Watershed Spotlight: Meet the Sweetwater

Welcome to our first installment of Watershed Spotlight! Coming up, we’ll be highlighting some of our favorite San Diego County watersheds (hint: it’s all of them) in a new feature series on these amazing places we call home.

Need a quick refresher on the definition of a watershed? Start here.


The Sweetwater Watershed is one of three watersheds that drain into San Diego Bay. Its main waterbody, the Sweetwater River, has its headwaters up in Cuyamaca Rancho State Park and drains parts of Viejas Tribal Land, Alpine, Pine Valley, Lemon Grove, La Mesa, Spring Valley, El Cajon, Bonita, Chula Vista, and National City, before reaching the Bay. 


The watershed includes some of our favorite hiking trails, two national wildlife refuges, two reservoirs, and a plethora of parks providing important habitat for plants and animals as well as recreational opportunities for us humans. Our volunteer monitors have been visiting two sites in this watershed since 2009, keeping tabs on water quality by measuring ambient stream conditions, nutrients, and bacteria.  That’s nearly 10 years of data that is helping us understand and protect our water resources. 


Learn more about our Sweetwater River monitoring and check out recent data here!