This chapter shall be known and cited as the "Wissahickon Creek
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 groundwater recharge, 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 streambeds and stream
banks, thereby increasing sedimentation), destroying aquatic habitat,
and increasing 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 is an important resource which provides groundwater recharge
for water supplies and baseflow of streams, which also helps to protect
and maintain 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, groundwater recharge, stream baseflow, and aquatic
ecosystems.
F.
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).
G.
Nonstormwater discharges to municipal separate storm sewer systems
can contribute to pollution of waters of the commonwealth.
The purpose of this chapter is to promote the public health, safety and welfare within the Wissahickon Creek Watershed by maintaining the natural hydrologic regime and by minimizing the harms and maximizing the benefits described in § 163-2 of this chapter through provisions designed to:
A.
Meet legal water quality requirements under state law, including
regulations at 25 Pa. Code Chapter 93, to protect, maintain, reclaim
and restore the existing and designated uses of the waters of the
commonwealth.
B.
Preserve the natural drainage systems as much as possible.
C.
Manage stormwater close to the source.
D.
Provide procedures and performance standards for stormwater planning
and management.
E.
Maintain groundwater recharge to prevent degradation of surface water
and groundwater quality and to otherwise protect water resources.
F.
Prevent scour and erosion of stream banks and streambeds.
G.
Provide proper operation and maintenance of all stormwater best management
practices (BMPs) that are implemented within the municipality.
H.
Provide standards to meet National Pollutant Discharge Elimination
System (NPDES) requirements.
I.
Meet legal water quality requirements under state law, including
regulations at 25 Pa. Code § 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.
J.
Address the quality and quantity of stormwater discharges.
K.
Provide standards necessary to meet NPDES permit requirements.
L.
Implement an illegal discharge detection and elimination program
that addresses nonstormwater discharges into the municipality's
separate storm sewer system.
M.
Preserve and restore the flood-carrying capacity of streams.
N.
Prevent scour and erosion of stream banks and streambeds.
O.
Provide proper operation and maintenance of all stormwater management
facilities and BMPs that are implemented in the municipality.
The municipality is empowered to regulate land use and activities
that may affect runoff and surface water and groundwater quality and
quantity by the authority of:
A.
Primary authority. The municipality is empowered to regulate land
use activities that affect runoff and surface water and groundwater
quality and quantity by the authority of the Act of October 4, 1978,
P.L. 864 (Act 167), 32 P.S. § 680.1 et seq., as amended,
the Storm Water Management Act.
A.
All regulated activities and all activities that may affect stormwater runoff, including land development and earth disturbance activities, within those portions of the Wissahickon Creek Watershed located within the Township are subject to regulation by this chapter. This chapter shall apply to those portions of the municipality that lie within the Wissahickon Creek Watershed, in accordance with the stormwater management districts established in § 163-26.
B.
Regulated activities include the following:
(1)
Land development.
(2)
Subdivisions.
(3)
Alteration of the natural hydrologic regime.
(4)
Construction or reconstruction (see definition in § 163-13) of or addition of new impervious or semipervious surfaces (i.e., driveways, parking lots, roads, etc.).
(5)
Construction of new buildings or additions to existing buildings.
(6)
Redevelopment.
(7)
Diversion piping or encroachments in any natural or man-made channel.
(8)
Stormwater BMPs or appurtenances thereto.
(9)
Earth disturbance activities equal to or greater than 5,000 square
feet.
(10)
Any of the above regulated activities which were approved more
than five years prior to the effective date of this chapter and resubmitted
for municipal approval.
A.
Table 163-6 summarizes the exemptions from certain requirements in this chapter. "Proposed impervious surface" in Table 163-6 includes new, additional or replacement impervious surface/cover. Repaving existing surfaces without reconstruction (see § 163-13) does not constitute replacement.
|
Table 163-6
Exemptions
| ||||||||
|---|---|---|---|---|---|---|---|---|
|
Article or Section
|
Type of Project
|
Proposed New Impervious Cover
| ||||||
|
<1,000 square feet
|
>1,000 to <5,000 square
feet
|
>5,000 square feet
| ||||||
|
Earth Disturb-ance <5,000 square feet
|
Earth Disturb-ance >5,000
square feet to 1 acre*
|
Earth Disturb-ance >1 acre
|
Earth Disturb-ance <5,000 square feet*
|
Earth Disturb-ance >5,000
square feet to 1 acre*
|
Earth Disturb-ance >1 acre
|
All Earth Disturb-ance Categories
| ||
|
Article III, SWM site plan requirements
|
Development and re-development
|
Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
|
§ 163-22, non-structural project design
|
Development and re-development
|
Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
|
§ 163-23, groundwater recharge
|
Development and re-development
|
Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
|
§ 163-24, water volume control requirements
|
Development and re-development
|
Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
|
§ 163-25, stream bank erosion requirements
|
Development
|
Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
|
Re-development
|
Exempt
|
Exempt
|
Exempt
|
Not Exempt
|
Not Exempt
| |||
|
§ 163-26, stormwater peak rate controls and management districts
|
Development and re-development
|
Exempt
|
Exempt
|
Not Exempt
|
Exempt
|
Exempt
|
Not Exempt
|
Not Exempt
|
|
Erosion and sediment pollution control plan
|
Earth disturbance
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
Not Exempt
|
|
Not Exempt
| ||||||||
|
NOTES:
| |
|---|---|
|
Exempt = Exempt unless a determination is made by the municipality that the project is subject to § 163-6C.
| |
|
Not exempt = Not exempt. All provisions apply.
| |
|
*
|
Not exempt, but the municipality has adopted the ordinance for the Small Project SWM Site Plan for Residential Development in Appendix B (included as an attachment to this chapter); therefore, a small project SWM site plan may be submitted in lieu of the SWM site plan for residential development.
|
B.
Exemptions for land use activities. (NOTE: Appendix B contains guidance
for preparation of small project SWM site plans.[1] This guidance provides property owners who propose such
small regulated activities the opportunity to submit SWM site plans
without having to hire qualified persons.)
(1)
Disconnected regulated activities (regulated activities that create disconnected impervious areas) smaller in area than 1,000 square feet are exempt from the SWM site plan (§ 163-14) preparation requirements of this chapter, except when the associated earth disturbance area is equal to or greater than 5,000 square feet.
(2)
Disconnected regulated activities (regulated activities that create disconnected impervious areas), having an area equal to or greater than 1,000 square feet and less than 5,000 square feet, and with an associated earth disturbance area of less than 5,000 square feet, are exempt only from the peak rate control (§ 163-26) requirements of this chapter in the case of new development, and are exempt from peak rate control (§ 163-26) and stream bank erosion (§ 163-25) requirements in the case of redevelopment.
(3)
Agricultural plowing and tilling are exempt from the rate control
and SWM site plan preparation requirements of this chapter, provided
the activities are performed according to the requirements of 25 Pa.
Code Chapter 102.
(4)
Forest management and timber operations are exempt from the rate
control and SWM site plan preparation requirements of this chapter,
provided the activities are performed according to the requirements
of 25 Pa. Code Chapter 102.
[1]
Editor's Note: Appendix B is included as an attachment to this chapter.
C.
Infiltration exemptions.
(1)
Depth to limiting zone. A minimum of two feet of soil suitable for
infiltration must exist between the invert of the infiltration BMP
and the top of the nearest limiting zone. Otherwise, the Rev requirement shall not be applied to the development
site, and the entire WQv must be treated.
(2)
Hotspots.
(a)
Stormwater hotspots. Below is a list of types of hotspots that
may be recognized by the municipality. If a site is a potential hotspot,
it has important implications for how stormwater is managed. First
and foremost, untreated stormwater runoff from hotspots concentrated
into a collection system shall not be recharged into groundwater where
it may contaminate water supplies. Therefore, the Rev requirement shall not be applied to development sites that lie within
a hotspot (the entire WQv must still be treated).
Second, a greater level of stormwater treatment shall be applied at
hotspot sites to prevent pollutant washoff after construction. The
Environmental Protection Agency's (EPA) National Pollutant Discharge
Elimination System (NPDES) stormwater program requires some industrial
sites to prepare and implement a stormwater pollution prevention plan.
(b)
List of potential hotspots:
[1]
Vehicle salvage yards and recycling facilities.
[2]
Vehicle fueling stations.
[3]
Vehicle service and maintenance facilities.
[4]
Vehicle and equipment cleaning facilities.
[5]
Fleet storage areas (bus, truck, etc.).
[6]
Industrial sites, based on Standard Industrial Codes.
[7]
Marinas (service and maintenance).
[8]
Outdoor liquid container storage.
[9]
Commercial/industrial facilities.
[10]
Public works storage areas.
[11]
Facilities that generate, transfer, store or dispose of hazardous
materials.
[12]
Commercial container nursery.
(c)
The following land uses and activities are not normally considered
hotspots:
(3)
Rate of infiltration: When infiltration is not feasible due to poor
infiltration rates or hotspots, the water quality volume must be treated
by an approved SMP.
D.
Additional exemption criteria:
(1)
Exemption responsibilities. An exemption shall not relieve the applicant
from implementing such measures as are necessary to protect public
health, safety, property, water quality and the environment.
(2)
Drainage problems. Where drainage problems exist downstream of the
proposed activity, then the municipality may deny exemptions.
(3)
Exemptions are limited to specific portions of this chapter.
(4)
HQ and EV streams. The municipality shall deny exemptions in high
quality (HQ) or exceptional value (EV) waters and source water protection
areas (SWPA).
(5)
For a development taking place in stages, the entire development
plan must be used in determining compliance with these exemption criteria.
The starting point from which to consider tracts as "parent tracts"
in which future subdivisions and respective impervious area computations
are cumulatively considered shall be the date of the municipal ordinance
adoption of the original Wissahickon Creek Watershed Stormwater Management
Plan Ordinance (Ord. No. 2014-11, adopted October 27, 2014). For example:
If a property owner proposes a three-hundred-square-foot shed after
adoption of the municipal Stormwater Management Ordinance, that property
owner would be exempt from site plan and peak rate control requirements.
If, at a later date, the property owner proposes to construct a garage
and driveway adding an additional 1,300 square feet of impervious
surface, the applicant would be required to submit an SWM site plan
or small project SWM site plan demonstrating the stormwater control
requirements for the total impervious surface of 1,600 square feet.
E.
The municipality may deny or revoke any exemption pursuant to this
section at any time for any project that the municipality believes
may pose a threat to public health, safety, property or the environment.
Any other ordinances, provisions or regulations of the municipality inconsistent with any of the provisions of this chapter are hereby repealed to the extent of the inconsistencies only. Municipalities with land area in more than one watershed may enact a single ordinance, provided that its provisions are at least as restrictive as the provisions herein. The specific peak rate controls and management districts in § 163-26 shall be included in the ordinance.
In the event that a court of competent jurisdiction declares
any section or provision of this chapter invalid, such decision shall
not affect the validity of any of the remaining provisions of this
chapter.
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, including 25 Pa. Code Chapters 92a, 102 and 105.
Notwithstanding any provision(s) of this chapter, including
exemptions, any landowner or any person engaged in the alteration
or development of land that may affect stormwater runoff characteristics
shall implement such measures as are reasonably necessary to prevent
injury to health, safety or other property. Such measures also shall
include actions as are required to manage the rate, volume, direction
and quality of resulting stormwater runoff in a manner that otherwise
adequately protects health, safety, property and water quality.
Any permit or authorization issued or approved based on false,
misleading or erroneous information provided by an applicant is void
without the necessity of any proceedings for revocation. Any work
undertaken or use established pursuant to such permit or other authorization
is unlawful. No action may be taken by a board, agency or employee
of the municipality purporting to validate such a violation.
