Todd Steiner and Paola Bouley

RECENT DECISIONS by Marin supervisors may destroy any chance of saving the critically endangered coho salmon from extirpation in Marin's most important watershed, the San Geronimo Valley.

In the past month, supervisors have overturned two unanimous decisions by the Planning Commission, which will allow building in the "protected" Stream Conservation Area. The decisions allow the permanent destruction of streamside habitat critical to the survival of our beloved coho salmon and set an unpardonable precedent that cannot be allowed to stand.

A landowner will be allowed to build his "dream house" not to replace, but to augment his current dwelling, by adding an additional home and garage totaling 4,000 square feet inside the 100-foot streamside setback.

Why does this matter? Streams are the lifeblood of terrestrial ecosystems, just like our own circulatory systems are to our bodies. They sustain all life and provide the vast majority of the potable water for Marin, which comes from dammed portions of Lagunitas and Nicasio Creeks. Below these dams, streams transport stormwaters to the sea, preventing floods and stagnant waters that harbor mosquitoes and water-borne illnesses.

Streams are the migratory pathways and spawning and nursery habitat for salmon, who also transport nutrients from the ocean environment back onto land, helping sustain healthy forests and wildlife populations.

Just like our own circulatory system, stream ecosystems only work if they are attached to a functioning system. In the case of streams, that includes a necessary buffer zone of forest habitat.

Without these forests, streams do not provide crucial ecosystem services to us such as clean water and protection from flooding. Without trees, the banks erode, doing significant damage to our adjacent properties. Bank failures also cause siltation that harm salmon and other aquatic wildlife. And without these forests, young salmon cannot survive, as they need the insect-prey that falls from the tree canopies, the cool water their shade provides and the complex in-stream refuge structures.

Besides salmon, 225 species of birds, mammals, reptiles and amphibians in California depend on streamside habitat for their survival, yet nearly 95 percent of this habitat has been destroyed.

In 1994, the Marin Community-wide Plan recognized the importance of streamside habitats and called for their protection. Unfortunately, for nearly 10 years these policies were never codified as regulations, as required by law. In 2002, supervisors passed a very weak Stream Conservation Area ordinance, which called for 100-foot setbacks from streambanks in West Marin.

Unfortunately, for a small minority of Marin residents, that may mean that if they want to build their "dream homes," they need to purchase property suitable for accommodating their desires, or modify their "dreams" to accommodate the ecological limitations of sensitive properties. In this way, the collective "dreams" (as codified in the legal policies set forth in the San Geronimo Valley Plan) of the community, that allow for healthy streams and healthy salmon populations to co-exist with humans, will be maintained.

Regrettably, the current ordinance has enough loopholes to drive a bulldozer through. In fact, in the San Geronimo Valley, which may have the densest population of critically endangered wild coho salmon left anywhere in California, and is under the greatest threat from development, the loopholes in the ordinance threaten to make protections meaningless for more than two-thirds of all streamside parcels.

While Salmon Protection and Watershed Network volunteers spend thousands of hours each year repairing damage to riparian habitat, as do other Marin organizations, and government agencies spend millions of our tax dollars on stream repairs in Marin, our supervisors continue to approve more developments that cause new harm.

If we want to leave a legacy of environmental protection in Marin that includes healthy populations of coho for our children and grandchildren, then we must make supervisors live up to their environmental sustainability rhetoric by creating and enforcing meaningful stream protection regulations.

We need your help. Contact us at spawn@SpawnUsa.org or visit www.SpawnUSA.org.

Todd Steiner is executive director and Paola Bouley is watershed biologist for SPAWN, the Salmon Protection And Watershed Network. They serve individually or collectively on the Lagunitas Creek Technical Advisory Committee, Tomales Bay Watershed Council, Cordell Bank National Marine Sanctuary Advisory Council and the Tomales Bay Association..