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 16, 2012

As stipulated by court order, the Head of Old River, Middle River, and Old River Tracy Temporary Rock Barriers were installed approximately two weeks early.  The early closure of the Head of Old River Rock barrier is intended to benefit out-migrating juvenile Chinook salmon and steelhead.

Head of Old River (HOR) Barrier:

Construction of the Head of Old River barrier began on March 15, 2012. Barrier closure and operation were achieved at noon on April 1, all eight slide-gate culverts are in open position. Crews completed construction the clay weir section of the barrier on April 11, 2012. 


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

Construction of the Middle River barrier began on March 12 and closure was obtained on March 16.  All flap gates are tidally operated.

Construction of the Old River near Tracy barrier began on March 15 and closure and operation was achieved at 5:00 p.m. on March 31. All nine flap-gate culverts are tidally operated.  The boat ramp and portage is in full operation as of Wednesday, April 4. Demobilizing and site cleanup was completed on Friday April 6.

The construction of the Grant Line Canal barrier is underway. Crew will complete about 2/3 of the barrier and leave the center weir portion open until early June.  Operation of the barrier will begin with approval from USFWS after delta smelt concerns have passed.


Water Levels/Water Quality/Sound Monitoring Problem Notifications:
In compliance with the 401 Certification, staff performs twice daily turbidity and settable solids water sampling during construction.  Sampling continues at the Grant Line Canal. No violation of the conditions have been observed.


Modeling results are attached and forecasted minimum water levels are above target levels at Middle River at Howard Road (MHR) and Old River at Tracy Boulevard (OLD) stations, but below target levels at Doughty Cut (DGL) station. 
Water levels for the forecast period are as follows:

MHR – Actual water levels are slightly above the models forecast. 
OLD – Actual water levels have ranged to as much as 0.5 ft above the model forecast water levels.
DGL – Actual water levels are following the models forecast water levels.

TBP staff continues to monitor water levels very closely, and water levels at DGL reached a minimum stage on 4/16/12 that was slightly below the target elevation.

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!

Jacob McQuirk, 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) 653-9883  FAX: (916) 653-6077
Cell: (916) 425-6857 E-Mail: