WHY SHOULD anyone care if California salmon, or local fishermen, go the way of the dodo? Can't we just buy fish from Alaska? And what's wrong with the farmed stuff, anyway?

Because of economic suffering in the Central Valley, some are calling for an end to environmental protections for California's once-mighty salmon runs. At the center of the salmon debate is the fate of the Bay-Delta Estuary, the West Coast's largest and most important estuary. Estuaries are the interconnection between land, rivers and ocean, providing spawning and nursery habitat for commercial and recreational fisheries as well as birds, waterfowl and wildlife. Losing that diversity, turning rivers into canals that no longer support life, risks turning our estuary into a degraded system with more invasive and pest species while local fish, birds, invertebrates and wildlife die off.

Wild salmon is valuable as a harvestable, healthy and tasty food commodity loaded with omega-3 fatty acids. But the health and viability of local salmon has everything to do with the health and viability of the aquatic ecosystem that surrounds us. As biologists will attest, if you want to measure the health of aquatic ecosystems, you need to measure fish.

As salmon begin to go extinct, it sets off a chain reaction in the natural community and a chain reaction for people impacted by loss of revenue from salmon and sport fishing, farming and tourism in the bay delta. It also has major implications for the costs and quality of California's water supply.

As we ignore these warning signs and call for more water and less fish, we miss an important opportunity to prepare for a smarter water future. We have water in California, but an ancient system of rights and distribution leads to some farmers paying higher prices for limited supplies, while others receive full allocations at relatively low rates. Some urban areas use 100 gallons per person per day, while others use more than 300.

We have tremendous potential to grow "new" water supplies with recycling and conservation. Innovators like PureSense are helping growers realize more profit per acre through the efficient use of water. Hydropoint is helping eBay, Lockheed Martin, Cisco, Amazon and Advanced Micro Devices use less water in landscaping. There are reasonable answers to these conflicts if we avoid getting trapped in rhetorical divides.

We could pump water out of this estuary indiscriminately as some are calling for, but at some point, California would still bump up against limitations in the amount of water in its system, the rising costs of extracting and moving it, and increasing droughts from climate change.

We could, in other words, destroy what is left of the most important estuary on the West Coast and still not solve the economic problems facing much of the Central Valley. Sooner or later California is going to have to change how it uses water. We can do it before we lose our salmon, or after.

Cynthia Koehler is a consulting attorney for the Environmental Defense Fund, a national nonprofit organization.

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