Laboratory study on the clogging potential of a hybrid best management practice

A hybrid BMP (best management practice) is a technology that incorporates several functions, such as infiltration, filtration, and retention in a single system. Nevertheless, such functions are still prone to clogging and may require frequent maintenance. Clogging due to the deposition of sediments over time reduces the porosity and infiltration rate during monitoring despite being a well-designed system. The objective of this study was to determine the clogging potential of a hybrid BMP. The clogging tests using filter media columns were undertaken to determine the physical clogging processes and the factors that affect clogging. Based on the results, hydraulic loading and sediment mass loading influenced the generation and duration of clogging in the filter media. Early development of premature clogging was observed at the initial 25% of the depth due to the retention of sediment particle sizes ranging between 50 and 250 μm. It was suggested that scraping of the first 25% depth of the media can be performed to maintain the hydraulic capacity of the stormwater filters. Although laboratory studies do not entirely demonstrate the actual field conditions, insights from this study can provide valuable understanding on how such system would perform over time.