Executive Director's Column Fall 2003

San Dieguito River Mouth Controversy

By Dick Bobertz, Executive Director
San Dieguito River Park Joint Powers Authority

There is an ongoing controversy between Sandy Lane homeowners and the San Dieguito River Park concerning the relationship between opening the San Dieguito River mouth to the ocean and the amount of sand available to maintain Del Mar Beaches. The Sandy Lane homeowners have residences located on the beach on the south side of the river that are currently in jeopardy from winter storm wave action and river mouth flooding. That is because the houses were built in an area of known natural hazard. It is understandable that they would be concerned because their homes are at risk now and the long-term prognosis for beaches all along the California Coast is poor. The natural sand supply that used to nourish beaches after erosion from winter storms has been intercepted by flood control projects and dams built in the 1900’s. It is estimated that the total cumulative deficit of sand yield to our San Diego County beaches as a consequence of damming of rivers between Dana Point and La Jolla is 27 million cubic yards.

So, it is fair and reasonable to question if the proposed river mouth opening could have any effect on the limited sand now available to maintain the adjacent Del Mar Beach. But it is not fair or reasonable to mislead the public about credible information on the record that does not happen to support a particular assertion. The Sandy Lane homeowners have established a tax-exempt organization called “Save the Beach” which has been flooding the Del Mar area with misleading information designed to alarm the public (and solicit contributions). Don’t take my word for it that their information is misleading; you decide. Here are two examples:

The “Save the Beach” literature and website consistently try to cause alarm by reporting “The basins would be kept permanently open to the ocean through a 130-foot wide, 8 foot deep, channel dredged through the heart of Del Mar beach.” Using a handout distributed at a recent community group meeting a “Save the Beach” representative attacked a Southern California Edison statement that the permanent channel at the river mouth would be only 2 or 3 feet deep as an “Edison Distortion” and cited a page in the Environmental Impact Report as proof of their 8 foot depth assertion. What does that EIR page actually say about the river mouth depth? It says, “The design inlet channel depth east of the inlet sill would be about 3.3 feet below MSL (about –3 feet NGVD) across most of the inlet width. This is equivalent to water column depths ranging from about 1.4 to 3 feet under MSL conditions.”(p.4.10-1). Where do they get the 8-foot depth assertion? Well, the next sentence in the EIR is “Extreme maximum high tides (e.g., those that occur perhaps once in 10 years) could result in even deeper water (e.g., as high as 8 feet) in the inlet for short periods of time.”

“Save the Beach” has also tried to convince the public that other scientists disagree with the scientific studies used to design the project. Their literature asserts: "...evidence was uncovered that all of Edison's scientific experts unanimously agreed that the models used by Edison to predict beach impacts were unreliable, that "(s)ignificant and wholly unforecasted damage" to Del Mar beaches could occur ...” That quote was selectively edited from an April 21, 1998 report from Professor Ashish J. Mehta. The actual sentence he wrote was "Significant and wholly unforecasted damage to sea defenses have been reported along the famous beaches of Rio de Janeiro." His report and the other reports referenced in "Save The Beach" literature was directed at the necessity of monitoring in order to keep the river mouth open. That suggested monitoring was subsequently adopted as part of the project. All the scientific peer review reports complemented the analysis done for the project.

The only scientist to comment negatively on the river mouth opening, Dr. Gregory Stone, has been dismissed by the California Coastal Commission with the finding, “Therefore, the Commission finds that the conclusions in the Stone report are not supported by the facts, and concludes that mechanical opening of the San Dieguito Lagoon inlet should not result in increased erosion to the beach in front of Sandy Lane properties.”

Other responsible government and environmental organizations concerned with beach erosion have reviewed the facts and weighed in on the issue. The San Diego Bay Council, a coalition of environmental organizations adopted a Joint Statement of Support for the San Dieguito Wetlands Restoration Project last May. The coalition includes the Surfrider Foundation, the San Diego Audubon Society, the San Diego Chapter of the Sierra Club, the San Diego Baykeeper, and the Environmental Health Coalition. The California Coastal Coalition (CalCoast), a non-profit advocacy group comprised of 35 coastal cities; seven counties; AMBAG, BEACON, SANDAG and SCAG; along with business associations and allied groups committed to restoring California's shoreline through sand replenishment, increasing the flow of natural sediment, wetlands recovery and improved water quality joined in signing the Joint Statement of Support..
In addition, the City Councils of Del Mar and Solana Beach both adopted Resolutions of Support for the project and recently, the Shoreline Preservation Committee of SANDAG heard presentations from both sides of the issue and directed their staff to prepare a letter of support for the San Dieguito Wetlands Restoration Project.

Please educate yourselves by examining representations from both sides of the controversy. And if you hear something that concerns you, don’t believe it until you read the source material for yourself. A good place to start is the recently published paper; “Effect of Small Southern California Lagoon Entrance on Adjacent Beach” based on long-term research of the Del Mar Beach and San Dieguito River mouth openings by Dr. Hany Elwany (ESTUARIES, Vol. 26, No. 2, June 2003). The beach monitoring done by Dr. Elwany establishes that there is no impact to Del Mar Beaches resulting from river mouth openings. The full paper is also available on the San Dieguito River Park web site www.sdrp.org.

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