Orange County Branch Newsletter

July 2011

Branch News - June Luncheon Event

June Luncheon Event

San Juan Creek Presentation


This month’s luncheon event was hosted jointly by the OC Branch with the Hydrology & Hydraulics Technical Group at the UCI University Club.  The buffet lunch and presentation was attended by sixty nine on June 21st where our presenter Mr. Phil Jones, P.E. of OC Public Works provided an informative yet entertaining presentation on the San Juan, Trabuco, and Oso Creeks watershed.

We were honored to have Phil, who presented in 2005, return to share with us the latest on this 176 square miles watershed as last winter’s storms showed just how unpredictable Mother Nature can be.  Phil began with some interesting facts on this unique watershed and history that dates back to the 1600’s. Beginning in the Cleveland National Forest, the waters of Trabuco Creek Confluence with San Juan Creek and outlets at Doheny Beach with a time of concentration of 3 hrs 14 min according to the 100-yr study by PACE.  The colorful history of the watershed includes wine, celebrities, a clothesline, and a bear during various times.

With the channel lining failure in 1998 along Trabuco Creek and the another along San Juan Creek  in 2005, and recently the lining failure along Trabuco Creek in December 2010, OC Public Works has been working on a levee protection program since 2005 that consists of driving sheet piles along both channels.  The program consists of eight phases that includes the reach of San Juan Creek from upstream of Stonehill Drive to downstream of the I-5 Freeway, and Trabuco Creek from the confluence with San Juan Creek to 1600 ft upstream of Del Obispo Street.   Phase 1, completed in October 2009 consisted of approximately 4,000 channel feet of steel sheet piles that are 35 ft and 48 ft long that will provide protection to the west side levee segment that was severely damaged by the January 2005 storms  by the “Pineapple Express”.  OC Public works applied for and was awarded a grant for the Phase 1 project receiving $5 Million from the California Department of Water Resources after project completion.

Last fall, just prior to the start of the rainy season, construction of Phases 2 and 3 was completed.  Slated for construction this next fiscal year, Phase 7 will include the segment that was damaged in last winter’s storms.  After all eight phases are completed, the total final cost could be approximately $75M to $95M.  

You can watch Phil’s presentation below: