General design and performance criteria.

A. The applicant shall consult the Town of Webster's Design Criteria, the New York State Stormwater Management Design Manual and the New York Standards and Specifications for Erosion and Sediment Control for standards and specifications related to stormwater management design criteria. Stormwater management practices that are designed and constructed in accordance with these technical documents shall be presumed to meet the standards imposed by this article. If there is a conflict between any of the standards, the more stringent standard shall apply. Where stormwater management practices are not in accordance with technical standards, the applicant or developer must demonstrate equivalence to the technical standards set forth in this section and § 289-22 of this article, and the SWPPP shall be prepared by a licensed/certified professional.B.

The following design and performance criteria shall be addressed for stormwater management at all sites:(1) All site designs shall establish stormwater management practices to control the peak flow rates of stormwater discharge associated with specified design storms and reduce the generation of stormwater. These practices should seek to utilize pervious areas for stormwater treatment and to infiltrate stormwater runoff from driveways, sidewalks, rooftops, parking lots, and landscaped areas to the maximum extent practicable to provide treatment for both water quality and quantity.(2) All stormwater runoff generated from new development shall not discharge untreated stormwater directly into a jurisdictional wetland or local water body without adequate treatment.

Where such discharges are proposed, the impact of the proposal on wetland functional values shall be assessed using a method acceptable to the Town of Webster. In no case shall the impact on functional values be any greater than that allowed by the Army Corp of Engineers (C.O.E.) or the NYSDEC responsible for natural resources.(3) An attempt shall be made to maintain annual groundwater recharge rates by promoting infiltration through the use of structural and nonstructural methods. At a minimum, an attempt shall be made for annual recharge from the postdevelopment site to mimic the annual recharge from predevelopment site conditions.(4) In order to protect stream channels from degradation, a specific channel protection criteria shall be provided as prescribed in the Town of Webster's Design Criteria and/or the New York State Stormwater Management Design Manual.(5) Stormwater discharges to critical areas with sensitive resources may be subject to additional performance criteria, or may need to utilize or restrict certain stormwater management practices.(6) Stormwater discharges from land uses or activities with higher potential pollutant loadings, known as "hotspots," may require the use of specific structural stormwater treatment practices and pollution prevention practices.(7) Prior to design, applicants are required to consult with the Town of Webster Public Works Department to determine if they are subject to additional stormwater design requirements.(8) The calculations for determining peak flows (WQv) as found in the New York State Stormwater Management Design Manual shall be used for sizing all stormwater management practices.