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 8, 2016

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

The installation of the Middle River barrier started on March 2, 2016 and the weir was closed on March 9, 2016 at 11:30 am.  Construction completed on March 10, 2016.  All flap gates are tidally operating as of 3:40 PM on April 1, 2016.
The installation of the Old River at Tracy barrier started on March 3, 2016.  Construction crew closed the barrier on Friday March 25, 2016.  On April 1, 2016 at 2:20 PM the flap gates were released and are functioning with the tide.
The construction crew started working on the Grant Line Canal barrier on Monday March 28, 2016, crew is still working on the installation of the barrier’s abutment located at the north levee.  Construction activities will continue until Wednesday or Thursday of next week when partial closure of the GLC barrier will be achieved.  Full closure will take place when the Delta smelt clears the area and when permission is granted from USFWS typically in late May or early June.

Head of Old River Barrier [HORB]:

The construction on the Spring Head of Old River barrier started on March 10, 2016 at 7am.  The construction crew closed the head of Old River barrier on April 1, 2016 at 12:30 PM.  All slide gates are placed in the open position in compliance with the environmental permits.

Environmental Permits Compliance Reporting:

Environmental staff conducted pre-construction surveys as required by State and Federal permits and Biological Opinions. 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.

Water Levels and Water Quality Notifications:

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


Thanks to Siqing of the Delta Compliance and Modeling Section, computer modeling for water level was performed. A copy of the modeling results is attached for the modeling period from 04-06-16 through 04-25-16.  Water level at the Middle River and the Old River near Tracy sites were at the threshold line earlier in the week but now and for the extended modeling period, water level is above the threshold line.  At the Grant Line Canal site water level earlier in the week dipped below the threshold line but later made a recovery and now and for the extended forecast period, the water level is above the concern level.

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

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

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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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