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: May 16, 2008
Head of Old River Barrier (HORB):
The spring HOR barrier work will not be installed this year due to a court decision by US District Court Judge Wanger that prohibited the installation of the spring barrier to increase protections for delta smelt. This is an interim decision that effects the 2008 season only. The fall HORB is not effected.
Agricultural Barriers (Old River near Tracy [ORT], Middle River [MR], Grant Line Canal [GLC]):
Work began May 12 at the DMC barrier. Closure of this barrier is expected by June 4, 2008. The Middle River barrier construction will begin on May 16 and should be completed by May 21. Crews will begin construction of the Grant Line Canal north abutment (boat ramp) on May 15, with full closure determined after late May depending on water levels and delta smelt issues. All flap gates on the barriers will be tied open until after the Vernalis Adaptive Management Plan experiment is concluded in accordance with the Wanger decision.
Modeling will begin next week with the forecast of water levels looking at the week of May 19 and the following week. This will give us an indication of whether water levels will be adequate and whether the GLC barrier needs to be closed late in May or early June.
Fishery agencies and DWR will be closely monitoring conditions for Delta smelt which might effect operations of the barriers during May/June. Changes in flap-gate operations on the culverts, delaying filling of the GLC center section, removal of the barriers, and changes to SWP/CVP export operations are all possible actions that could be taken to protect smelt if necessary.
These weekly updates are also available for your information on our website:
If you know of anyone else that should be receiving this update, please let me know by email, and I'll add them to the mailing list. Thanks!
Mark A. Holderman, P.E.
Chief, Temporary Barriers Project and
California Department of Water Resources
Phone: (916) 653-7429 FAX: (916) 653-6077
Cell/Pager: (916) 601-6036 E-Mail: email@example.com