In order to correct misleading information about the cause of the bacteria in Malibu Lagoon, it is important to understand that that no study has ever directly implicated failing septic systems both commercial or from the Malibu Colony as the source of bacteria. Also, attention to the de-watering plan for the Malibu Lagoon construction project, as it stands, has serious flaws.
In 1992, Mark Gold of Heal the Bay, and a group of researchers, found evidence of Human Enterovirus in Malibu Lagoon but could not determine the source. Researchers then concluded the bacteria could be from illegal campers, diapers, or something other than Malibu Colony septic systems.
Even though Gold’s group did their study when the lagoon berm was closed and the lagoon level was at its highest, they were unable to make the link with Colony septic systems and groundwater feeding the lagoon.
URS Greiner Woodward and Clyde, a company that provides engineering, technical and construction services for both public agencies and private sector companies, conducted two seasons of studies in a joint Malibu and Regional Water Board project, using tracers inserted into commercial toilets to track bacteria and found no direct link (1999 & 2000).
The Risk Assessment Study (2004) tracked groundwater for over a year and found no direct link between bacteria in the creek and lagoon to septic systems, but out of an abundance of caution, suggested that old septic systems near the creek and lagoon and at the Colony should be replaced with newer septic systems that remove bacteria and reduce nutrients, in addition to recommending additional bacteria source-identification research.
Interestingly, monitoring efforts in the past found high bacteria levels in some monitoring wells near the creek or lagoon, and wrongly concluded it was from septic systems.
Water in Malibu Lagoon does have high concentrations of bacteria. One possible source of bacteria to the lagoon that has been suggested is interaction of creek water with bottom sediments containing fecal material from birds. However, Lawrence Berkeley Labs completed DNA analyses of the bacteria in the lagoon and offshore waters and concluded the bacteria is not from humans, pinnepeds or birds. The best available science concludes that regenerative bacteria natural to a lagoon system like Malibu is the source.
This sort of DNA analysis was not even possible five years ago. Warm summer water temperatures and the eutrophic conditions (characterized by an abundant accumulation of nutrients that support a dense growth of algae and other organisms, the decay of which depletes the shallow waters of oxygen in summer) within the lagoon enhance survival, and may potentially allow regrowth of bacteria in water and sediments within the lagoon.
The U.S. Geological Survey (USGS) collected more than 450 samples from the area, that included around the clock access to Colony toilets. No human fecal bacteria were found in the ground water, even when the creek, lagoon and beach water samples exceeded bacteria standards for marine waters. Not surprisingly, DNA and microarray data of bacteria in groundwater were more similar to natural bacterial in the creek and lagoon.
Also, the USGS demonstrated that bacteria do move from the lagoon to Surfrider Beach, even when the berm is closed. The Environmental Protection Agency does not believe bacteria from these natural sources pose the same health risk as human fecal bacteria.
As to the de-watering plan, questions remain regarding the details of the dewatering permit (issued in 2008): is disinfection possible at the required rate of discharge? Where exactly will the water be discharged: dry sand, wet sand, or beyond the surf zone? Are there adequate daily monitoring requirements that ensure health hazards are not created? If hazards are created, is there a public-notice program proposed?
A number of scientists have proved that Methicillin-resistant Staphylococcus Aureus (MRSA)--a contagious and hard to control form of staph--as well as fungus and other bacteria are shed from beachgoers and attach to the dry and wet sand. Current science shows that if these bacteria are disturbed, they dislodge from the sand particles and move into the surf zone.
Current scientific results show that Staph and MRSA in the beach sand and bacteria in the kelp racks could pose a public health risk (National Oceanic and Atmospheric Administration study poster www.malibucity.org). This is the best available science and is not being addressed in the de-watering permit from 2008.
The existing de-watering permit does not describe the discharge location, and the current monitoring plan only requires testing as the water leaves the discharge pipe, but not after it hits the sand or surf zone.
The potential hazards of this incomplete approach cannot be ignored.
