Project Status - First Increment of Construction - TS30L (Tenmile Slough)

The dryland levee along Ten Mile Slough is the first reach of design and construction (TS_30_L). Work includes improving approximately 1 mile of levee by installing a seepage cutoff wall, re-grading the levee prism to a more stable condition, and installing rock slope protection to prevent erosion.

Levee degrade and construction will begin in mid-April 2025 and be completed by October 2026. Vegetation removal in preparation for construction will be conducted October 17 - November 1, 2024. Property owners living next to or near the Tenmile Slough levee in Brookside – especially in the vicinity of Rockwood and Vintage Circles – will notice increased traffic on the levee crown between the hours of 8 a.m. and 5p.m. during the work period. Please be cautious of project-related traffic and stay out of restricted areas.

Draft Supplemental Environmental Impact Report
Draft Supplemental Environmental Assessment
Final Supplemental Environmental Impact Report
Certification of the Final Supplemental Environmental Impact Report (Attachment A)

Key Construction Milestones:

Project History

In 2009, SJAFCA partnered with the US Army Corps of Engineers (Corps) and the California Central Valley Flood Protection Board (CVFPB) to study and evaluate ways to improve the region’s level of flood protection. The partnership resulted in the Congressionally-authorized Lower San Joaquin River Feasibility Study, Phase I.

After nine years and $9.1 million invested in the study process, a proposed project was identified that offers an estimated 84 percent reduction in expected annual property damage, while reducing flood risk for 262 critical infrastructure sites, 12 of which are considered essential to life safety. The total estimated cost for the project is $1.39 billion. (Project Overview)

A Chief’s Report in support of the project, formally known as the Lower San Joaquin River Project, was signed on July 31, 2018. Congress formally authorized the project in the America’s Water Infrastructure Act (AWIA). AWIA was signed into law by President Trump on October 23, 2018.

The Lower San Joaquin River Project includes work within north and central Stockton (map on left). It will be implemented in seven increments (map on right).

Final Integrated Interim Feasibility Report/Environmental Impact Report/Environmental Impact Statement

A second phase of the study is ongoing, to include the feasibility evaluation of the Mossdale Tract area. More information on the Lower San Joaquin River Project can be found at USACE, Sacramento District’s website: https://www.spk.usace.army.mil/lower_sj_river/