LOS ANGELES -- Amid an outcry over swelling numbers of homeless people, Los Angeles County public health officials are urging L.A. city to take action to provide basic sanitation -- toilets, handwashing stations and rat extermination -- for thousands of people living on the streets.

The requests, and a pledge to cooperate in trying to deal with problems arising from homeless encampments, are contained in a letter sent Friday and obtained by USA TODAY.

The thrust of the letter underscores the dilemma facing officials around the country dealing with large numbers of homeless people against the backdrop of an otherwise booming national economy: If cities are going to allow people to camp outside, they must provide basic services to protect public health and quell outbreaks of disease.

"Of concern to us are the public health risks that can arise from the persistence of trash (waste) illegally dumped in public spaces, rodent infestations, and lack of adequate facilities for personal hygiene and sanitation for the homeless encampments in the area," County Health Officer Muntu Davis wrote in the two-page letter to the homelessness operations chief of the city of Los Angeles.

Though other cities are trying to cope with encampments, Los Angeles has become the epicenter of the nation's homeless problem with thousands of destitute people living in tents or makeshift shelters pitched on sidewalks, under bridges or elsewhere. Many are in a squalid commercial district known as Skid Row. Other, smaller encampments are scattered throughout the county of 88 cities.

The county shocked local officials Tuesday in announcing that the annual homeless count rose to 58,936, up 12 percent from the previous year despite a Los Angeles Times calculation of $619 million spent the previous year on homeless housing. The count marked a reversal from the previous year, when the number dropped by 4 percent. The city's homeless count went up even more, 16 percent to 36,300.

The chairwoman of the board that runs the county, Supervisor Janice Hahn, called the numbers "very disappointing, very troubling, very sad."

Two days after the new figures were released, the county met privately with city homeless officials. to discuss illegal dumping and sanitation along Skid Row, as explained in the letter. The county and city wanted to identify areas where they can work together, like on the issue of illegal dumping.

Los Angeles Mayor Eric Garcetti, who briefly explored a run for the Democratic presidential nomination, has emphasized illegal dumping as the major problem on Skid Row amid a public outcry about sanitation issues there. Some businesses are believed to be leaving their waste there as a way to avoid paying fees to have it hauled away.

“Our streets are not dumpsters," Garcetti said in a statement Friday, adding the city would step up enforcement against illegal dumpers. But the letter makes clear that the focus should not be on dumping alone, that county has broader concerns, especially basic sanitation in order to prevent the spread of disease.

"If encampments are allowed to persist," Davis wrote that it is "essential" that street dwellers be provided not only with toilets, which are rare on Skid Row, but handwashing stations with soap, water and paper towels. While the county has asked for financial help in providing such basics, Davis said it is prohibited from assisting Los Angeles or any of the 87 incorporated suburbs.

It also says that the city needs to "provide adequate waste receptacles and routine collection services to ensure waste does not accumulate on the ground surfaces at and around encampments." The city also needs to provide for cleaning and disinfection from urine, feces and other waste on Skid Row.

The city's Public Works Department said it has been active in trying to clean up Skid Row.

It said it has 140 crew members with nine supervisors, more than triple the staff from three years ago. In addition, it said there are 102 trash cans in the area, which are serviced twice a day, seven days a week.

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