Work With Nature, Not Against

Yesterday’s monuments to progress can become today’s roadblocks as times, conditions and philosophies change.

It is in this spirit that Ventura County supervisors are cautiously exploring the wisdom of removing the Matilija Dam, which blocks Matilija Creek before it joins the Ventura River northwest of Ojai.

When it was built in 1948, the dam was designed to capture sediment to reduce flood risks downstream and to store water for area growers and residents. It worked too well. Its reservoir is now nearly full of sand and has little room for water.

In 50 years, much has been learned about the dynamics of water and sand and the conflicting needs of people and fish. We now know:

* Because the dam waylays sediment on its way to the sea, beaches to the south are starved of a natural source of sand to replenish that carried away by ocean waves. One result is persistent erosion that imperils the beach and bike path behind the Ventura County Fairgrounds and continues down the coast.

* Because the dam is too high for fish to cross, it blocks 20 miles of spawning grounds that might help save the endangered steelhead, an oceangoing trout that used to thrive in the river. A spokesman for the National Marine Fisheries Service has said removing Matilija Dam would be “one of the most beneficial actions that could be taken to help rebuild the steelhead population on the Ventura River.”

Damming rivers to make nature do man’s bidding was an important part of how the West was won. But now, amid a growing desire to work with nature rather than against it, the monumental structures are getting a second look all across the country.

Removing dams should be done as cautiously as building them. Whether the Matilija Dam should be removed all at once, in stages over a number of years or not at all deserves close study. The supervisors rightly encouraged further exploration of the idea with input from public works and flood-control specialists. That’s the only way to determine whether the Matilija Dam is doing more harm or good.