Laboratory Testing Guidelines for Certification of Manufactured Stormwater BMPs

For the past decade, manufactured stormwater best management practices (BMPs) have been widely used in urban areas to remove suspended solids from stormwater runoff to meet the local and federal government agencies' standards. The ASCE/EWRI Task Committee on Guidelines for Certification of Manufactured Stormwater BMPs formed a subcommittee to develop the laboratory testing guidelines. The focus of this subcommittee has been on developing laboratory testing guidelines to assess the efficiency of the devices used for physical separation of the full spectrum of stormwater-borne non-dissolved solids. In general, these devices include hydrodynamic separators and filters. After reviewing the protocols developed by organizations, but not limited to, the state of Washington Technology Assessment Protocol-Ecology (TAPE), the state of Wisconsin Method for Predicting the Efficiency of Proprietary Storm Water Sedimentation Devices, the TARP Protocol for Stormwater Best Management Practice Demonstrations, the subcommittee utilized the experience obtained from the laboratory tests conducted on these devices and employed the material in the existing protocols to develop the testing guidelines. These guidelines are designed to conduct robust laboratory testing with stated repeatability. The guidelines encompass three separate series of tests for addressing three different processes: (1) Testing to determine the efficiency of hydrodynamic separators in removing suspended sediments, (2) testing to quantify sediment retention of hydrodynamic separators, and (3) testing to determine the efficiency of filters in removing suspended solids.