Monday, July 23, 2012

Major Sand Replenishment Project Coming to the Sloat Area


The Workings of a Dynamic Beach…

A dynamic beach is always in flux.  Sand erodes and accretes (builds up) on a continual basis.  Here is an example: The photo at the top is of Ortega Street from June 2011- midway through incoming tide. The photo on the bottom is the same exact spot, at approximately the same tide, but one year later...When it comes to erosion threats to the Great Highway, Sloat is unique. Accretion processes have failed to regenerate the beach.

Dear Surfriders and Friends,

At the sand management meeting the other night, we got a look at the details of the new sand replenishment project being coordinated by NPS, SFPUC and SFDPW. It is scheduled to start in August; and will deliver significant quantities of sand to the south of Sloat area. The material will be excavated from the beach in front of the O'Shaughnessy seawall (Stairwells 1-21). The measure should help to alleviate the problem of sand accumulation on the road and parking lots at the north end of Ocean Beach. The preliminary cost estimate approximately $700,000. See NPS website for more info. There will be short term closures of some of the parking areas to make this happen. The south bound lanes of the Great Highway will also need to be closed during construction. The project is due to be completed by early September.

The end result will be two separate large sand dunes on the beach, one covering the area just south of 1st parking lot and the other at the south end of 2nd lot. The dunes will be approximately 30-40 in width, effectively burying any rock or rubble in the area where they are placed.

Surfrider generally supports this measure as a temporary measure to improve access to the beach. However, it should be emphasized that this is not the sustainable long term solution forged by the Ocean Beach Master Plan. Most of this sand is projected to wash away at some point. That being said, the project will improve access, aesthetics, and should help to some degree in avoiding new erosion emergencies that bring rock armor onto the beach.

Our chapter continues to call for the removal of rubble and concrete debris already littering the beach. Previous posts have illustrated the point that much of this debris has drifted away from the bluff and is poised to enter the surf zone.  We hope to see some kind of work on this issue before the sand is placed. By removing; or at least re-aligning the debris back onto the bluff, more beach area will be available when the sand erodes. This would help delay wave contact with the rock, thus forestalling the erosive effects of wave scour and backwash.

Thanks for checking in. Please do stay tuned for further developments and information!



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