Monday the general manager of the largest water district in the state, possibly in the country, maybe the world, came to the little Valley Center Municipal Water District board room to defend his agency, the Metropolitan Water District of Southern California, from the ankle biting attacks of the much smaller San Diego County Water Authority. He also came to update Valley Center about the state of water supply in the Golden State. Representatives of the two agencies have been team tagging each other at board rooms around San Diego County for several weeks.