The enormous sewage spill soiling San Diego's coast poses serious health risks for surfers, divers, or swimmers who disregard warnings and take a dip in contaminated water, officials said Tuesday.
While there is a looming health hazard, environmentalists said the ocean and ocean floor should recover rapidly if it doesn't take too long to fix the ruptured sewage pipe.
With 170 million gallons of treated sewage pouring into the sea from the leaking outfall pipe off Point Loma, health officials are trying to prevent water enthusiasts from getting near the contaminated area--a feat that has proven tricky this week as big waves have beckoned enticingly.
"We're concerned about the surfers, swimmers and scuba divers," said Dan Avera, assistant deputy director of environmental health with the county's health department. "We don't know what the odds are, but because of the volume of sewage, there's increased likelihood of somebody contracting some kind of illness."
Health officials also say consumers should not eat local shellfish, such as scallops, that might have been harvested from the polluted waters. Fish, however, that is cleaned and cooked poses no hazards, Avera said.
Those who disregard the warnings and plunge into the water face the possibility of contracting a range of diseases including eye infections, gastroenteritis, skin rashes, dysentery and hepatitis.
In fact, so serious are the risks that officials recommend that anyone who comes into contact with the contaminated water shower immediately.
"Boating is not a problem," said Ruth Covill, an environmental health specialist with the county. "But if you fall in the water . . . take a shower with lots of soap immediately."
Health officials cannot completely assess the health risks posed by the spill until they learn the extent of the contamination and determine how long the sewage will continue to spew into the ocean--two big questions that have not yet been answered, though officials have said it may take up to two months before repairs are complete.
"The longer the spill continues, the greater the likelihood of human health effects," said Cedric Garland, an associate adjunct professor of community and family medicine at UC San Diego's medical school.
Between 75% and 80% of the solids have been removed from the sewage currently pouring into the ocean. But the material still contains bacteria, as well as viruses, that can enter the human body through a number of ways: cuts in the skin, through the nose or small amounts of water that every swimmer inevitably swallows.
The possibility of viruses poses the gravest danger, as viruses can cause diseases such as hepatitis A, a potentially fatal liver disease. Scientists, though, believe that municipal sewage contains about one virus for every 50,000 to 100,000 chloroform, or bacteria, Garland said.
"But the viruses are the biggest worry because they cause the most serious disease and survive longest," Garland said.
The best preventive measure is totally avoiding the contaminated water--as well as locally harvested shellfish, experts say.
"The health consequences will depend on the behavior of people in the city--if warning signs are disregarded and shellfish are harvested or people swim, dive, or surf in the contaminated area, then there are possibilities of diseases," Garland said.
Marine biologists predict that the ocean environment will be able to recover fairly soon from the gallons and gallons of pollution. But this, too, will depend on how long the spill goes on.
"My prediction is that it probably won't have a lasting effect," said Paul Dayton, a professor of marine ecology at Scripps Institution of Oceanography.
Dayton and others predict the sewage will "dust," or leave a thin cover, on the ocean bottom--possibly smothering kelp, arthropods, starfish and urchins that live along the bottom.
"But I think it would be a mistake to make this sound doomsday," Dayton said. "My prediction is that it won't be serious."
Experts believe the ocean currents and waves will help disperse the mess, spreading it south on fast-moving surface currents. The sewage is entering the ocean at a depth of 35 feet and three-quarters of a mile from shore.
"Because this is happening in pretty shallow water, it seems to be rising to the surface and floating away," said Mia Tegner, a Scripps research marine biologist.
Unfortunately, the effluent may well set back efforts to cultivate kelp beds in the area that had been depleted by sea urchins. From now until spring is prime time for kelp growth--and the spill threatens to prevent a resurgence of kelp in the area.
With no kelp, the area offers far less food and hiding spots favored by fish and other sea creatures such as abalone.
"We were hoping the kelp would recover--if this spill goes on, it's going to hinder that recovery," Tegner said.
Many ocean experts voiced optimism that the contaminated waters would bounce back, beginning as soon as the spill is halted.
"I wouldn't expect any long-lasting effects," said Jeffrey Frautschy, former deputy director of Scripps. "In cases where there have been major discharges, the change back has been very rapid--once the discharge stops."