Urban runoff source of contamination

Alicia Robinson

Two new studies point to urban runoff as the delivery system for

bacteria and viruses that make swimmers sick in northern Orange

County.

A paper by a UC Irvine graduate, just published in the American

Journal of Public Health, says that urban runoff sickened surfers

using Newport and Huntington beaches nearly twice as often as those

surfing in rural Santa Cruz County during the winter of 1998.

Another study by a UC Irvine professor, to be published later this

month in the Journal of Applied Microbiology, says when looking for

potential health hazards in water, the state would be better served

looking for viruses rather than bacteria levels.

The studies are among a crop of recent research looking at the

causes of pollution in Orange County’s coastal waters. Studies

co-authored by UCI professor Stanley Grant, published online in late

March by the American Chemical Society, criticized the state’s beach

warning system as too slow to be effective, and on Thursday the

Orange County Health Care Agency cautioned about fish contamination

in Newport Bay based on preliminary results of a study still being

completed by the Southern California Coastal Water Research Project.

“These findings certainly aren’t going to be a surprise to anybody

who surfs in Orange County, but this is the first time it’s been

quantified,” said Ryan Dwight, a 2001 UCI graduate who wrote the

surfer sickness study for his PhD dissertation.

Dwight interviewed about 850 surfers about symptoms such as

stomach pain, fever, cough and skin infections and correlated those

with how often they were in the water during the winter in 1998 and

1999. His results showed that the more exposure to water surfers had

per week, the more often they reported symptoms, he said.

Dwight used Santa Cruz County as a comparison area because it’s

more rural and generally has better water quality and less runoff

than Orange County. Surfers there reported fewer symptoms in both

study years and reported close to half as many symptoms as Orange

County surfers in 1998, when El Nino storms were blamed for spreading

pollutants along the Orange County coast.

“What I think this study brings [to light] is quantified awareness

of this health problem and the need to address it,” Dwight said.

“Epidemiology studies need to be conducted with urban runoff.”

UCI environmental health, science and policy professor Sunny Jiang

studied viruses in urban rivers in Southern California and concluded

that current water-quality standards may not accurately depict the

amount of viruses in the water.

Water-quality resources would be better spent searching for the

sources of viruses in the water than looking for bacterial

contamination, Jiang said.

“I feel like if we are spending millions of dollars treating

indicator bacteria, which may be coming from multiple different

sources including soil, we are spending money in the wrong place,”

she said. “We could miss the target we’re looking for, which is

preventing human diseases.”

Her study also notes that urban runoff, which carries viruses into

coastal waters, should be managed better during storms to prevent

illness.

Runoff from urban areas, which can carry nutrients from

fertilizers and other chemicals, has often been targeted as the

culprit in coastal pollution.

“That’s why we’re diverting 2 1/2 million gallons a day off the

beach [into the sewer system], to try and minimize the impact of

those discharges,” said Ken Theisen, an environmental scientist with

the Santa Ana Regional Water Quality Control Board.

The water board is trying to stop runoff wherever it can, and

other agencies also are working on the issue, he said.

Dwight’s study probably overestimates pollution levels in northern

Orange County, but it is in the ballpark, Theisen said.

Solving runoff problems can be costly. Theisen estimates a

$250,000 price tag per storm drain to control runoff, divert it to

sewer systems, create a wetland treatment system or install filters.