The Volcan Mountain Range Watershed is a key water source for San Diego and its water flows directly to the Pacific Ocean. It is vital to understand how the presence of microplastic in mountain watersheds can alter the dependent downstream communities.

Four sites across the San Dieguito Watershed and five sites across the San Diego Watershed were sampled for microparticle contamination. Each site represented a different portion of the watersheds, whether it was close to a high mountain spring, along a polluted affluent, or even the Pacific Ocean.

While there was no trend of contamination throughout the watersheds, microparticle pollution was evident across geographic space. This project served to predominately engage the community in and around Volcan Mountain, the San Dieguito Watershed, and the San Diego Watershed in understanding how and when micro-pollutants are entering important water sources. Through citizen science and outreach, participants received hands on experience with biology and pollution science, walking away with a deeper understanding of the place around them.