA NA
a. Cost curves are not on a per acre basis as many costs are necessary for the first unit of BMP. Subsequent/additional costs may not be linear and may not have a one to one
relationship with area. Approximate volume of treatment for the 1-acre site was about 1450-2700 ft3. Sizing for cost estimation does not include achieving a required level
of performance.
b. Cost estimates were not available for post-construction ordinances or advanced structural BMPs, therefore relative costs were assigned using best professional judgment.
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Table A-5. Non-Structural Bacteria and Nutrient Best Management Practice (BMP) MS4 Community Survey Results.