Year 1 sampling completed in effort to measure how well bioretention BMPs remove microplastics in runoff

SCCWRP and its partners have completed the first season of wet-weather sampling for a two-year study investigating the effectiveness of bioretention BMPs (best management practices) at removing microplastics pollution from runoff.

During the 2023-2024 wet-weather season, researchers leveraged the Southern California Stormwater Monitoring Coalition’s Regional BMP Monitoring Network to collect runoff entering and exiting six bioretention BMPs across Southern California.

While the runoff sampling was completed in April, researchers will return to the BMP sites this summer to sample the bioretention media as well.

The study’s goal is to understand how specific characteristics of different types of BMP engineered media influence the removal of microplastics from runoff. Results are expected to be released in late 2025.