Study proves Mission Bay Water Quality to be Safe
According to an article in the San Diego Union-Tribune, a 1.5 million dollar, two-year study that examined the health risks of Mission Bay water quality and concluded that the park is safe for all forms of aquatic recreation, including swimming during dry, summer weather.
The study focused on individuals who had various amounts of contact with the water from full immersion to no contact at all. The individuals were contacted 10 days to 2 weeks later and asked if they had contracted any illness. While most individuals reported no illness at all, a small amount (less than 5%) reported minor illnesses such as skin rashes or diarrhea. The researchers concluded that the illnesses were not related to water quality, but likely due to skin sensitivity and the volume of water swallowed.
The study contradicts a popular notion that Mission Bay is unsafe for use most of the year. The idea originated in the 1980s when Mission Bay experienced many sewage overflows and pollution from storm drains throughout the year. Since that time, the city has spent more than 130 million dollars to upgrade its sewage system and reduce sewage spills that introduce bacteria into Mission Bay. The majority of storm drains in Mission Bay now have low flow diversions meaning that urban run-off is not entering the bay in significant volumes during dry weather.
Despite the multi-million dollar dry weather storm-drain diversion system that has dramatically improved the water quality in Mission Bay, there are certain times when the water is unsafe for use, including 72 hours following rain events that bring urban runoff into bay waters or following sewage spills.
The Mission Bay Epidemiology Study concludes there is no correlation between health risk and water quality during dry summer weather when urban run-off is not entering the bay in significant amounts. Previous studies have however established a correlation between significat urban run-off and health risk.
The policy of the Mission Bay Aquatic Center is to suspend "water contact" activities following significant rain when the County of San Diego Department of Environmental Health issues a 72 hour General Advisory for all water contact due to urban runoff contamination. (619-338-2073) .
According to Dr. Jack Colford who headed the study and reported his findings at the National Beaches Conference in San Diego, in the absence of wet weather or sewage spills, the water is safe.
"I have 4 kids and a wife," says Dr. Colford. "I'd be comfortable with them swimming there."
If you would like more information about water quality in Mission Bay or a "Think Blue- Easy Solutions for Keep Our Creeks, Bays, and Ocean Clean." pamplet, please contact us at (858) 488-1000 or by email at mbac@sdsu.edu.
SOURCE
Rodgers, Terry. "Water at S.D. park found to be safe." San Diego Union-Tribune 16 Oct. 2004. <http://www.signonsandiego.com/news/metro/20041016-9999-2m16swim.html>.
