(A) For all regulated activities, unless preparation of an SWM site plan is specifically exempted in § 154.026:
(1) Preparation and implementation of an approved SWM site plan is required.
(2) No regulated activities shall commence until the township issues written approval of an SWM site plan, which demonstrates compliance with the requirements of this chapter.
(B) SWM site plans approved by the township, in accordance with § 154.045, shall be on site throughout the duration of the regulated activity.
(C) The township 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.
(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 (e.g., 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), No. 363-2134-008 (April 15, 2000), as amended and updated.
(E) For all regulated activities, implementation of the volume controls in § 303 is required.
(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 stages.
(2) For development taking place in stages, the entire development plan must be used in determining conformance with this chapter.
(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.
(G) Stormwater flows onto adjacent property shall not be created, increased, decreased, relocated, or otherwise altered without written notification of the adjacent property owner(s). 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 by implementing measures to:
(a) Minimize disturbance to floodplains, wetlands, and wooded areas.
(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 runoff to pervious areas, wherever possible; and
(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 over karst shall include an evaluation of measures to minimize adverse effects.
(J) Infiltration BMPs should 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.
(K) Storage facilities should completely drain both the volume control and rate control capacities over a period of time not less than 24 and not more than 72 hours from the end of the design storm.
(L) The design storm volumes to be used in the analysis of peak rates of discharge should 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. 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 Storm Water Management Act.
(N) Various BMPs and their design standards are listed in the BMP Manual.
(Ord. 1-2017, passed 7-25-2017)