The invasive two-inch wide golden mussel showed up near the Port of Stockton last fall. Since then, it’s spread south, extending to other waterways in the Delta and some in the San Joaquin Valley.
Now, eyes are looking north to Lake Oroville, where the mussels could pose a large threat if they’re introduced.
The reservoir is the second largest in California. It’s part of the state’s system that delivers water through a network of pipes and pumps to more than two-thirds of residents and hundreds of thousands of acres of farmland.
Golden mussels like to stick to hard surfaces — like those pipes and pumps — and that has state officials concerned.
“They're going to grow, they're going to settle out, attach onto the walls, and then begin forming those colonies,” said Tanya Veldhuizen, an environmental program manager with the Department of Water Resources. “They just keep adding layers and layers and mussels until that pipeline is completely blocked.”
"With our infrastructure, none of it was designed with mussels in mind, and so a lot of this pipeline is embedded in concrete. It is inaccessible."- Tanya Veldhuizen, California Department of Water Resources environmental program manager
Golden mussels spread by attaching to boats, but also through larvae, which is microscopic and flows easily through water.
“With our infrastructure, none of it was designed with mussels in mind, and so a lot of this pipeline is embedded in concrete. It is inaccessible,” said Veldhuizen.
If the larvae got into Lake Oroville, Veldhuizen said they could travel downstream, settling and potentially clogging infrastructure throughout the entire water system. That poses a huge challenge for state water officials.
“None of it was designed with mussels in mind, and so a lot of this pipeline is embedded in concrete. It is inaccessible,” Veldhuizen said.
This is the time of year is when mussels start laying eggs, which quickly turn into larvae. Veldhuzen said the situation is urgent.
The department is working on mitigation, including adding new equipment to pumping plants and looking into chemical treatments.
They’ve been conducting boat inspections at some waterways. Checks start at Lake Oroville next week.
