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:   August 25, 2014


Forecasting of water level was performed by the Delta-Operation Section and plots are attached for all three agricultural barriers up to September 08, 2014.  All water levels at the three agricultural barriers seem to be above the threshold during the specified forecasting period.  DWR recently modified the culvert flap gate operation at the Grant Line Canal barrier by having three of the six culverts flap gates tied in the open position in order to help improve water quality in the region; the “Summary of 2014 Temporary Barriers Culvert Operations” listed below shows the change to the Grant Line Canal barrier.  If additional culverts need to be tied open, DWR will provide notification for any changes prior to implementing. Moreover, monitoring of any adverse changes in water level and water quality conditions will be reported and documented.



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


  • The temporary agricultural barrier installation of the Middle River started on March 11, 2014 with the weir section closure by March 17, 2014.  The culvert flap gates have been operating tidally as of April 8, 2014; the weir section at this barrier was raised on June 26, 2014 by one foot to enhance circulation and improve water surface elevation during the high water demand of the irrigation season.


  • The installation of the Old River near Tracy barrier started on March 11, 2014.  The weir section was closed on Thursday, April 3, 2014 and the barrier construction was completed on Tuesday April 8, 2014.  The culvert flap gates have been tidally operated as of April 8, 2014.  The boat tender is on duty but the water hyacinth still blocking the boat ramp making the hauling operation out-of-service.  Please see attached photo.


  • The partial closure of the Grant Line Canal barrier was achieved on Friday March 28, 2014.  Full closure of the weir section occurred on June 3, 2014.  The culvert flap-gates were released to tidal operation on June 25, 2014, but three of the six culverts flap gates were tied open on August 12, 2014 at 2:30 p.m. in order to improve water quality in the area.  The boat tender was on duty.  No water hyacinth was impacting the Grant line Canal barrier at this time as per our latest field inspection.


Notching the Barriers:


On September 15, 2014 the Middle River barrier and the Old River near Tracy barrier will be notched and the opening of the flashboard structure at the Grant Line Canal will be adjusted as required by the regulatory permits to allow passages and attractive flows to the up-migrating fish.


Head of Old River Barrier [HORB]:


The construction on the spring Head of Old River barrier began on Tuesday March 25, 2014.  Closure was achieved on April 08, 2014.  The barrier construction was completed on Friday April 11, 2014.  All 8 slide gates were open during its entire spring operation.  Construction removal of the barrier started on May 28, 2014 and breach of the weir section occurred on Monday June 9, 2014.  The construction removal/demobilization process was completed on Thursday June 25, 2014.


 Fall Head of Old River Barrier:


DWR is still in consultation with the California Department of Fish and Wildlife to reach an agreement regarding the installation of the fall head of Old River barrier.  DWR will send notifications one way or another as soon as an agreement is reached.



Summary of 2014 Temporary Barriers Culvert Operations


Environmental Permits Compliance Reporting:


Staff completed the environmental compliance monitoring on June 26, 2014 when construction was completed on the Middle River barrier raise.  The terms of all environmental permits have been met, and compliance monitoring will continue until and during the barriers’ removal this fall.


Water Levels and Water Quality Notifications:


All three agricultural barriers (Middle River, Grant Line Canal, and Old River near Tracy) are fully closed and the Spring Head of Old River Barrier has been removed.  DWR continues to monitor water levels.



No new modeling was performed since the last modeling results previously attached in our July 24, 2014 update for the period from July 15 to August 5, 2014.  That modeling run showed actual minimum water levels were above target levels at the Middle River, Grant Line Canal, and Old River near Tracy barriers, it also showed that water level should remain that way through the end of the forecast period.  

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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