CONCORD, Calif. (AP) -- Standing on the edge of a swimming pool gone bad, public health worker Jeremy Tamargo scoops up a s38le of murky, brown water to make sure the mosquito treatment he administered earlier is still working.
A collection of plastic toys stashed in a corner of the yard and a stuffed toy floating forlornly in the sw38y water indicate a family once played here, until foreclosure forced a move.
Now the once-sparkling, turquoise jewel is a "green pool," a legacy of the foreclosure crisis - and a breeding ground for millions of potentially disease-carrying mosquitoes that have kept health officials busy in California and elsewhere.
"It's always in places where you least expect it," said Tamargo, who is on the front lines of finding and treating abandoned pools in Contra Costa County's suburbs east of San Francisco, an area with large numbers of foreclosed homes. "Could be a $500,000-home neighborhood, could be a million-dollar home neighborhood, and in the back yard there's this."
Authorities can order owners to take care of properties, for instance, treating or draining pools. The problem is finding who's responsible for an empty house that may have been flipped more than once.
"If you're a building official or a zoning inspector for a local government you really have to become almost like a CSI investigator just to track down who you should be talking to," said Joseph Schilling, director of policy and research for the Washington, D.C.-based National Vacant Properties C38aign which focuses on the problem of abandoned houses.
"Nobody wants to take responsibility," said Tamargo. "I guess they figure because they're not living here or whatever it's not their problem any more. The banks - this is probably the least of their worries."
So, for something that can't wait, like green pools, local officials fix the problem themselves and then try to seek reimbursement.
In an effort to force ownership of the problem, officials in Chula Vista, a city south of San Diego, passed an ordinance requiring lenders to notify the city after recording a notice of default if the property is vacant, pay a $70 fee and hire property management firms.
The ordinance has been in effect for a month and so far there have been about 30 voluntary registrations and notices of violation are being processed for another 30, said Doug Leeper, code enforcement officer.
Chula Vista, a city of about 175,000, has hundreds of homes in foreclosure, so, for now, the city has been fixing what has to be fixed, "having to put the money up front we really don't have," said Leeper.
Efforts to quash green pools got a boost earlier this year when California's Gov. Arnold Schwarzenegger declared a state of emergency, providing about $6 million for mosquito control, surveillance - including flyovers to look for the telltale signs of oblong and kidney-shaped brown blotches - and information c38aigns urging neighbors to report neglected pools. The state has a hot line, 1-877-WNV-BIRD, for reporting possible signs of trouble such as green pools or dead birds. (Birds host and transmit West Nile virus.)
Statewide data on green pools aren't available, but "we certainly recognize that the high number of foreclosures contributed to virus transmission in urban areas this year," said Vicki Kramer, chief of the California Department of Public Health's vector-borne disease section.
As of early November, there were more than 370 cases of West Nile virus reported in California and 16 related fatalities, four from Kern County, which had some of the highest foreclosure rates in the state.
The year-to-date total is higher than last year's total of 278 cases and 7 deaths, but is lower than officials had feared, said Kramer, who credited the emergency declaration with warding off a bigger outbreak.
Health officials say earlier in the year it looked like the state was on pace to rival the totals posted in 2004-05 (around 800 cases both years) when the virus first hit the state, targeting susceptible populations.
About four out of five people who are infected with West Nile Virus won't show any symptoms, which include fever, nausea, headache, and muscle aches. But in very rare cases - about one in 150 - patients will develop severe illness, including meningitis or encephalitis.
What authorities do with green pools varies by jurisdiction, with some preferring to treat while others drain, said Leeper.
Draining untreated pools can be a problem because larvae can spread through the storm water system. On the other hand, chemically treated water isn't supposed to go into storm water, he said.
One solution he's seen is to pump the water over a yard, where the larvae are caught up in grass. Draining can damage pool walls, raising a liability issue, although Leeper's not particularly swayed by that concern.
In Contra Costa County, officials estimate they spent less than 1 percent of service calls on swimming pools last year, compared to having technicians spend up to half their time inspecting and treating pools this year, said Deborah Bass, public affairs manager for the Contra Costa Mosquito & Vector Control District.
It's not always easy to tell for sure if a pool's fallen victim to foreclosure or has been neglected for other reasons, but about half those pools were confirmed as foreclosures, Bass said.
Officials elsewhere in the country have reported similar problems.
In the Southern Nevada Health District, home to Las Vegas, officials logged nearly 1,600 complaints of standing water, primarily green pools, by early November compared to just over 1,000 for 2006, said Vivek Raman, vector control program supervisor.
"Some of them are just so thick with green scum on top," said Raman. "I've seen pools that have millions of mosquito larvae in them, literally millions."
Peak breeding for West Nile virus-carrying mosquitoes is mostly over for this year, but the problem of foreclosures isn't going away anytime soon, said Schilling.
"My sense is that the foreclosure crisis is going to rival the savings and loans debacle of the 1980s, at least as far as community impact," he said.
