An Update on Draft ASCE Monitoring Guidelines for Monitoring Stormwater Gross Solids

Historically, evaluations of stormwater Best Management Practices, (BMPs), have focused on dissolved and suspended pollutants because the sampling methods were adapted from people's experience with wastewater treatment plants. Therefore, pollutants were sampled in the influent and effluent water column using grab samples or autosamplers, and flow measurements were made using velocity or weir measurements. But, stormwater pollutants differ from wastewater by being intermittent in nature and often having high volumes of gross pollutants in the storm runoff that can not be measured using autosamplers and standard techniques. New methods are being developed that measure gross pollutants in addition to the pollutants in the water column.