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through a 48 inch outlet pipe that connects to the existing storm sewer outlet system and ultimately discharges to Cazenovia Creek. The stormwater management facilities have been designed to satisfy the requirements of both the Town of West Seneca and the NYSDEC. The overall stormwater management system, including water quality treatment and peak flow control, has been designed in accordance with Chapters 4 and 9 of the NYSDEC Stormwater Management Design Manual. Water Quality & Runoff Reduction Volume: The proposed wet pond provides 100 percent of the required Water Quality Volume (WQv) treatment for the redevelopment. See the Stormwater Drainage Calculations for additional information. The project does not create any new impervious area, all proposed improvements are classified as disturbed impervious area and are therefore subject to the 25 percent WQv treatment requirement. Because no new impervious cover is being created, no Runoff Reduction Volume (RRv) is required for the project. The NYSDEC Stormwater Management Design Manual requires a five-step process for Stormwater Management Planning as outlined in Chapter 3. The five steps include: 1. Site planning to preserve natural features and reduce impervious cover. • Existing vegetation to remain shall be protected from construction activities. 2. Calculation of Water Quality Volume (WQv=RRv) for site. • See Stormwater Drainage Calculations. 3. Incorporation of Green Infrastructure techniques and standard SMPs with Runoff Reduction Volume (RRv) capacity. • The proposed wet pond provides 100 percent of the required Water Quality Volume (WQv) treatment for the redevelopment. See the Stormwater Drainage Calculations for additional information. 4. Use of standard SMPs where applicable, to treat the portion of water quality volume not addressed by green infrastructure techniques and standard SMPs with RRv capacity. • The project does not create any new impervious area, all proposed improvements are classified as disturbed impervious area and are therefore subject to the 25 percent WQv treatment requirement. Because no new impervious cover is being created, no Runoff Reduction Volume (RRv) is required for the project. 5. Design of volume and peak rate control practices where required. • See Stormwater Drainage Calculations. The NYSDEC Stormwater Management Design Manual requires (5) five different criteria be considered when designing a stormwater management system. Those criteria are Water Quality, Runoff Reduction Volume, Channel Protection, Overbank Flooding and Extreme Storm Protection. Below is a summary of each item and how it is incorporated into this project. The NYSDEC requires stormwater runoff from development sites to be treated through approved green infrastructure practices and stormwater management practices (SMPs) to improve water quality and better replicate predevelopment hydrology. As a redevelopment project, only 25% of the Water Quality Volume (WQv) generated from disturbed impervious areas is required to be treated in accordance with the NYSDEC Stormwater Management Design Manual. Because the proposed redevelopment results in a net decrease in impervious area, all new West Seneca Exchange 07/20/2026 Page 13 of 24 Page 834 of 1174