How do you keep a river in a 10,000 km2 watershed fishable, swimmable, and drinkable? That was the theme of Water Day, the annual outreach event of the volunteer environmental monitoring group The Eel River Recovery Project. This year graduate and undergraduate students from UC Berkeley and the Angelo Coast Range Reserve Critical Zone Observatory (CZO) also took part in the event. The day was filled with presentations, question and answer panels, and hands on exhibits. UC Berkeley’s Keith Bouma-Gregson, a Ph.D. student in the Department of Integrative Biology, gave a presentation on algal ecology and how to identify toxic cyanobacteria, which proliferates in the river during late summer. The CZO students also had an exhibit table filled with algae, insects, fish and lots of microscopes. Hundreds of people came to Water Day from throughout Humboldt and Mendocino Counties, and CZO students were able to answer questions about aquatic ecology and show people the diverse types of organisms that live below the surface of the river.