The Current Magazine Fall 2016 - Page 16

Matilija Dam:

How to pull

the plug?

The case of Matilija Dam in Ventura County illustrates the complexities of dam removal. Built in the 1940s for flood control and irrigation water storage, it was condemned by the 1960s as being structurally unsound.

RESTORATION

The area behind Matilija Dam is now almost completely filled in with sediment, rendering the dam non-functional. It blocks historic runs of endangered Southern California steelhead, and causes the usual problems of high water temperatures, an altered flow regime, and most notably, problems with sediment throughout the lower watershed. The dam is owned by the Ventura County Watershed Protection District.

Southern California steelhead evolved to survive in warmer waters than other steelhead populations, making this a particularly valuable population to protect in times of climate change.

They are extremely endangered, with only an estimated 500 individuals remaining. Opening up access to spawning and rearing habitat above this dam will expand critical steelhead habitat to help bolster population numbers in the watershed and region.