CONSTRUCTION ON A $2 billion levee project that will effectively protect more than a third of Stocktonians’ homes from flooding kicked off this past Friday. 

Local government officials took part in an April 18 groundbreaking ceremony off March Lane at Tenmile Slough in Brookside to launch the Lower San Joaquin River Improvement Project.

“This project is trying to make sure that we are protecting the next generations of San Joaquin County residents,” said 9th District Rep. Josh Harder to a small crowd of officials and government agencies.

The first phase of the project, slated for completion in late 2026, will see improvements made to just over a mile of the Tenmile Slough levee, which sits directly in the backyard of many homes in the Brookside area of west Stockton, according to a presentation on the project’s overview. About one mile of the levee will be upgraded to have a seepage cutoff wall, which is an added layer of material preventing water seeping through or under the levee.

The entire project includes infrastructure upgrades to nearly 24 miles of levees that is expected to be completed by 2039.

The project is a joint effort of many agencies responsible for maintaining and upgrading levees along the San Joaquin and Calaveras rivers to federal standards, including the U.S. Army Corps of Engineers, California’s Central Valley Flood Protection Board and its Department of Water Resources, and the San Joaquin Area Flood Control Agency (SJAFCA).

A 1960s relic in need of repairs

Glenn Prasad, SJAFCA deputy executive director, told Stocktonia that while the levee was built to protect homes, they’re outdated and pose a potential danger now. 

“These levees were built in the 1960s, and the standards of the time were much different,” Prasad said. “Technically, what’s inside of it in the heart of the levee is not structurally stable.”

Cost share for the project sits at 65% from the federal government, 25% from the state and 10% from local sourcing, according to SJAFCA. In 2023, approximately 94,000 Stockton residents showed support for the project by voting to pay an annual property assessment to help fund a portion of the work. 

The U.S Army Corps of Engineers had what Prasada described to Stocktonia as a no-brainer decision to fund the majority of the project due to its high benefit-cost ratio.

“The benefit-cost ratio on this is seven, meaning for every dollar put in, you get $7 back. That’s the highest in the nation,” he said.

“I want to thank everyone for these improvements, which will reduce the flood risk for over 120,000 residents. This levy is part of a larger system that protects more than $28 billion in damageable property in north and central Stockton.” Supervisor Paul Canepa

In a speech at the groundbreaking event, Board of Supervisors Chair Paul Canepa said the project will benefit a large number of locals.

“I want to thank everyone for these improvements, which will reduce the flood risk for over 120,000 residents,” he said. “This levy is part of a larger system that protects more than $28 billion in damageable property in north and central Stockton.”

Potential construction impacts for those in the area include construction trucks, which may bring noise, dust and vibration, however “best management practices” will attempt to limit inconvenience.

However, local officials ended the groundbreaking event by grabbing a shovel and scooping dirt, representing the slough’s upgrades soon to come.

This story originally appeared in Stocktonia.