L.A. Bets on the Great Gray Hope : Drought: City officials are looking into using water from showers and washing machines for irrigating plants and trees. The county sees a potential health risk.


One source of nourishment for drought-parched trees and shrubs in Los Angeles may literally be going down the drain, and a City Council member is hoping to stanch the flow.

At the urging of Harbor-area Councilwoman Joan Milke Flores, city officials are considering a proposal that could lead to the use of waste water from washing machines, showers and bathroom sinks for underground irrigation of neighborhood plants and trees. Flores sees the recycling of so-called gray water as one answer to persistent drought conditions and a projected long-term water shortage for the city.

The idea, however, has run into stiff opposition from county health officials, who have warned the city that recycling gray water would pose serious public health risks. Gray water is different from so-called black water, which is water flushed down toilets.

Drought-scorched Santa Barbara and San Luis Obispo counties have approved gray-water programs, but recycling the waste water is illegal in Los Angeles County and most other parts of the state.

"If it surfaces, you have potential unsafe water that would carry disease organisms," said Jack Petralia, director of the county's Bureau of Environmental Protection. "People assume that wash water from the washing machine is safe. That is not true. . . . There are potential (viruses) in that water."

County health officials killed a similar proposal in June by county Supervisor Michael E. Antonovich, who had recommended the county reconsider regulations that prevent homeowners countywide from redirecting gray water from drain pipes to other household uses.

"If this water can be recycled and used to water our plants and grass, it would stretch our limited water supplies and help us meet our conservation goals," Antonovich told the Board of Supervisors.

But county health and public works officials responded with an eight-page report that characterized gray water as a health hazard and recommended against any changes to the county health or plumbing codes to allow its recycling. The report referred to a study by the state Department of Health Services, which concluded last January that the public should not handle or recycle the water.

"If more than one person resides where gray water is used and one sheds infectious organisms into gray water . . . undisinfected gray water can be a mode of transmission for infection," the state report said. "In susceptible persons, infection can result in disease."

Officials in Santa Barbara and San Luis Obispo counties, however, report no major problems with gray-water irrigation systems, which were legalized in Santa Barbara County last year and in San Luis Obispo County earlier this year because of severe drought conditions. The counties require that the gray water be distributed underground--away from human contact--through small leach fields, which are narrow trenches filled with gravel and topped with soil.

"It saves anywhere from 25 to 40 gallons of water per day per person," said Larry Farwell, water conservation director for the Goleta Water District near Santa Barbara. "People have been able to maintain many plants that they would not have otherwise."

Farwell said Santa Barbara County health officials raised concerns about the water, but recognized that residents were installing gray-water systems even without county approval to keep their trees and shrubs alive. County officials, he said, eventually concluded that it was better to regulate gray-water usage than to ignore it.

The apparent success of the Santa Barbara and San Luis Obispo programs encouraged Los Angeles city officials to explore the idea several months ago. Although drought conditions are less severe in Los Angeles and bootleg gray-water systems less prevalent, officials said gray-water usage could become important in coming years because of population growth and reduced water imports for the city from the Colorado River and the Mono Lake basin.

Los Angeles water officials, at the direction of Flores and council colleague Ruth Galanter, have been devising a demonstration project to test gray-water systems. The councilwomen instructed officials last month to come up with a demonstration site where various gray-water recycling proposals--including such ideas as redirecting shower water to toilets--could be monitored and analyzed. No site has yet been selected.

"We are not going full scale on this yet," Flores said at a recent council committee meeting. "Let's try it, see what the problems are, see if we can fix them and go on from there."

But the head of the city's water reclamation office has said he will recommend that the council abandon the demonstration project because of opposition from county health officials. Bahman Sheikh said it would be too difficult to move forward without county support.

"I am personally disappointed," Sheikh said. "But of course, we will have to do things in an orderly manner. We couldn't possibly recommend to the city to go against the county health department's feelings on this."

Flores, who first suggested recycling gray water last May as part of a 10-point water conservation proposal, said she will not give up. She said she will ask Sheikh and other city officials at a meeting next month to move forward with the demonstration project even without the blessing of county health officials.

"Burying your head in the sand and saying we find that it is unhealthful is not a real answer," Flores said. "I think that particularly people interested in health should be willing to have somebody like the city of Los Angeles do a demonstration project because that could help their research."

Flores said the demonstration project would be conducted under controlled conditions and would not involve the public, thereby addressing concerns about infectious waste water harming residents. Only if the experiment is successful, she said, would the city have to worry about how best to introduce gray-water systems to the public.

State health officials said they were not familiar with the Los Angeles proposal, but said they generally do not object to the use of gray water if the system is contained underground.

"I am not against the use of gray water when done correctly," said Michael Kiado, senior sanitary engineer for the state Department of Health Services' environmental management branch. But he added that "there needs to be assurances that people are not using more gray water than the local soil conditions can keep underground."

The simplest and least costly gray-water system involves redirecting waste water from a household washing machine to an underground "leach field" of gravel located near trees and plants. The washing machine's discharge hose is connected to a pipe that drains into a surge tank, often nothing more than a trash barrel. An outflow pipe extends from the bottom of the tank and connects to an irrigation line, which runs underground and dumps into the gravel trench.

The system also should include a diverter valve, so gray water from the washing machine can be directed back to the sewer line when rain or excessive irrigation has saturated the soil.

Petralia, the county health official, said the city has the authority to conduct a demonstration project without county approval, but he questioned the wisdom of such an experiment. Petralia said it would be difficult to duplicate the conditions in the real world, leaving open the possibility that a successful experiment would falsely encourage residents to try systems of their own and ultimately expose themselves to health hazards.

"I have no doubt that in a terribly controlled pilot project, the system would work," Petralia said. "But that doesn't prove anything in terms of carrying it into the general population. . . . The general public doesn't take care of these kinds of things. You would have to have a system that took no maintenance, and once it was there it was out of sight and out of mind. And there is no indication that any of these systems would do that."

Flores disagreed.

"There are a lot of other things that we don't just ban because in the wrong hands they are used the wrong way or that without permits they are unhealthful," she said. "If we did that, we wouldn't be using electricity at all. If we didn't have electricity today, and they came with a proposal to approve electricity before the council, and they showed pictures of people's hair standing up, and they touched this wire and they dropped over dead, or they became a human torch, we would never get that approved."

Sheikh, the city's water reclamation chief, predicted interest in gray-water usage will diminish over the next few months as winter rains ease concerns about drought conditions. He said the debate will resume next summer, however, if the region experiences a fifth year of drought.

In the meantime, he said, the city is concentrating its conservation efforts on finding uses for reclaimed water--treated waste water that has been used to irrigate parks, golf courses and other landscaping. Sheikh said potential water conservation from reclaimed water far exceeds that from gray water--and county health officials have not objected to its use.

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