3819 HOYT AVE 2025-07-28 - Laserfiche WebLink

E. CONVEYANCE SYSTEM ANALYSIS Maximum Flows from on-site developed area: For this project the entire 0.15 acres of impervious was analyzed for the peak 100-year flow rate to ensure the system as designed could handle the expected flows. Using the WWMH3 software a peak 100-year flow rate of 0.10 cfs was calculated. Using Manning's Equation the minimum conveyance capacity of the new storm pipe as designed is 0.8 cfs which is eight times greater than the flows from the entire basin. Therefore, this system has more than adequate capacity for the expected flows. 7. SWPPP MINIMUM REQUIREMENT#2: CONSTRUCTION STORMWATER POLLUTION PREVENTION (SWPPP) 1: Mark Clearing Limits One of the first steps in the "Construction Sequence" included on the clearing and grading plan sheets is for a surveyor to stake the limits of clearing and to have construction flagging/fencing or silt fencing placed along the limits prior to any other construction activity. 2: Establish Construction Access The SWPPP calls for the proposed construction entrance to be installed as the second step after the staking of clearing limits. A detail is provided on the plans. 3: Control Flow Rates This project will retain as much existing vegetation as possible and will be re-vegetated after grading is complete. In addition, the swale will be used as an interceptor swale during construction to trap sediment and attenuate flows. Therefore, the flow restrictors will be in place to regulate runoff during construction. This will protect the downstream system from higher flows during construction. 4: Install Sediment Controls This site and SWPPP proposes to construct a construction entrance and silt fencing to collect and contain the sediment on this site. In addition, inlet filters will be installed in the new catch basins on the site. These features are intended to minimize the opportunity for sediment to leave the site via stormwater or on vehicles. The construction of these features is one of the first items required in the "Construction Sequence". Mulch will also be used on the exposed soil as necessary to limit erosion. 5: Stabilize Soils The "Construction Sequence" and "TESC Notes" call for the stabilization of soils that remain unworked for certain lengths of time based on the time of year. Stabilization techniques may include but not limited to mulching, plastic sheeting or hydroseeding, notes have been added to the plan regarding protection for the stock pile area if necessary. 6: Protect Slopes Hoyt Parking Lot 12-0808 Oct.2012 Page-14