A. For design and applicability of non-structural BMPs refer to Chapter 5 of the “Pennsylvania Stormwater Management Practices Manual”, December 2006, as amended. For the non-structural BMPs proposed, the applicant shall utilize and submit appropriate checklists included in Chapter 8, Section 8.8 of the “Pennsylvania Stormwater Best Management Practices Manual”, December 2006, as amended to demonstrate that the BMPs are applicable to the project and to determine the amount of volume or peak rate credit is applicable.
B. The applicant for major subdivision or land development approval shall demonstrate that stormwater management is designed in the following sequence to minimize the increase in stormwater runoff and degradation of water quality:
1. Prepare an Existing Resource and Site Analysis Plan (ERSAP), as required by the Subdivision and Land Development Ordinance, showing environmentally sensitive areas including, but not limited to, steep slopes, ponds, lakes, streams, wetlands, hydric soils, vernal pools, floodplains, riparian corridors, hydrologic soil groups A, B, C, and D, “prime agricultural soils” (prime farmland and farmland of statewide importance as designated in the soil survey of Bucks County), woodlands, surface waters regulated by the State or Federal Government, any existing recharge areas, and any other requirements outlined in the Subdivision and Land Development Ordinance.
2. Prepare a draft project layout avoiding sensitive areas identified in Section 304.B.1 (and as further defined by Section 508 of the Zoning Ordinance) and minimizing total site earth disturbance. The ratio of disturbed area to the entire site area and measures taken to minimize earth disturbance shall be included in the ERSAP.
3. Identify site specific existing conditions, drainage areas, discharge points (points of interest), recharge areas, and hydrologic soil groups A and B.
4. Evaluate Nonstructural Stormwater Management Alternatives.
a. Minimize earth disturbance.
b. Minimize impervious surfaces.
c. Break up large impervious surfaces.
5. Satisfy volume control objective (Section 303).
6. Satisfy stream bank erosion protection objective (Section 307).
7. Determine the Management (Release Rate) District within which the site is located (refer Appendix B) and conduct a predevelopment runoff analysis.
8. Prepare final project design to maintain predevelopment drainage areas and discharge points, to minimize earth disturbance and impervious surfaces, to reduce runoff to the maximum extent possible, and to minimize the use of surface or point discharges.
9. Conduct a proposed conditions runoff analysis based on the final design and to meet the release rate and in turn the overbank flow and extreme event requirements (Section 307).
10. Manage any remaining runoff through treatment prior to discharge, as part of detention, bioretention, direct discharge or other structural control.
11. Prepare a stormwater management operation and maintenance plan consistent with requirements of Section 702 that ensures the long term viability of the stormwater control facilities.
(Ord. 186, passed 9-12-2017)