The governing body of the municipality finds that:
A. 
Inadequate management of accelerated stormwater runoff resulting from development throughout a watershed increases runoff volumes, flood flows and velocities, contributes to erosion and sedimentation, degrades water quality, overtaxes the carrying capacity of 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, threatens public health and safety, and increases nonpoint source pollution of water resources.
B. 
A comprehensive program of stormwater management (SWM), including reasonable regulation of development and activities causing accelerated erosion, is fundamental to the public health, safety, welfare, and the protection of the people of the municipality and all the people of the commonwealth, their resources, and the environment.
C. 
Through project design, impacts from stormwater runoff can be minimized to maintain the natural hydrologic regime, and sustain high water quality, groundwater recharge, stream baseflow, and aquatic ecosystems. The most cost effective and environmentally advantageous way to manage stormwater runoff is through nonstructural project design, minimizing impervious surfaces and sprawl, avoiding sensitive areas (i.e., stream buffers, floodplains, steep slopes), and designing to topography and soils to maintain the natural hydrologic regime.
D. 
Inadequate planning and management of stormwater runoff resulting from land development and redevelopment 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 streambanks thereby elevating sedimentation), destroying aquatic habitat and elevating aquatic pollutant concentrations and loadings such as sediments, nutrients, heavy metals and pathogens.
E. 
The aforementioned impacts happen mainly through a decrease in natural infiltration of stormwater.
F. 
Stormwater is an important water resource by providing groundwater recharge for water supplies and base flow of streams, which also protects and maintains surface water quality.
G. 
Public education on the control of pollution from stormwater is an essential component in successfully addressing stormwater.
H. 
Federal and state regulations require certain municipalities to implement a program of stormwater controls. These municipalities are required to obtain a federal permit for stormwater discharges from their separate storm sewer systems under the National Pollutant Discharge Elimination System (NPDES) program.
I. 
Nonstormwater discharges to municipal separate storm sewer systems can contribute to pollution of waters of the commonwealth by the Township.
J. 
The use of green infrastructure and low-impact development (LID) are intended to address the root cause of water quality impairment by using systems and practices which use or mimic natural processes to: 1) infiltrate and recharge, 2) evapotranspire, and/or 3) harvest and use precipitation near where it falls to earth. Green infrastructure practices and LID contribute to the restoration or maintenance of predevelopment hydrology.
The purpose of this comprehensive stormwater management ordinance is to promote health, safety, and welfare within Hilltown Township and its watersheds by maintaining the natural hydrologic regime and by minimizing the harms and maximizing the benefits described in § 134-1 of this chapter through provisions designed to:
A. 
Meet water quality requirements under state law, including regulations at 25 Pa. Code Chapter 93.4a to protect, maintain, reclaim, and restore the existing and designated uses of the waters of this commonwealth; and maintain the level of water quality to support those uses in all streams, and to protect and maintain water quality in special protection streams.
B. 
Promote nonstructural best management practices.
C. 
Minimize increases in stormwater volume and control peak flow.
D. 
Minimize impervious surfaces.
E. 
Manage accelerated runoff and erosion and sedimentation problems at their source by regulating activities that cause these problems.
F. 
Utilize and preserve the existing natural drainage systems as much as possible.
G. 
Maintain the predevelopment volume of groundwater recharge and prevent degradation of groundwater quality.
H. 
Maintain the predevelopment peak and volume of stormwater runoff and prevent degradation of surface water quality.
I. 
Minimize nonpoint source pollutant loadings to the ground and surface waters.
J. 
Minimize impacts on stream temperatures.
K. 
Maintain existing flows and quality of streams and watercourses in the municipality and the commonwealth.
L. 
Preserve and restore the flood-carrying capacity of streams and natural drainage systems.
M. 
Provide for proper operations and maintenance of all permanent stormwater management facilities and best management practices that are implemented in the Township.
N. 
Provide performance standards and design criteria for watershed-wide stormwater management and planning.
O. 
Provide review procedures, performance standards, and design criteria for stormwater planning and management.
P. 
Manage stormwater runoff close to the source, reduce runoff volumes and mimic predevelopment hydrology by requiring a minimum of structures and relying on natural processes.
Q. 
Infiltrate stormwater to maintain groundwater recharge, to prevent degradation of surface and groundwater quality, and to otherwise protect water resources.
R. 
Prevent streambank and streambed scour and erosion.
S. 
Provide standards to meet National Pollution Discharge Elimination System (NPDES) permit requirements.
T. 
Address certain requirements of the Municipal Separate Stormwater Sewer System (MS4) NPDES Phase II Stormwater Regulations.
U. 
Implement an illegal discharge detection and elimination program to address nonstormwater discharges into the municipal separate storm sewer system.
The municipality is empowered to regulate land use activities that affect runoff 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; and by the authority of Pennsylvania Municipalities Planning Code, Act 247 of 1968, as amended by Act 170 of 1988, as further amended by Act 209 of 1990 and Act 131 of 1992, 53 P.S. § 10101.
A. 
This chapter shall apply to all areas of the municipality that are located within the Neshaminy Creek Watershed, Tohickon Creek Watershed, Skippack Creek Watershed, or East Branch Perkiomen Creek Watershed as delineated in Appendix G[1] which is hereby adopted as part of this chapter.
[1]
Editor's Note: Appendix G is included as an attachment to this chapter.
B. 
This chapter shall apply to temporary and permanent stormwater management facilities constructed as part of any of the regulated activities listed in this section. Stormwater management and erosion and sedimentation control during construction activities, which are specifically not regulated by this chapter, shall continue to be regulated under existing laws and ordinances.
C. 
This chapter contains only the stormwater management performance standards and design criteria that are necessary or desirable from a watershed-wide perspective. 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 applicable ordinances.
D. 
The following activities are defined as "regulated activities" and shall be regulated by this chapter except as exempted by § 134-5 of this chapter:
(1) 
Land development.
(2) 
Subdivision.
(3) 
Prohibited or polluted discharges.
(4) 
Alteration of the natural hydrologic regime.
(5) 
Construction of new or reconstruction of, or addition of new impervious or semi-impervious surfaces (e.g., driveways, parking lots, roads, etc.), except for reconstruction of roads where there is no increase in impervious surface, and/or construction of new buildings or additions to existing buildings.
(6) 
Redevelopment.
(7) 
Diversion piping, or encroachments in any natural or man-made stream channel.
(8) 
Nonstructural and structural stormwater management best management practices (BMPs) or appurtenances thereto.
(9) 
Temporary storage of impervious or pervious material (rock, soil, etc.) where ground contact exceeds 5% of the lot area or 5,000 square feet (whichever is less), and where the material is placed on slopes exceeding 8%.
A. 
Exemptions from any provision permitted by this section shall not relieve the applicant from all other requirements of this chapter.
B. 
General exemptions. The following land use activities are exempt from stormwater management peak rate and plan requirements of this chapter. On all sites where a cumulative area of less than 1,000 square feet of impervious surface since May 8, 2003, is proposed, the applicant is exempt from stormwater management plan submission requirements of § 134-28 of this chapter.
(1) 
Use of land for gardening for home consumption.
(2) 
Agricultural activity when operated in accordance with a conservation plan, nutrient management plan, requirements of 25 Pa. Code Chapter 102, or erosion and sedimentation control plan approved by the Bucks County Conservation District, including activities such as growing crops, rotating crops, tilling of soil, and grazing animals. Installation of new, or expansion of existing, farmsteads, animal housing, waste storage, production areas, or other areas having impervious surfaces shall be subject to the provisions of this chapter unless exempt pursuant to § 134-5C.
(3) 
Forest management and timber operations following the Department of Environmental Protection's management practices contained in its publication "Soil Erosion and Sedimentation Control Guidelines for Forestry" and operating according to the requirements of 25 Pa. Code Chapter 102, and which have zoning permit approval from Hilltown Township.
(4) 
Public road replacement, replacement paving, repaving and/or maintenance.
(5) 
Any aspect of BMP maintenance to an existing SWM system made in accordance with plans and specifications approved by the Township.
C. 
All regulated activities as described in § 134-4 of this chapter shall comply with the stormwater management requirements hereof except those activities meeting criteria listed in stormwater management peak rate exemption criteria tables below. Those activities listed in stormwater management peak rate exemption criteria tables are, to the extent stated herein, exempt from peak rate control provisions of § 134-12 but are subject to compliance with § 134-5E. This requirement shall apply to the total development even if development is to take place in phases. The starting point from which to consider tracts as parent tracts is May 8, 2003. All impervious surface area constructed on or after May 8, 2003, shall be considered cumulatively. Impervious surface existing on the parent tract prior to May 8, 2003, shall not be considered in cumulative impervious area calculations for exemption purposes. An exemption shall not relieve the applicant from implementing such stormwater control measures and erosion control measures as are necessary to protect health, safety, and property.
(1) 
Table 134-5.1 and Table 134-5.2 Stormwater Management Peak Rate Exemption Criteria. Regulated activities included within § 134-4 are exempt from peak rate control requirements of § 134-12 where the amount of impervious surface and proposed location on a parcel conforms to the following tables:
Table 134-5.1
Total Parcel Area
(acres)
Maximum Impervious Surface Area
(square feet)
<0.5
1,200
0.5 to 1.0
2,500
>1.0 to 2.0
4,000
>2.0 to 5.0
5,000
>5.0
7,500
Maximum amount of the impervious surface area permitted pursuant to Table 1 within a setback (excluding driveway access) measured from the downslope property boundary shall conform to the following table:
Table 134-5.2
Setback*
(feet)
Maximum Impervious Surface Area Permitted Within the Setback
(square feet)
10
None permitted
20
1,000
50
2,500
100
4,000
200
5,000
500
7,500
*
The minimum setback distance is measured between the proposed impervious area (excluding driveway access) and/or stormwater control/structure discharge point to the downslope property boundary. The maximum allowable impervious surface area is the amount of impervious surface area permitted within the setback distance. For example: a total of 4,000 square feet of impervious surface is permitted within the 100-feet setback, of which none is permitted within the ten-foot setback, not more than 1,000 square feet is permitted within the twenty-foot setback, and not more than 2,500 square feet is permitted within the fifty-foot setback.
In lieu of meeting the minimum distance criteria, the applicant may provide documentation from a design professional that the increased flows from the site leaves the site in the same manner as the predevelopment condition and that there will be no adverse affects to properties along the path of flow(s). The Township may require the above-referenced documentation on any site including a site meeting the minimum distance or parcel size criteria when deemed necessary at the sole discretion of the Township.
(2) 
Construction or reconstruction of buildings or additions to existing buildings or other impervious surface (activities regulated pursuant to § 134-4) are exempt where the following conditions are met:
(a) 
An area of impervious surface is removed from the site equal to, or in excess of, the proposed impervious surface area.
(b) 
The area where existing impervious surface is removed pursuant to Subsection C(2)(a) above must be restored with a minimum of 12 inches of topsoil and stabilized pervious groundcover.
(3) 
Lot line adjustment subdivisions are exempt when no increase in impervious surface is proposed.
D. 
Basic procedure for existing single-family dwelling lots. Individual residential construction projects on existing single-family lots that are classifed as regulated activities which result in less than 2,500 square feet of new impervious area (including the building footprint, driveway, sidewalks, swimming pools, patios, and parking areas) and less than 5,000 square feet of earth disturbance but do not meet exemption criteria of § 134-5C (or are exempt from peak rate reduction requirements but are subject to the additional criteria of § 134-15, § 134-16 or § 134-17) may utilize the procedure within Appendix I[1] to meet requirements of the ordinance and are not required to submit formal stormwater management plans to the Township. This procedure may not be utilized for proposed subdivision or land development.
[1]
Editor's Note: Appendix I is included as an attachment to this chapter.
E. 
Additional exemption criteria.
(1) 
Exemption responsibilities. An exemption shall not relieve the applicant from implementing such measures as are necessary to protect the public health, safety, and property.
(2) 
Drainage problems. Where drainage problems are documented or known to exist downstream of, or is expected from, the proposed activity, the Township may deny an exemption.
(3) 
HQ and EV streams. An exemption shall not relieve the applicant from meeting the special requirements for watersheds draining to high quality (HQ) or exceptional value (EV) waters contained in §§ 134-15 and 134-16 of this chapter.
(4) 
Neshaminy Creek Watershed. An exemption shall not relieve the applicant from meeting volume control requirements contained in § 134-17 for sites located within the Neshaminy Creek Watershed.
F. 
The Township, upon request by the applicant, may grant an exemption from the provisions of this chapter for a project qualifying under § 134-5C. If an exemption is granted, the Township shall require the developer to pay a fee in an amount established by separate resolution of the Board of Supervisors to the Municipal Stormwater Management Capital Fund.
G. 
All applicants seeking an exemption of stormwater management peak rate requirements based upon criteria contained in § 134-5C shall, at a minimum, submit the following documentation for review:
(1) 
Two copies of the completed Township stormwater management application form.
(2) 
Stormwater management review fee and escrow, as established by separate resolution of the Board of Supervisors.
(3) 
Two copies of a plot plan for the parcel, which is the subject of the exemption application, containing, at a minimum, the following information:
(a) 
Property boundaries and area of the site, based on deed information, or field survey.
(b) 
Location map identifying the site relative to streets and other parcels in the vicinity of the site.
(c) 
Location of significant natural and existing man-made features, including wetlands, watercourses, woodlands, steep slopes, structures, parking areas, driveways, utilities, wells, and septic systems within 200 feet of proposed impervious surface, regardless of the location of the property boundary.
(d) 
Location and dimensions of existing and proposed impervious surface and other improvements, with setbacks drawn to relate the location of same to property lines, streets, and existing features.
(e) 
North arrow.
(f) 
Plan scale, as applicable.
(g) 
Information regarding existing/proposed topography and drainage patterns, within 200 feet of proposed impervious surface based on field survey, USGS mapping, and/or field observation.
(h) 
Other information deemed necessary by the Township Engineer to determine compliance with exemption criteria contained in § 134-5.
H. 
The Township may deny or revoke any exemption pursuant to this section at any time for any project that the Township believes may pose a threat to public health and safety or the environment.
Any ordinance or ordinance provision of the municipality inconsistent with any of the provisions of this chapter is hereby repealed to the extent of the inconsistency only.
Should any section or provision of this chapter be declared invalid by a court of competent jurisdiction, such decision shall not affect the validity of any of the remaining provisions of this chapter.
The Board of Supervisors may grant a modification of the requirements of one or more provisions of this chapter if the literal enforcement will exact undue hardship because of peculiar conditions pertaining to the land in question, provided that such modification will not be contrary to the public interest and that the purpose and intent of the ordinance is observed.