Rock Creek Conservancy 4825 Cordell Ave, Bethesda, MD20814 Rock Creek Conservancy is a nonprofit environmental organization based on Cordell Avenue in Bethesda. The group,…More formerly known as Friends of Rock Creek's Environment (FORCE), works to protect, educate and restore Rock Creek and its surrounding areas. The creek meanders 33 miles through the Washington metropolitan area, crossing federal lands as well as district, city, county, and state boundaries. The group provides educational outreach, advocacy and special programs, including cleanup events, community service and more. The Rock Creek encompasses parks, plants, animals, trees and more. Check the main site for details on the area or for information on how to donate, volunteer or get involved.