Southport Early Implementation Project

A cornerstone project for cbec, spanning multiple years, and with various project team configurations, this West Sacramento Area Flood Control Agency (WSAFCA) project’s goal is to set back parts of the Sacramento River levee through West Sacramento. This plan will provide 200-year level of flood protection, valuable ecological function, and high recreational value on the restored floodplain. The project has completed design and is now under construction.

cbec provided geomorphic and hydrodynamic/ morphologic modeling services, as well as ecological habitat design for aquatic and terrestrial species to the project. Our role was to analyze hydraulic and geomorphic conditions at the site, assess the potential for levee and channel erosion / deposition, and estimate sedimentation impacts for the preferred design alternative. To accomplish this, we used a combination of field geomorphic interpretation and two-dimensional hydraulic and sediment transport modeling. For this project, we developed a MIKE-21C hydrodynamic and sediment transport model for a 12-mile reach of the Sacramento River. Using the model and the geomorphic assessments, cbec established how the sites evolved historically, which informed the design of the setback levees relative to the sediment transport regime, and developed habitat restoration concepts to improve floodplain ecosystem function. Our findings enabled the project team to design flood management solutions that are geomorphically stable while restoring the floodplain’s ecological function.

The project is currently going through construction and cbec staff are providing construction support and monitoring water quality in the Sacramento River during construction.

Details

River/Watershed: Sacramento River
Project: 10-1043, 11-1003, 11-1013, 12-1001, 17-1024, 17-1026