It's a project two decades in the making, to re-open a key Bay Area marsh that's been dormant for nearly 100 years.
Within a matter of minutes, a pair of giant excavators cleared away tons of dirt, and breached the levee, allowing tens of thousands of gallons of bay water to rush in.
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"It's a huge day for us," said Paul Detjens, Senior Engineer with the Contra Costa County Flood Control District. "We've lost about 80 to 85 percent of our marshlands surrounding the bay, so this is an opportunity to really bring that type of habitat back."
The breach allows the salt water of Suisun Bay to flow back into the 232 acres Pacheco Marsh, a giant step in restoring not just the marsh, but the lower Walnut Creek watershed.
And it's all part of a larger effort to restore the San Francisco Bay shoreline.
"The environmental benefit is we're creating habitat specifically for the salt marsh harvest mouse," explained Detjens, "and we also have rare birds, like black rails which are actually right around the edge of our site."
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The revitalized marsh is also designed to be resilient to the sea level rise expected with climate change.
Now that there's water back in this marsh for the first time in a century, the expectation is that birds and other species will also follow. And at some point, this will also be a recreation area for people.
#HAPPENINGNOW For the first time in a century, the levee has been breached and water is flowing from San Pablo Bay into Pacheco Marsh, a habitat that will be restored for birds and other species…and eventually trails and recreational area for the public. @JohnMuirLT pic.twitter.com/uv9bZeshEy— Laura Anthony (@LauraAnthony7) October 29, 2021
"To be able to come and enjoy the shoreline, which is otherwise inaccessible for miles in either direction, and to really really emphasize the notion of environmental education for generations to come," said Linus Eukel, Executive Director of the John Muir Land Trust, a key partner in the project.
The plan includes nearly three miles of walking trails and a visitor's center, all set for completion in 2023.