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:  April 9, 2009

Welcome to the beginning of the 2009 Temporary Barriers Project season!

Head of Old River Barrier (HORB):

The spring Head of Old River rock barrier will not be installed this season.  Instead a Non-Physical Barrier (NPB) or “bubble barrier” is being installed.  Installation began April 7.  This experimental barrier—placed near the channel bottom and extending across the entrance to Old River—will use a combination of bubbles, lights, and sound to guide outmigrating Chinook salmon smolts away from Old River to continue their migration down the San Joaquin River.  Underwater receivers will be installed to detect tagged smolts during the upcoming VAMP experiment fish releases to study the effectiveness of this NPB.  The NPB will be removed at the end of May after the VAMP experiment ends.

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

Ag barriers are planned for installation in early May in accordance with past schedules.  However, we are working closely with the U.S. Fish and Wildlife Agency to obtain a needed biological opinion for the construction impacts before we begin work.



Modeling will begin once the ag barriers are installed.


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: