This chapter shall be known as the "Marple Township Stormwater
Management Ordinance."
The governing body of the municipality finds that:
A.
Inadequate management of accelerated stormwater runoff resulting
from development throughout a watershed increases flood flows and
velocities, contributes to erosion and sedimentation, overtaxes the
carrying capacity of existing streams and storm sewers, greatly increases
the cost of public facilities to convey and manage stormwater, undermines
floodplain management and flood reduction efforts in upstream and
downstream communities, reduces infiltration, and threatens public
health and safety.
B.
Inadequate planning and management of stormwater runoff resulting
from land development throughout a watershed can also harm surface
water resources by changing the natural hydrologic patterns, accelerating
stream flows (which increase scour and erosion of stream beds and
stream banks, thereby elevating sedimentation), destroying aquatic
habitat, and elevating aquatic pollutant concentrations and loadings
such as sediments, nutrients, heavy metals, and pathogens. Groundwater
resources are also impacted through loss of recharge.
C.
A comprehensive program of stormwater management, including minimization
of impacts of development, redevelopment, and activities causing accelerated
erosion and loss of natural infiltration, is fundamental to the public
health, safety, welfare, and the protection of the people of the municipality
and all of the people of the commonwealth, their resources, and the
environment.
D.
Stormwater can be an important water resource by providing infiltration
for water supplies and base flow of streams, which also protects and
maintains surface water quality.
E.
Impacts from stormwater runoff can be minimized by using project
designs that maintain the natural hydrologic regime and sustain high
water quality, infiltration, stream base flow, and aquatic ecosystems.
The most cost-effective and environmentally advantageous way to manage
stormwater runoff is through nonstructural project design that minimizes
impervious surfaces and sprawl, avoids sensitive areas (i.e., stream
buffers, floodplains, steep slopes), and considers topography and
soils to maintain the natural hydrologic regime.
F.
Public education on the control of pollution from stormwater is an
essential component in successfully addressing stormwater.
G.
Federal and state regulations require certain municipalities to implement
a program of stormwater controls. These municipalities are required
to obtain a permit for stormwater discharges from their separate storm
sewer systems under the National Pollutant Discharge Elimination System
(NPDES).
H.
Nonstormwater discharges to municipal separate storm sewer systems
can contribute to pollution of waters of the commonwealth by the municipality.
The purpose of this chapter is to promote the public health, safety, and welfare within the municipality by maintaining the natural hydrologic regime and minimizing the impacts described in § 257-2 of this chapter through provisions designed to:
A.
Promote alternative project designs and layouts that minimize the
impacts on surface and groundwater.
B.
Promote nonstructural best management practices (BMPs).
C.
Minimize increases in runoff stormwater volume.
D.
Minimize impervious surfaces.
E.
Manage accelerated stormwater runoff and erosion and sedimentation
problems and stormwater runoff impacts at their source by regulating
activities that cause these problems.
F.
Provide review procedures and performance standards for stormwater
planning and management.
G.
Utilize and preserve existing natural drainage systems as much as
possible.
H.
Manage stormwater impacts close to the runoff source, requiring a
minimum of structures and relying on natural processes.
I.
Focus on infiltration of stormwater to maintain base flow, to prevent
degradation of surface and groundwater quality, and to otherwise protect
water resources.
J.
Protect base flows and quality of streams and watercourses, where
possible.
K.
Meet legal water quality requirements under state law, including
regulations at 25 Pennsylvania Code Chapter 93.4a requiring protection
and maintenance of "existing uses" and maintenance of the level of
water quality to support those uses in all streams, and the protection
and maintenance of water quality in "special protection" streams.
L.
Address the quality and quantity of stormwater discharges from the
development site.
M.
Provide standards to meet certain NPDES MS4 permit requirements.
N.
Implement an illicit discharge detection and elimination program
that addresses nonstormwater discharges into the municipality's
separate storm sewer system (MS4).
O.
Preserve the flood-carrying capacity of streams.
P.
Prevent accelerated scour, erosion and sedimentation of stream channels.
Q.
Provide performance standards and design criteria based on watershed-wide
stormwater management planning.
R.
Provide proper operation and maintenance of all permanent stormwater
management facilities and BMPs that are implemented within the municipality.
The municipality is empowered or required to regulate land use
activities that affect runoff and surface and groundwater quality
and quantity by the authority of:
A.
All regulated activities and all activities that may affect stormwater
runoff, including but not limited to land development, redevelopment,
and earth disturbance activity located within the municipality, are
subject to regulation by this chapter.
B.
Additionally, all properties within the Township, at all times, are subject to provisions of Article VIII, Prohibitions, of this chapter.
C.
This chapter contains the stormwater management performance standards
and design criteria that are necessary from a watershed-wide perspective.
Local stormwater management design criteria (e.g., inlet spacing,
inlet type, collection system design and details, outlet structure
design, etc.) shall continue to be regulated by the applicable municipal
ordinances and applicable state regulations.
An exemption shall not relieve the applicant from implementing
the requirements of this chapter or from implementing such measures
as are necessary to protect public health, safety, and property. An
exemption shall not relieve the applicant from complying with the
special requirements for watersheds draining to identified high quality
(HQ) or exceptional value (EV) waters or any other current or future
state or municipal water quality protection requirements. If a drainage
problem is documented or known to exist downstream of, or is expected
from the proposed activity, then the municipality may withdraw exemptions
listed in Table 257-6.1 and require the applicant to comply with all
requirements of this chapter. Even though the applicant is exempt,
he/she is not relieved from complying with other municipal ordinances
or regulations.
A.
General exemptions.
(1)
Table 257-6.1 summarizes the exemptions from certain provisions of
this chapter. Exemptions are for the items noted in Table 257-6.1
only, and shall not relieve the applicant from other applicable sections
of this chapter.
(2)
Any regulated activity that is exempt from some provisions of this
chapter is exempt only from those provisions. If development is to
take place in phases, the developer is responsible for implementing
the requirements of this chapter as the impervious cover/earth disturbance
threshold is met. The date of the adoption of this chapter shall be
the starting point from which to consider tracts as "parent tracts"
in which future subdivisions and respective impervious area and earth
disturbance computations shall be cumulatively considered. Exemption
shall not relieve the applicant from implementing such measures as
are necessary to protect health, safety, and property. For example:
|
If a property owner proposes a 150 square foot shed after adoption
of the this chapter, that property owner would be exempted from water
quality and quantity requirements of this chapter as noted in Table
257-6.1. If, at a later date, the property owner proposes to construct
a 499 square foot room addition, the applicant would be required to
comply with the requirements for the simplified method for the full
649 square feet of impervious cover created since adoption of this
chapter. If an additional 700 square foot swimming pool/patio is proposed
later, the property owner would be required to implement the full
stormwater quantity and quality control submission requirements of
this chapter for the total 1,349 square feet of additional impervious
surface added to the original property since adoption of this chapter.
|
|
Table 257-6.1
Exemptions
| |||||||
|---|---|---|---|---|---|---|---|
|
Article
or Section
|
Type of Project
|
Proposed Impervious Surface
|
Earth Disturbance
| ||||
|
0–499 square feet
|
500–999 square feet
|
1,000 + square feet
|
0–4,999 square feet disturbance
|
5,000 square feet –< 1 acre
|
> 1 acre
| ||
|
Article IV
SWM Site Plan Requirements
|
Development
Redevelopment
|
Exempt
|
Not exempt
Simplified approach
|
Not exempt
|
Exempt
|
Modified1
|
Not exempt
|
|
Section 257-13
Nonstructural project design
|
Development
Redevelopment
|
Exempt
|
Not exempt
Simplified approach
|
Not exempt
|
Exempt
|
Not exempt
|
Not exempt
|
|
Section 257-14
Infiltration volume
requirements
|
Development
Redevelopment
|
Exempt
|
Not exempt
Simplified approach
|
Not exempt
|
Exempt
|
Exempt
|
Not exempt
|
|
Section 257-15
Water quality requirements
|
Development
Redevelopment
|
Exempt
|
Not exempt
Simplified approach
|
Not exempt
|
Modified2
|
Modified2
|
Not exempt
|
|
Section 257-16
Stream bank erosion requirements
|
Development
Redevelopment
|
Exempt
|
Not exempt
Simplified approach
|
Not exempt
|
Exempt
|
Exempt
|
Not exempt
|
|
Section 257-17
Stormwater peak rate control and management districts
|
Development
Redevelopment
|
Exempt
|
Exempt
|
Not exempt
|
Exempt
|
Not exempt
|
Not exempt
|
|
Erosion and sediment pollution control requirements
|
Must comply with Title 25, Chapter 102 of the PA Code
and other applicable state and municipal codes, including the Clean
Streams Law.
|
Not exempt
| |||||
|
Legend:
| ||
|---|---|---|
|
•
|
"Proposed impervious surface" in Table 257-6.1 includes
new, additional, or replacement impervious surface/cover as part of
development or redevelopment.
| |
|
•
|
Exempt - Exempt from required section provision only;
SWM site plan submission may still be required if other section provisions
are applicable.
| |
|
•
|
Modified1 - Modified SWM site plan need only consist of items in § 257-21, Subsection A(2) and (4); Subsection B(7), (8), (11), and (22); and Subsection D(2) and (3) and related supportive material needed to determine compliance with §§ 257-13 and 257-17. Modified SWM site plan is required that includes all elements of § 257-13, as applicable.
| |
|
•
|
Modified2 - Modified SWM site plan need only consist of items and related material needed to determine compliance with § 257-15D.
| |
|
•
|
Simplified approach – Must comply with provisions
of Appendix B of this chapter.[1]
| |
|
•
|
Redevelopment – See § 257-17A for alternate stormwater peak rate control criteria.
| |
[1]
Editor's Note: Appendix B is on file in the Township offices..
B.
Exemptions for specific activities.
(1)
Use of land for gardening or home consumption.
(2)
Agriculture, when operated in accordance with a conservation plan,
nutrient management plan, or erosion and sedimentation control plan
approved by the County Conservation District, including activities
such as growing crops, rotating crops, tilling soil, and grazing animals.
For agriculture with an approved conservation plan, installation of
new or expansion of existing farmsteads, animal housing, waste storage,
and production areas having impervious surfaces that result in a net
increase in impervious surface of between 500 square feet and 999
square feet shall apply the simplified approach, and net increases
in impervious surface of greater than or equal to 1,000 square feet
shall be subject to the provisions of this chapter.
(3)
Forest management operations which are following the Department of Environmental Protection's (PADEP) management practices contained in its publication "Soil Erosion and Sedimentation Control Guidelines for Forestry," are operating under an approved erosion and sedimentation plan, and must comply with the stream buffer requirements in § 257-15D.
(4)
Repaving without reconstruction.
(5)
Emergency exemption. Emergency maintenance work performed for the
protection of public health, safety, and welfare. A written description
of the scope and extent of any emergency work performed shall be submitted
to the Marple Township Office of Code Enforcement within two calendar
days of the commencement of the activity. If the Marple Township Office
of Code Enforcement finds that the work is not an emergency, then
the work shall cease immediately, until a stormwater site plan in
accordance with this chapter is submitted and approved by the municipality.
(6)
Maintenance exemption. Any maintenance to an existing stormwater
management system made in accordance with plans and specifications
approved by the Municipal Engineer.
A.
Approvals issued pursuant to this chapter do not relieve the applicant
of the responsibility to secure required permits or approvals for
activities regulated by any other applicable code, rule, act, or ordinance.
B.
To the extent that this chapter imposes more rigorous or stringent
requirements for stormwater management, the specific requirements
contained in this chapter shall be followed.
C.
Nothing in this chapter shall be construed to affect any of the municipality's
requirements regarding stormwater matters that do not conflict with
the provisions of this chapter, such as local stormwater management
design criteria (e.g., inlet spacing, inlet type, collection system
design and details, outlet structure design, etc.). Conflicting provisions
in other municipal ordinances or regulations shall be construed to
retain. The requirements of this chapter shall supersede any conflicting
requirements in other municipal ordinance or regulations.
