Underlying the long-running battles between proponents and opponents of the proposed Poseidon Resources ocean desalination plant is an ideological war between two roughly defined factions: conservationists and free-marketeers. The Orange County Water District(OCWD), which manages theSanta Ana River and the Orange County Groundwater Basin (a collection of aquifers containing 60 million acre-feet of water), is ground-zero in that war. (The OCWD supplies 75 percent of the drinking water for 2.4 million residents of north Orange County).