Golden Mussel Invasion Threatens California's Water and Agriculture

The invasive species is clogging pipes, damaging boats, and posing a major challenge for farmers and water districts across the state.

Jan. 28, 2026 at 8:15pm

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The golden mussel, an invasive species, has spread rapidly throughout California, causing major problems for the state's water systems and agricultural industry. The mussels are clogging pipes, damaging boats, and threatening water supplies, particularly in the Central Valley where farmers rely on the water for their crops. Water districts are facing costly repairs, while boaters have had to spend thousands to maintain their vessels. Experts warn that more lake and reservoir closures are likely as officials struggle to find ways to stop the golden mussel's spread.

Why it matters

The golden mussel invasion poses a significant threat to California's critical water infrastructure and agricultural industry. As the mussels spread, they can restrict water flow, damage equipment, and disrupt access to vital water sources. This could have devastating consequences for farmers, water districts, and communities that depend on reliable water supplies, especially during periods of drought.

The details

The golden mussels have been detected in key water sources like the San Luis Reservoir and Friant-Kern Canal in the Central Valley. They reproduce quickly and form dense colonies that are difficult to remove. Farmers are particularly at risk, as the mussels can build up in pumps over the winter and completely restrict water flow when the pumps are turned on in the spring. Beyond agriculture, the mussels also threaten urban areas by potentially clogging pipes used for flood control. Replacing infrastructure affected by the golden mussels can cost water districts tens of thousands of dollars.

  • The golden mussel invasion has been an ongoing issue in California, with sightings heavily concentrated in the Northern Central Valley and detections stretching throughout the valley and into Southern California.
  • A reservoir in the East Bay remains closed to boats due to the golden mussel spread, and experts warn that more closures are likely as officials work to find solutions.

The players

Andrew Genasci

The executive director of the San Joaquin Farm Bureau, who has been closely monitoring the golden mussel invasion and its impact on the region's agriculture and water systems.

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What they’re saying

“These little guys are incredibly resilient and tough to kill,”

— Andrew Genasci, San Joaquin Farm Bureau executive director (kmph.com)

“What happens when we're in the middle of a drought, or it dries up, and you need that water to try and keep your crops alive, and all of a sudden, I've got nothing out of my pump?”

— Andrew Genasci, San Joaquin Farm Bureau executive director (kmph.com)

“You could have these pipes plugged, you go to use them, you don't know there's an issue until you try and turn them on, and all of a sudden you're not able to remove flood water. So you're looking at potential damage for urban areas as well as rural areas,”

— Andrew Genasci, San Joaquin Farm Bureau executive director (kmph.com)

“Unfortunately, you're going to see probably quite a few more closures while we get a handle on, you know, the best ways to prevent the spread, the best ways to kill the little guys. So that they can't get into all of your infrastructure at these lakes and reservoirs,”

— Andrew Genasci, San Joaquin Farm Bureau executive director (kmph.com)

What’s next

Experts and officials are working to find effective ways to prevent the further spread of the golden mussels and remove them from affected water systems and infrastructure. This will likely involve a combination of monitoring, containment, and eradication efforts to protect California's vital water resources and agricultural industry.

The takeaway

The golden mussel invasion is a significant and growing challenge for California, threatening the state's water systems, agricultural productivity, and overall economic well-being. Addressing this issue will require a coordinated, multi-pronged approach by policymakers, water managers, and the agricultural community to safeguard the state's critical water infrastructure and food production capabilities.