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A cleaner solution to sewage

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Paul Clinton

Disinfecting Orange County’s sewage with chlorine may be new to

residents here, but the process dates back to the 1850s and has been

widely used by sanitary districts in other pockets of the country.

Last week, the Orange County Sanitation District joined many of

its peers in the waste treatment business by beginning a process in

which the sewage is soaked with industrial-strength bleach. After a

dechlorination chemical removes the bleach, the waste is released via

an outfall pipe on the ocean floor 4 1/2 miles out to sea.

The bleach, about three times more potent than the everyday

household variety, kills off much of the bacteria present in the

sewage, which is also treated with other methods.

“The fact of the matter is the chlorination-dechlorination process

will remove up to 90% of the viruses,” said Bob Ooten, the district’s

director of maintenance and operations. “We’re meeting our

disinfection goals.”

The sanitation district uses between 18,000 and 20,000 gallons of

bleach per day on the 234-million gallons of waste water released

into the ocean each day. It’s costing the agency about $8 million per

year to purchase the needed chemicals.

Sanitation district leaders asked regional water-quality

regulators in February if they could begin the disinfection as a way

of clearing the outfall pipe in the ongoing investigation into what’s

causing bacteria outbreaks along Huntington Beach and Newport Beach

shorelines.

A $5.1-million water quality study, funded by the district,

concluded that a multitude of onshore causes -- including leaky

sewage pipes, urban runoff and bird waste in the Santa Ana River --

could also be contributing to the problem.

“There is some evidence that the plume is coming to shore,” said

Key Tyson, an environmental scientist with the Santa Ana Regional

Water Quality Control Board. “[Disinfection] is providing further

protection to public health.”

On July 17, the district’s board approved a stepped-up treatment

method for the sewage. The decision came two days after the regional

board ordered the agency to begin chlorination by Aug. 12.

Local leaders aren’t enthused about chlorination, but say it could

be used as a stop-gap method until greater treatment of the discharge

can begin.

“It’s not the ideal situation,” Mayor Debbie Cook said. “If that’s

what we have to do, that’s what we have to do ... We would prefer to

have no bacteria or viruses in our outfall pipe, but that’s just not

the case right now.”

QUESTIONS EMERGE

Environmentalists have raised some questions about the

effectiveness of bleach in combating viruses in sewage.

Jack Skinner, an environmentalist and physician in Newport Beach,

said he worries that chlorination will give swimmers a false idea

about the cleanliness of the area’s beaches.

“If it hasn’t been treated to full [treatment levels], it takes

much more chlorine to kill off the bacteria and viruses,” Skinner

said. “You’ll get a false assurance. There’s not enough chlorine

added to kill off the viruses among swimmers.”

Other environmentalists say the process creates potentially

harmful chemical byproducts that could damage fish or plant life in

the sea. Doug Korthoff, one of the founders of the activist Ocean

Outfall Group, said the process creates “bad compounds.”

Officials defend the method, saying those byproducts don’t exist

in high enough levels to be harmful.

WIDELY USED

Orange County sanitation officials have begun chlorine treatment,

joining the nearly 400 other agencies that use the method statewide.

Agencies in San Francisco, Los Angeles, Lake Arrowhead, South

Laguna, Mendocino and other areas use it.

The Sanitation Districts of Los Angeles County, a joint-powers

agency that runs 11 sewage treatment and water reclamation plants,

has used chlorination on their waste since the 1950s, spokesman Joe

Haworth said.

“It’s a very effective tool for knocking the numbers of bacteria

down geometrically,” Haworth said. “That’s why you chlorinate your

pool.”

The Los Angeles agency uses a somewhat different method to

chlorinate its sewage, mixing the chlorine with lime, the same

chemical used to decontaminate drinking water in the trenches of

World War I.

Haworth said the agency spends about $2.5 million per year on the

chlorine, lime and bi-sulfite used to remove the chlorine before it

is released into the ocean.

REACHING INTO HISTORY

Water agencies have been chlorinating drinking water for more than

150 years. Back in 1850, John Snow first used the chemical to

disinfect the water supply in London after a cholera outbreak.

Regular chlorination of drinking water didn’t begin until 1897, also

in London. In this country, chlorination began for the first time in

Jersey City in 1908.

The more widespread adoption of the treatment method resulted in

one of the most important public health advances in this country’s

history, as doctors watched water-born illnesses like cholera,

typhoid, dysentery and hepatitis A virtually disappear from their

patients.

Today, local water districts like Mesa Consolidated still employ

the method.

“In order to avoid any development of bacteria, a very low level

of chlorine keeps [the water] from going bad,” said Diana Leach,

Mesa’s general manager.

Mesa uses small doses of chlorine, because the water it pulls from

the ground water wells is clear.

Using chlorine on sewage is another matter, so Orange County

Sanitation District officials use much higher doses of the bleach on

its sewage.

* PAUL CLINTON covers the environment and politics for Times

Community News. He may be reached at (949) 764-4330 or by e-mail at

paul.clinton@latimes.com.

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