The River Foundation supports clean-ups all year long including the mammoth Great Texas River Clean- Ups in the spring and fall held in conjunction with the City of San Marcos and Keep San Marcos Beautiful. Canoe and diving clubs from all over Texas, civic groups, student organizations and the public participate in this massive clean up from the headwaters to the confluence of the Guadalupe, a stretch of 90 miles. With a thousand volunteers, the clean ups now cover the whole watershed, the Blanco River and and parts of the Plum Creek watershed
Keep San Marcos Beautiful also conducts a monthly Hot Spot Clean Up, the first Saturday of every month at different spots around the city needing attention.
The River Foundation is also able to help smaller groups with needed clean ups during the summer months when heavy recreational use leaves behind lots of trash along the banks.