The following report on the Temporary Barriers Project is for your information and action, as appropriate.  This report will be transmitted whenever changes occur to the operation of the barriers, and as a result of modeling and/or field monitoring of water levels in the south Delta.

STATUS AS OF:  June 15 , 2007

Head of Old River Barrier (HORB):

The Spring HOR barrier has been completely removed.  The HOR barrier will be re-installed in the fall upon request by DFG.

Agricultural Barriers (Old River near Tracy [ORT], Middle River [MR], Grant Line Canal [GLC]):

All agricultural barriers are in place and operating normally.  Use of EWA assets over the last few weeks to keep exports low have required the culvert flap gates to be tied open in accordance with our permits, but EWA assets now are no longer being used.  Today, the culvert flap gates were untied to allow normal one-way tidal flow.  Project exports are expected to significantly increase beginning Sunday, June 17, and this action to untie the flap gates is necessary to protect south Delta water levels for agricultural irrigation.



Modeling was completed today based upon tidal operation of the flap gates beginning June 15, 2007 and the results attached.  Low-low water levels are projected to remain above the level of concern at the ORT, and GLC monitoring stations (0.0 feet MSL) and the level of concern at the MR station (0.3 feet MSL).


Modeling Outputs:

Middle River at Howard Road Bridge
Doughty Cut above GLC Barrier
Old River near Tracy Road Bridge


These weekly updates are also available for your information on our NEW!!! website:

Please delete your old “favorite” for the Temporary Barriers Project and add this new site!

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Mark A. Holderman, P.E.
Chief, Temporary Barriers Project and Lower San Joaquin
Bay-Delta Office

California Department of Water Resources
1416 9th St., P.O. Box 942836
Sacramento, CA 94236-0001

Phone: (916) 653-7429  FAX: (916) 653-6077
Cell/Pager: (916) 601-6036 E-Mail: