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:   July 3, 2015


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

The installation of the Old River near Tracy barrier started on March 16, 2015. The culvert frames have been backfilled, the underwater boat ramps are completed and the boat docks are in-placed. Closure was achieved on April 3, 2015. All flap gates are tidally operating. The boat tender is on-site.

The installation of the Middle River barrier started Friday March 27, 2015 and the weir was closed on March 30, 2015 . All flap gates are operating with the tide. The Middle River barrier's crest was raised by one foot on June 4, 2015 to help raising water level and circulation for the farmers upstream of the barrier.

The construction of the Grant Line Canal barrier started on March 30, 2015. Partial closure of the barrier was achieved on April 17, 2015. Work on the full closure of the Grant Line Canal barrier started on June 9, 2015. Diving was performed on June 12, 2015 and the closure of the Grant Line Canal barrier was achieved on, June 19, 2015. The culvert flap gates are operating tidally. The boat ramp tender started on June 19, 2015.

Head of Old River Barrier [HORB]:

The construction on the spring Head of Old River barrier started on March 16, 2015. The closure was achieved on April 3, 2015. Construction crews placed concrete mats and installed the clay plug for the weir. All 8 culvert slide gates were placed in the open position.

The removal operation of the head of Old River barrier Started on May 27, 2015; breach was achieved on June 2, 2015 and the completion of the removal of the HOR barrier was achieved by June 8, 2015, however, one frame remains on site as there was a family for Barn Swallows nesting in the frame. They have fledged and the frame were removed on June 23, 2015.

The Emergency Drought Barrier [EDB]:

The Emergency Drought Barrier was closed on May 28, 2015. Dressing the upstream slopes and downstream slopes were completed; compaction work was also completed. The completion of the rock placement was achieved by Friday June 12, 2015. The final inspection was performed on Tuesday June 23, 2015.

Environmental Permits Compliance Reporting:

Environmental staff conducted pre-construction surveys as required by State and Federal permits and Biological Opinions. An Environmental Tailgate Session was held at the Old River Tracy Barrier site to inform construction staff of the permit requirements, to give a general overview of sensitive species found at or near the construction sites and to instruct personnel on proper procedures to follow when sensitive species are encountered on the construction site. Additionally, an Environmental Compliance Monitor is on-site for all construction work, an approved Swainson's Hawk and nesting raptor monitor is conducting regular observations of nesting and territory sites. A water quality monitoring and sampling for settleable solids and turbidity was conducted during the installation of the barriers and it will continue for the reminder of the operation period of the barriers. Exceedance to the water quality threshold has been violated during the installation of the Old River near Tracy barrier resulting in stopping work and waiting for the turbidity measurement to drop within limits. Negotiation with the Control Board took place and an agreement was reached to increase the turbidity threshold from 15 NTU to 150 NTU during the installation and removal operations of the barrier.

Water Levels and Water Quality Notifications:

No exceedance of the water quality turbidity measurements were observed. DWR will continue to monitor the water quality and water levels before, during and after the installation of the temporary barriers.


Computer modeling for water level was performed by Reza of the Delta Compliance and Modeling Section. The modeling period spanned from June 30, 2015 through July 20, 2015. Forecasted water levels are above the specified threshold in Middle River, Old River near Tracy and in Doughty Cut. Please note that the closure of the drought barrier was taken into consideration and it was part of the modeling assumptions. A copy of the modeling results is attached.

Real-time south Delta water level data is available on CDEC at the URL below: 

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Thank you!
Jacob McQuirk, P.E.
DWR|Bay-Delta Office
Temporary Barriers and Lower San Joaquin
1416 9th St., Room 215-23
Sacramento, CA 95814
office:   916-653-9883
Fax:      916-653-6077


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