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 29, 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; the weir was closed on March 9, 2016 and the construction was completed on March 10, 2016.  All flap gates are tidally operating as of April 1, 2016.
The installation of the Old River near Tracy barrier started on March 3, 2016; the construction crew closed the barrier on Friday March 25, 2016.  The flap gates were released to tidal operation on April 1, 2016.
The construction crew started working on the Grant Line Canal barrier on Monday March 28, 2016; the in-water work started on March 30, 2016 with partial closure accomplished by April 14, 2016.  Full closure of the barrier is anticipated in late May or in early June when the Delta smelt clears the area.

Head of Old River Barrier [HORB]:

The construction on the Spring Head of Old River barrier started on March 10, 2016 with closure achieved by April 1, 2016.  All slide gates are placed in the open position in compliance with the Biological Opinions.

Environmental Permits Compliance Reporting:

Environmental staff conducted the pre-construction surveys as required by the State and Federal permits and by the Biological Opinions. Water quality monitoring and sampling for settleable solids and turbidity were conducted during the installation of the barriers and will continue for the reminder of the operation period of the barriers.

Water Levels and Water Quality Notifications:

No exceedance were observed of the water quality turbidity measurements during the installation of the MR, ORT, GLC partial closure, and the HORB.  DWR will routinely monitor the water quality parameters and the water levels during the operation of all barriers.


Thanks to Reza of the Delta Compliance and Modeling Section, computer modeling was performed. A copy of the modeling results is attached for the modeling period from 04-26-16 through 05-16-16.  Water level at Middle River was above the concern level for the modeling duration; the Old River near Tracy site was at the concern line early in the simulation period and also towards the end.  Lastly, the water level at the Grant Line Canal site was  a tad below the threshold line early in the simulation period and also towards the end of the modeling period.  DWR will continue to closely monitor the water level at the Grant Line Canal site and also at the Old River near Tracy location.

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:

Users can now subscribe or unsubscribe to the list by clicking the link below:

Alternatively you can contact me, and I can make additions or removals to the mailing list.

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


To unsubscribe from the DWR_TBPUPDATE list, click the following link: