August 15, 2017
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One of the Largest Dam Removals in California History Inches Forward

Matilija Dam in Ojai, California, no longer functions as it was intended, but it has still been a battle to raise the funds necessary to remove the 168ft-high structure that is impeding fish and coastal habitat.

Michelaina Johnson


NESTLED IN THE mountains of the quiet California town of Ojai is Matilija Dam, which has become a poster child of the national dam removal movement. At 168ft high, the dam towers above Matilija Creek. Since the dam’s construction in 1947, an estimated 8 million cubic yards of sediment have clogged Matilija reservoir, rendering it useless for water storage and flood control, while trapping sediment that would have flowed into the Ventura River and then fed Ventura’s coastline nearly 16 miles downstream.

“It doesn’t have any purpose anymore,” said Peter Sheydayi, the design and construction deputy director of the Ventura County Watershed Protection District (VCWPD), the government agency that owns the dam.

Paul Jenkin, an avid surfer with a background in ocean engineering, noticed the city of Ventura’s acute coastal erosion and singled out the removal of Matilija Dam as one of the long-term solutions to addressing the problem. Starting with bumper stickers that read “Give a Dam, Free the Sand, Grow the Beach!” in the mid-1990s, Jenkin started a grassroots campaign to remove Matilija Dam and revive Ventura’s shoreline as well as restore endangered Southern California steelhead trout’s spawning habitat in the Ventura River watershed. If the dam is taken out, it will be one of the largest dam removals in California history.

If the dam is dismantled, the ecological benefits to the Ventura River watershed would be huge. The reservoir has inundated 27 percent of the endangered steelhead’s original spawning habitat in the Ventura River watershed. With the dam gone, more than 31 miles of steelhead spawning habitat would be restored and 116 miles and 154 acres of the Ventura River and its tributaries enhanced. The dam’s removal would also release approximately 4 million cubic yards of sediment, reversing downstream channel degradation and restoring channel bed elevations to roughly pre-dam levels in about 10 years.

Over the past two decades, Jenkin’s effort has gained national traction, with influential environmental groups, government agencies and Patagonia, among others, joining the campaign and propelling the project into the national spotlight. The 2014 documentary DamNation prominently featured Matilija Dam at the end of the film, showing an anti-dam activist painting a pair of scissors cutting the concrete wall – a symbol that has come to represent the dam removal movement.

In 2000, then United States secretary of the interior Bruce Babbitt took out an 8 ton section of the dam with a crane as part of a dam removal demonstration project for the VCWPD – a move that gave the project a lot of publicity but did not lead to deconstruction.

The North Fork of Matilija Creek before the creek flows into the reservoir behind the dam. (Michelaina Johnson)

Since then, no more of the dam has been extracted, but a large contingent of people continue to do the background work necessary to reconnect Matilija Creek with the Pacific Ocean. After years of studies and planning, the dozens of stakeholder groups involved in the dam removal campaign, including American Rivers, the California Coastal Conservancy and California Trout, were hopeful when Congress in 2007 approved funding to remove the dam based on a plan by the Army Corps of Engineers. Funding came to a halt, however, as removal costs escalated.

Due to the lack of momentum from Congress, the stakeholders in Ventura County reconvened to come up with alternatives to the congressionally approved plan. In 2016, technical studies led them to agree on a plan that would cost almost half the price tag of the Corps’ design. At $111 million in today’s dollars, the concept involves boring two holes near the dam’s base to use Matilija Creek’s natural transport capacity to flush out the fine sediment trapped behind the dam during a flood. Ventura County would then be able to take apart the rest of the dam without the danger posed by the sediment stuck behind it.

“In the face of climate change and sea level rise, we really need that sediment down at the coast,” said Hans Cole, the director of environmental campaigns and advocacy for Patagonia and chair of the Matilija Dam Removal Funding Committee.

Thanks to a $3.3 million grant from the California Department of Fish and Wildlife, the project will take a huge leap toward completion of the final design phase for removing the dam. The grant, funded by Proposition 1, will complete the environmental and permitting requirements of the project over the next three years as well as advancing the engineering design for removing the dam.

Recognizing that dismantling the dam will increase the size of floods on the Ventura River and strain downstream infrastructure, Ventura County has generated a list of projects and property acquisitions that must be completed before Matilija Dam is taken out. Sheydayi said that some on-the-ground improvements are planned for the next few years, but they are contingent on funding and study results, as is the case for the dam removal itself.

Last year, the effort received a financial boost of $175,000 from the William and Flora Hewlett Foundation’s Open Rivers Fund, which finances the removal of obsolete dams throughout the American West. The removal of such dams throughout the Pacific Northwest and California has provided models for the VCWPD and the other stakeholders, as they determine which tactic is most applicable for dismantling Matilija Dam.

Sheydayi said that when the Matilija Dam removal was first proposed, there was no precedent for the project. But, two decades later, several high-profile dams across the Pacific Northwest and in California, including the Condit Dam on the White Salmon River in Washington and the San Clemente Dam on the Carmel River in California, have been dismantled, demonstrating what Ventura County should expect in the aftermath of the removal of Matilija Dam.

“What we’re seeing with dam removal is that a river will restore itself quicker than anyone predicted,” said Jenkin.

He is pushing for Matilija Dam to be taken out by 2025, but there is a confluence of factors that have to align to make the removal possible. For instance, the campaign has to cobble together more than $100 million in funding. Then, a rainstorm strong enough to wash out the sediment trapped behind the dam must also coincide with Ojai’s reservoir, Lake Casitas, having enough water to tolerate the temporary shutdown of a local diversion that would normally refill the man-made reservoir.

“One of the exciting things about Matilija is that it could serve as a model for other dam removals across the country,” said Cole. “We really see it as the next step forward in this nationwide effort to free the rivers.”


Originally appeared at newsdeeply.com

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