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 15, 2011
Head of Old River (HOR) Barrier:
The planned spring Head of Old River non-physical barrier was not installed this season due to high flows in the San Joaquin River as a result of late season storm activity and associated heavy snow pack. High velocity flows posed excessively dangerous conditions for divers which ruled out the possibility of installing the necessary equipment on the channel bottom. Fish studies at the HOR have been re-structured to evaluate predatory fish behavior in the absence of a non-physical barrier. In support of this analysis, the Fisheries Foundation captured and tagged predators in the HOR vicinity. The movement of VAMP and 6-yr study releases of tagged salmon smolts and steelhead were tracked in 2 dimensions to evaluate behavior in absence of the NPB. The final fish release for this study was completed on June 18, 2011. All equipment was removed on June 23, 2011.
Agricultural Barriers (Old River near Tracy [ORT], Middle River [MR], Grant Line Canal [GLC]):
Installation of the Old River at Tracy (ORT) barrier started on May 27, 2011 and closure was achieved on June 10, 2011. Site cleanup was completed on June 15th.
Middle River (MR) barrier construction started on June 1, 2011 and was closed Monday June 6, 2011. All culvert flap gates at both barriers are tied open. Installation of the ORT and MR barriers will accommodate on-going fish monitoring studies and support water levels for south Delta diverters. The fish monitoring studies are required by the 2008 National Marine Fisheries Service (NMFS) biological opinion to: 1) examine the movements and survival of listed fish through the channels of the South Delta and ; 2) examine predation effects associated with the TBP.
Installation of the Grantline Canal (GLC) barrier started on Friday June 10, 2011 and included re-construction of the south abutment and culvert structures which were removed at the end of the 2010 season. The Grantline Canal culverts had reached the end of their service life and required replacement to provide on-going barrier effectiveness. The gravel pad for the new culvert structures and all six culverts were in-place on June 24, 2011. Minor settlement of the culvert structures required removal and re-installation of the culverts which was completed on June 29, 2011. Rock backfill which covers the culvert structures was completed on June 30, 2011. Closure of the Grantline Canal barrier was nearly completed on July 14; however, high river flows caused erosion and damaged the existing flashboard structure near the south levee. To relieve pressure on the barrier and prevent scour, larger rocks were placed at the southern barrier abutment and the weir was lowered. Closure of the Grantline barrier is not currently possible, and work will resume once the flow has subsided.
Water Levels/Water Quality Problem Notifications:
In compliance with the 401 Certification, staff performs turbidity and settable solids sampling during in-water construction. No violations have been observed. Bi-weekly water sampling results are sent to the Central Valley Regional Water Quality Board, and the latest results collected during Grantline Canal barrier construction were submitted on July 13, 2011.
Modeling results are attached and water levels are well above target levels at all 3 sites. Minimum water levels for the forecast period occur on July 22, 2011 and are as follows: +0.7 feet above the target level of 0.3 ft in Middle River at Howard Road (Station MHR); +2.1 feet above the target level of 0.0 ft in Old River at Tracy Blvd (Station OLD), and; +2.5 feet above the target level of 0.0 ft in Grantline Canal at Doughty Cut (Station DGL). Actual water surface elevations in Grantline Canal and Old River may significantly depart from forecasts depending on continued Grantline Canal barrier construction but should remain well above target elevations.
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Jacob McQuirk, P.E.
Chief, Temporary Barriers Project and Lower San Joaquin
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: firstname.lastname@example.org