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:  August 1 , 2008


Head of Old River Barrier (HORB):

The spring HOR barrier work will not be installed this year due to a court decision by US District Court Judge Wanger that prohibited the installation of the spring barrier to increase protections for delta smelt.  This is an interim decision that effects the 2008 season only.  The fall HORB is not effected.

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

All the agricultural barriers are operating normally, with their culvert flap gates opening and closing tidally.  However, three culverts are tied open on the ORT barrier for water quality purposes.  Today an order was given the Delta Field Division to tie open three more culverts for a total of six.  Completion of the order hasn’t been confirmed yet.  These additional open culverts will help improve circulation particularly while a spring tide is occurring and without adversely impacting water levels.  Sometime mid-next week we’ll order a change back to three open culverts while the neap tide approaches.  This will be our normal operation as we move from spring to neap tides as long as they don’t adversely cause water levels to drop below trigger levels.  


Modeling has not been completed this week but will be sent separately early next week when it becomes available. Modeling finished from last week is attached and shows that actuals and forecasts are good for water levels.  Water levels have been well above the trigger levels (0.0 feet MSL at both ORT and GLC barriers, 0.3 feet MSL at the MR barrier) and should remain above through next week.


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


If you know of anyone else that should be receiving this update, please let me know by email, and I'll add them to the mailing list.  Thanks!


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: