The Sonoma County Board of Supervisors, who also serve as the Board of Directors for the Sonoma County Water Agency, voted today to approve a Joint Exercise of Powers Agreement with Mendocino County Inland Water and Power Commission to form the Eel-Russian Project Authority.  The new entity will have the power to negotiate with the Pacific Gas and Electric Company (PG&E) as the utility moves ahead with plans to surrender operations of the Potter Valley Hydroelectric Project and to decommission the Scott and Cape Horn dams on the Eel River. The new authority will also have the legal capacity to own, construct and operate a new water diversion facility near the Cape Horn dam.  … The Potter Valley Project, currently owned and operated by PG&E, has been diverting water from the Eel River into the Russian River watershed for more than a century, playing a critical role in supplying water for agriculture, homes, and instream flows to benefit aquatic ecosystems and threatened salmonids in Mendocino and Sonoma counties.