Slide 27 of 52
Notes:
The previous slides have provided a broad overview of the different types of sand filters and the unique features associated with each. The following slides are intended to provide guidance about key design elements that generally apply to all of the filter types. Specifically, guidance is provided on flow regulation, pretreatment, filter media, overflow, construction specifications, and maintenance.
The design objective of filters is to capture and divert the water quality volume (WQV) to the filter and �bypass� larger storms to the downstream storm drainage system or receiving water. A flow diversion structure must be able to accommodate these larger flows as well as the water quality storm. Sand filters should be located where they can intercept as much of the site impervious area as possible and where discharge to the primary conveyance system is feasible.
Two methods for diverting the WQv include Computing a peak discharge (Qp) for the water quality storm and: (1) utilizing an diversion structure upstream and within the drainage network or, (2) incorporating the diversion structure within the treatment practice itself.
