Estuary News

October 2021

Reconnecting Mill Creek to its Watershed

For thousands of years, Coho salmon and steelhead returned to spawn in the cold waters of Mill Creek, part of the San Vicente watershed in the mountains above Santa Cruz. This ended when a mining and logging company dammed the creek in the early 20th century. Now, an ambitious conservation initiative has succeeded in removing the dam, bringing people together across local land trusts, Native American groups, regional agencies, and researchers from multiple universities. Valentin Lopez, chairman of the Amah Mutsun Tribal Band, spoke about the dam removal in his session of the Estuary Summit.

Mill Creek Dam removal. Photo: Ian Bornarth, courtesy Sempervirens Fund.

The San Vicente Redwoods is a large stretch of forest sitting above the coastal town of Davenport. Following its 2011 purchase by a coalition including the Sempervirens Fund, Peninsula Open Space Trust, Save the Redwoods League, and Land Trust of Santa Cruz County, efforts have been underway to restore both the forest and the creek. The watershed is considered unique for its accessibility to migratory fish in the Pacific and an underlying karst limestone cave system which produces a high flow of cold water.

But the dam couldn’t come down because it supported a pipe bringing water to the town of Davenport. Circumstances changed after the 2020 CZU fire moved through the area, “burning the pipe like a wick, melting it right off the dam,” says Matt Shaffer, communications officer with the Sempervirens Fund. The replacement pipeline was moved to a new location, and the groups got the green light to take the dam down.

“We’re very glad to have worked on [the dam removal] with other partners,” said Valentin Lopez of the Amah Mutsun Land Trust. The Amah Mutsun Tribal Band are the descendants of Mutsun and Awaswas-speaking peoples who occupied much of the current Monterey Bay region. Ongoing restoration, monitoring, and research is needed to restore the watershed’s historical role in the ecosystem. “The creek here is spring-fed and we’re going to be restoring [salmon] habitat and the spawning beds. This has to happen at many, many other dams,” said Lopez.

Waterfall prior to dam removal. Photo: Ian Bornarth, courtesy Sempervirens Fund.

In the same Estuary Summit session, Corrina Gould, chair and spokesperson for the Confederated Villages of Lisjan, spoke of the importance of rebuilding the relationship between salmon and native people.

“We as California people have prayers for the salmon, we remember them as relatives that come to feed and take care of us,” she said. “We have a responsibility to … welcome them home. We can’t do that work because of the culverted rivers and dammed creeks. We have this responsibility, because those salmon don’t have a voice, but we as human beings are supposed to make sure that relationship stays strong. What can we do? We can open up those streams and those waterways.”

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About the author

Elyse writes about wildlife ecology and environmental science for Estuary. Her background as a wildlife biologist often leads her to stories about the joys of scientific discovery and the ways that people interact with, and about, the environment. She currently writes from a floating abode in the San Francisco Bay, where the neighbors occasionally nest on her roof. Some of her writing and photography can be found here.

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