South Delta Program

In the 1960s, DWR began installing a barrier at the head of Old River in the fall to assist salmon migrating up the San Joaquin River to spawn. In the late 1980s, barriers were installed in other south Delta channels to raise water levels and improve circulation for local irrigators. Installation of a spring fish barrier began in 1992 at the same location as the fall barrier to protect young salmon migrating down the San Joaquin River from swimming toward the CVP and SWP water export facilities where they are subject to entrainment. Today, all of these barriers are installed as part of the South Delta Temporary Barriers Program. The barriers are rock structures that contain operable culverts to pass flow upstream or downstream of the barriers as needed.

In the 1980s DWR and the Bureau of Reclamation began formulation of a permanent program, which included four permanent, fully operable barriers to replace the temporary structures, of south Delta improvements.

DWR and Reclamation originally planned for this program to be implemented in advance of the long-term solutions to be developed by the CALFED Bay-Delta Program. However, to avoid any incompatibility between the permanent south Delta program and the long-term CALFED process and to advance other actions proposed by CALFED for early implementation, the permanent south Delta program has been adopted as a part of the CALFED process.

The reformulated program is known as the South Delta Improvements Program (SDIP). It includes the improvements proposed by DWR and Reclamation. However the Clifton Court Forebay’s new intake gate, which would be screened, may be relocated in Old River near Italian Slough. SDIP also includes new fish facilities to increase fish salvage and survival and reduce predation within the forebay, as well as other potential alternatives.

DWR plans to complete the site-specific environmental documentation for the recommended SDIP alternatives in 2001. SDIP, in combination with other CALFED programs, will help ensure that the key objectives of ecosystem restoration, water quality, water supply reliability, and levee integrity will be achieved in the next 7-10 years.