Chapter 2 - Proposed
Stormwater Quality Management Plan
2.0
Purpose
The
purpose of a Stormwater Quality Management Plan (SWQMP)
in Phase II of the U.S. Environmental Protection
Agency's (EPA) stormwater program originates from
the 1990 Clean Water Act (CWA) which aims to
preserve, protect, and improve the nation's water
resources from polluted stormwater run-off. A SWQMP
requires the institution of controls on the
unregulated sources of stormwater discharges,
otherwise referred to as non-point source pollutants
that have proven to be the greatest cause to the
impairment of our nation's water resources.
2.1 Governing Authority
The
Logansport Stormwater Management Board will continue
to serve as the managers and overall governing
authority of the City of Logansport's Stormwater
Quality Management Plan. In addition to the Board,
the Logansport Municipal Utility Departments, the
Logansport / Cass County Plan Commission, and the
City's Street Department will also be included as
major stakeholders in the development,
implementation, and maintenance of the proposed
Stormwater Quality Management Plan that follows.
2.2 Minimum Control Measures and their Measurable
Goals
The following Stormwater Quality Management Plan (SWQMP)
includes six minimum control measures (MCMs): (1)
public education and outreach; (2) public
participation and involvement; (3) illicit discharge
detection and elimination; (4) construction site
stormwater run-off control (which is also referred
to as erosion control); (5) post-construction
run-off control; and (6) pollution prevention and
good housekeeping. These minimum control measures
aim to preserve, protect, and improve Logansport's
water resources with respect to polluted stormwater
run-off.
Providing outreach and educating the public helps to
ensure greater support by the public and greater
compliance with the SWQMP itself. The public
education and outreach program, outlined in Chapter
3, aims to increase the number of persons residing
within the corporate limits of Logansport that are
educated about stormwater quality by 5%. The goal
is to achieve the 5% increase by the end of the
5-year permit term.
An
active and involved community is crucial to the
success of a stormwater management program because
it allows for: broader public support by giving
citizens partial responsibility of the program;
shorter implementation schedules; a broader base of
expertise and economic benefits; and a lead into
other programs. The public participation and
involvement program, outlined in Chapter 4, aims to
increase the number of persons residing within the
corporate limits of Logansport that participate in
stormwater quality programs by 5%. The goal is to
achieve the 5% increase by the end of the 5-year
permit term.
Recognizing the adverse effects illicit discharges
can have on receiving waters, Chapter 5 allows the
MS4 Operator to detect and eliminate illicit
discharges by gaining a thorough awareness of the
entire stormwater sewer system. The illicit
discharge detection and elimination program aims to
reduce the amount of stormwater pollution caused by
illicit discharges within the corporate limits of
Logansport by 10%. The goal is to achieve the 10%
reduction by the end of the 5-year permit term.
Construction site stormwater management in areas
undergoing new development or redevelopment is
necessary to keep polluted stormwater run-off from
entering the MS4 conveyances that discharge into the
City of Logansport receiving waters untreated. The
construction site run-off control program, outlined
in Chapter 6, aims to reduce the amount of total
suspended solids leaving individual construction
sites by 80%. The goal is to achieve the 80%
reduction during the construction period of any new
development required to gain local approval.
Similarly, post-construction stormwater management
in areas undergoing new development or redevelopment
is necessary to keep run-off from entering the MS4
conveyances that discharge into the City of
Logansport's receiving waters untreated. The
post-construction stormwater run-off control
program, outlined in Chapter 7, aims to reduce the
amount of total suspended solids leaving any new
site development or redevelopment after construction
by 80%. The goal is to achieve the 80% reduction
for all new site developments required to gain local
approval.
The pollution prevention and good housekeeping measure is meant to
improve or protect receiving water quality by
altering municipal facilities operations. The
pollution prevention and good housekeeping program,
outlined in Chapter 8, aims to reduce the amount of
stormwater pollution currently caused within
operational areas of Logansport by 10%. The goal is
to achieve the 10% reduction by the end of the
5-year permit term.
2.3 Narrative Summary of Structural BMPs Allowed
for New Development & Redevelopment
The following structural BMPs are proposed to be
allowed for new development and redevelopment. The
goal of these structural BMPs is to prevent 80% of
the total suspended solids (TSS) leaving any new
development or redevelopment construction site from
entering the City's conveyance system.
Stormwater Ponds:
Stormwater ponds are constructed stormwater
retention basins with a permanent pool (or micropool)
of water. Runoff from each rain event is captured
and treated in the pool. This includes wet ponds;
wet extended detention ponds; micropool extended
detention ponds; and multiple pond systems.
Detention Basins (Dry):
A dry detention basin is an area used to detain
stormwater for a relatively short period of time.
The area should be dry between storms. The basin
allows for particles and pollutants to settle out of
stormwater.
Catch Basins:
Catch basin inserts are small filtering devices
installed in each catch basin to trap suspended
solids and other pollutants. Catch basin inserts
are available in a variety of designs.
Stormwater Wetlands:
Stormwater wetlands are constructed, artificial
wetland systems used for stormwater management.
They consist of a combination of shallow marsh
areas, open water, and semi-wet areas above the
permanent pool. This includes shallow wetlands;
extended detention wetlands; pond/wetland systems;
and pocket wetlands.
Bioretention Areas:
Bioretention areas are shallow stormwater basins or
landscaped areas that utilize engineered soils and
vegetation to capture and treat stormwater run-off.
Sand Filters:
Sand filters are multi-chamber structures designed
to treat stormwater run-off through filtration using
a sand bed as its primary filter media. This
includes surface sand filters and perimeter sand
filters.
Water Quality Swales:
Water quality swales are vegetated open channels
that are designed and constructed to capture and
treat stormwater run-off within dry cells. This
includes dry swales.
Biofilters:
Biofilters provide some filtering capabilities,
however, they cannot meet the 80% TSS reduction goal
and must, therefore, be used only as pretreatment
measures or as part of a treatment train. This
includes filter strips and grass channels.
2.4 Narrative Summary of Structural BMP Selection
Criteria
The following selection criteria for structural BMPs
are allowed for new development and redevelopment.
Again, the goal of these structural BMPs is to
prevent 80% of the total suspended solids (TSS)
leaving any new development or redevelopment
construction site from entering the City's
conveyance system.
Development of Open Land:
The following BMPs are appropriate when developing
individual lots of open land for commercial strips,
light industry, and institutions: bioretention; wet
ponds; detention basins; artificial wetlands; sand
filters; water quality swales; catch basins; and
biofilters. Again, biofilters may only be used in
combination with other appropriate BMPs in order to
obtain a percentage reduction goal of 80%.
The following BMPs are appropriate when developing
open land for commercial or industrial subdivisions:
wet ponds; detention basins; and wetlands.
The following BMPs are appropriate when developing
open land for residential properties: bioretention;
wet ponds; detention basins; artificial wetlands;
water quality swales; and biofilters.
Redevelopment of a Commercial Building or Strip with
Medium Imperviousness:
The following BMPs are appropriate when redeveloping
a commercial building or strip with medium
imperviousness into another commercial development
or strip: bioretention; sand filters; catch basins;
wet ponds; detention basins; and wetlands.
Redevelopment of a Commercial Building or Strip that
is Small or has High Imperviousness:
The following BMPs are appropriate when redeveloping
a commercial building or strip that is small or has
high imperviousness into another commercial
development or strip: bioretention; sand filters;
and catch basins.
Redevelopment of Transportation Infrastructure:
The following BMPs are appropriate when increasing
or expanding transportation infrastructure: water
quality swales; wet ponds; detention basins;
artificial wetlands; and catch basins.
Allowed BMPs, selection criteria for appropriate
BMPs, and performance standards for individual BMPs
are discussed in more detail in the City's
Development Standards Manual.
2.5 Schedule for On-going Receiving Water
Characterization
The characterization of Logansport's receiving
waters was inconclusive given that past testing
locations, monitoring parameters, monitoring
frequency, and monitoring protocol were
inconsistent. Therefore, the following is the
proposed monitoring program to establish a baseline
for the quality of the City's receiving streams.
Locations:
Locations of monitoring points were developed based
on land use information in relation to the receiving
stream locations. Monitoring points were developed
in a manner so that the data will cover significant
stretches of the receiving streams. The purpose of
the layout of the monitoring points is to first
collect data over a large area. Then, collected data
will be analyzed to further associate particular
land uses with stormwater pollution. Monitoring
points may be changed in the future to gain a better
understanding of more specific areas.
There is at least one monitoring point for each
receiving stream. If a receiving stream begins
within Logansport's corporate limits, the receiving
stream only has one monitoring point. If a receiving
stream begins outside of Logansport's corporate
limits, a monitoring point was established nearest a
point that the receiving stream enters Logansport's
corporate limits. A second monitoring point was
established for the same receiving stream at a point
where the receiving stream leaves the corporate
limits.
Proposed Monitoring Parameters
|
Parameter |
Unit |
Sample |
Oil and grease
|
mg/l |
grab |
|
CBOD5 (Carbonaceous biochemical oxygen demand) |
mg/l |
grab |
|
COD (Chemical oxygen demand) |
mg/l |
grab |
|
TSS (Total suspended solids) |
mg/l |
grab |
|
TKN (Total Kjeldahl nitrogen) |
mg/l |
grab |
|
Total phosphorous |
mg/l |
grab |
|
pH |
s.u. |
grab |
|
NH3 (Ammonia) |
mg/l |
grab |
|
Nitrate plus nitrite nitrogen
|
mg/l |
grab |
|
E.coli |
Colonies/100mL |
grab |
|
DO (Dissolved Oxygen) |
mg/l |
grab |
|
Total Cadmium |
mg/l |
grab |
|
Hardness - Calcium Carbonate |
mg/l |
grab |
|
Total Zinc |
mg/l |
grab |
|
Arsenic |
mg/l |
grab |
|
Total Copper |
mg/l |
grab |
|
Total Lead |
mg/l |
grab |
|
Total Mercury |
mg/l |
grab |
|
Total Nickel |
mg/l |
grab |
Frequency:
Monitoring will be conducted starting in May of 2005 and
will continue to be done on an annual basis each May for
the duration of the City's NPDES permit. Monitoring
will include one dry weather sample and one wet weather
sample for each of the four sampling locations.
Protocol:
All eight dry weather samples will be taken on the same
day. A dry weather sample should be taken after a
minimum of four days without rainfall. The eight wet
weather samples will be taken within 24 hours of the end
of the rain event.
2.6 Narrative Summary of the Current & Projected
Stormwater Budget
Current financing of stormwater projects originates from
Logansport's Stormwater Utility funds. Ultimately all
financing will be provided by anticipated funds from the
stormwater management user fee ($2.95 per month per
resident). The following is the projected stormwater
budget for the City of Logansport. Each fee includes
professional fees, municipal wages and benefits, as well
as reproduction costs.
1.
Public Education and Outreach: $10,000/year
2.
Public Participation and Involvement:
$10,000/year
3.
Illicit Discharge Detection and Elimination:
$15,000/year
4.
Construction Site Run-off Control (Erosion
Control): $12,000/year
5.
Post-Construction Run-off Control: $12,000/year
6.
Pollution Prevention and Good Housekeeping;
$20,000/year
7.
On-Going Water Quality Characterization:
$10,000/year
8.
Other: $30,000/year
Monies allocated to each of the above line items are
subject to change. Individual programs may require more
or less money, depending on their efficiency and/or
success throughout the 5-year permit term.
2.7 Timetable for Program Implementation
The
table on the following page identifies the milestones
fully implementing the requirements set forth in Rule
13. A copy of 327 IAC 15-13 is included in Appendix
C. Rule 327 IAC 15-5 (Rule 5) is referenced in Rule
13. A copy of Rule 5 is included in Appendix D.
In addition, there are 5-year implementation schedules
for each of the activities, programs, and controls
proposed in each of the minimum control measure
chapters, Chapters 3-8.
