(A) For all regulated activities, unless preparation of an SWM site plan is specifically exempted in § 53.041:
(1) Preparation and implementation of an approved SWM site plan is required; and
(2) No regulated activities shall commence until the municipality issues written approval of an SWM site plan which demonstrates compliance with the requirements of this chapter.
(B) SWM site plans approved by the municipality, in accordance with § 53.065, shall be on site throughout the duration of the regulated activity.
(C) The municipality may, after consultation with DEP, approve measures for meeting the state water quality requirements other than those in this chapter, provided that they meet the minimum requirements of, and do not conflict with, state law including, but not limited to, the Clean Streams Law. The municipality shall maintain a record of correspondence with DEP pursuant to this division (C).
(D) For all regulated earth disturbance activities, erosion and sediment control BMPs shall be designed, implemented, operated and maintained during the regulated earth disturbance activities, i.e., during construction, to meet the purposes and requirements of this chapter and to meet all requirements under 25 Pa. Code and the Clean Streams Law. Various BMPs and their design standards are listed in the Erosion and Sediment Pollution Control Program Manual (E&S Manual) 2, No. 363-2134-008 (April 15, 2000), as amended and updated.
(F) Impervious areas:
(1) The measurement of impervious areas shall include all of the impervious areas in the total proposed development even if development is to take place in phases;
(2) For development taking place in phases, the entire development plan must be used in determining conformance with this chapter; and
(3) For projects that add impervious area to a parcel, the total impervious area on the parcel is subject to the requirements of this chapter; except that the volume controls in § 53.042 and the peak rate controls of § 53.043 do not need to be retrofitted to existing impervious areas that are not being altered by the proposed regulated activity.
(G) Stormwater flows onto adjacent property shall not be created, increased, decreased, relocated or otherwise altered without written notification to the adjacent property owner(s). A copy of such notice shall be provided to the borough prior to issuance of the stormwater management permit. Such stormwater flows shall be subject to the requirements of this chapter.
(H) All regulated activities shall include such measures as necessary to:
(1) Protect health, safety and property;
(2) Meet the water quality goals of this chapter, as stated in § 53.003, by implementing measures to:
(a) Minimize disturbance to floodplains, wetlands, wooded areas and existing vegetation;
(b) Maintain or extend riparian buffers;
(c) Avoid erosive flow conditions in natural flow pathways;
(d) Minimize thermal impacts to waters of this Commonwealth;
(e) Disconnect impervious surfaces by directing run-off to pervious areas, wherever possible; and
(f) Minimize soil disturbance and compaction. Topsoil, if removed, shall be replaced to a minimum depth equal to its depth prior to removal or a four inch minimum depth, whichever is greater. The applicant is not required to install greater than eight inches of topsoil unless required by the design and/or plant material.
(3) To the maximum extent practicable, incorporate the techniques for low impact development practices described in the Pennsylvania Stormwater Best Management Practices Manual (BMP Manual).
(I) The design of all facilities in areas of carbonate geology or karst topography shall include an evaluation of measures to minimize adverse effects, including hydro-geologic studies if required by the municipality.
(J) Infiltration BMPs shall be spread out, made as shallow as practicable, and located to maximize use of natural on-site infiltration features while still meeting the other requirements of this chapter. In addition, infiltration BMPs shall include pre-treatment BMPs where appropriate.
(K) Normally dry, open-top storage facilities, designed as such, shall completely drain both the volume control and rate control capacities over a period of time not more than 96 hours from the end of the design storm. Infiltration facilities shall be designed to infiltrate in not less than 24 hours, however, any designed infiltration at such facilities is exempt from the minimum 24-hour standard, i.e., may infiltrate in a shorter period of time, so long as none of the stormwater flowing into the infiltration facility is discharged directly into the surface waters of the Commonwealth. (Inordinately rapid infiltration rates may indicate the presence of large fractures or other conditions for which an additional soil buffer may be required.)
(L) The design storm volumes and precipitation intensities to be used in the analysis of discharge or run-off shall be obtained from the Precipitation-Frequency Atlas of the United States, Atlas 14, Volume 2, Version 3.0, U.S. Department of Commerce, National Oceanic and Atmospheric Administration (NOAA), National Weather Service, Hydrometeorological Design Studies Center, Silver Spring, Maryland, in effect at the time of application. NOAA’s Atlas 14 can be accessed at: http://hdsc.nws.noaa.gov/hdsc/pfds/.
(M) For all regulated activities, SWM BMPs shall be designed, implemented, operated and maintained to meet the purposes and requirements of this chapter and to meet all requirements under 25 Pa. Code, the Clean Streams Law and the Stormwater Management Act.
(N) Various BMPs and their design standards are listed in the BMP Manual.
(O) For any new development or redevelopment, stormwater BMPs shall be utilized to reduce the discharge of nitrogen, phosphorus and sediment to the maximum extent practicable.
(Ord. 2013-2, passed 10-7-2013)