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: September 26, 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. The fall HORB generally is installed late in September upon the request of the CA Department of Fish and Game and depends upon the current and projected dissolved oxygen levels in the San Joaquin River near Stockton. Yesterday, DFG informally requested the HORB be installed and we expect the formal letter early next week. We’ve notified the barrier contractor and they will begin work about the middle of next week.
Agricultural Barriers (Old River near Tracy [ORT], Middle River [MR], Grant Line Canal [GLC]):
All the ag barriers are fully operating with all culvert flap gate opening and closing with the tides. Early next week three of the nine culvert flap gates at the ORT barrier will be tied open to allow more circulation upstream of the barrier on Old River and improve water quality in that area. We may untie these flap gates later as the HORB is installed if water levels become an issue.
Modeling was not done this week as all the barriers have been operating fully. However, we’ll begin modeling again next week once we tie open three culverts at the ORT barrier and begin installing the HORB. This week actual water levels have been at or above the trigger levels (0.0 feet MSL at both ORT and GLC barriers, 0.3 feet MSL at the MR barrier).
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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