East Bay Regional Park District – www.ebparks.org
The East Bay Regional Parks district seeks to preserve wetlands and open areas for environmental preservation and low impact use. The park district operates 59 parks and more than 1,100 miles of trails in its two-county jurisdiction. You can do trail work in various park areas from March to October each year (18-10 projects/year on Saturdays). East Bay Regional Park also offers frequent shoreline cleanups for small or large groups.
The East Bay Regional Park District is a system of beautiful parklands and trails in Alameda and Contra Costa counties east of San Francisco. The system comprises 121,030 acres in 73 parks, including over 1,250 miles of trails. We acquire, manage, and preserve natural and cultural resources for all to enjoy now and into the future. Their parks are ideal for healthful recreation and environmental education. They invite you to enjoy hiking, 
biking, picnicking, horseback riding, camping, fishing, golfing, boating and nature study in our parks.
The East Bay Regional Park District will preserve a priceless heritage of natural and cultural resources open space, parks and trails for the future and will set aside park areas for enjoyment and healthful recreation for generations to come. An environmental ethic guides them in all that they do
They will acquire, develop, manage, and maintain a high quality, diverse system of interconnected parklands which balances public usage and education programs with protection and preservation of our natural and cultural resources
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