Since solar-powered toilets have started rolling in four afternoons per week, the streets in San Francisco's Tenderloin neighborhood have been cleaner.

These mobile bathrooms on wheels, guarded by attendants, have become quite successful in the region. City officials have said that Portland, Oregon; Honolulu and New York have inquired about them. They are seeking solutions for similar sanitation problems.

The portable pit stops have earned a lot of supporters. These supporters have said that the public bathrooms accessibility has made their neighborhood known for crime, homelessness and poverty more livable.

Jane Kim, a San Francisco supervisor whose district includes the Tenderloin neighborhood, said, "Everyone has to go to the bathroom, that's not something anyone can stop. This program affords people some dignity to take care of a human need".

There are two portable toilets with sinks, which are mounted on a trailer, hauled in by pickup trucks every Tuesday through Friday to three spots near soup kitchens and park areas that attract large number of people.

Dropped off at 2 p. m., the portable toilets are taken out at 9 p. m. to be cleaned. There is also a container placed for used syringes and trash cans near the pit stops.

The attendants, working for a nonprofit contracted by the city, ensure that the portable toilets stay sanitary and keep them stocked with toilet paper, air freshener, soap, paper towels and seat covers. They also give users a courtesy knock after five minutes.

Mohammed Nuru, director of the city's public works department, said that since the starting of the program in July, the requests for cleaning feces and urine off of sidewalks also have dropped by a third, from an average of 27 calls per weekday to about 15.

The pilot program has got inspiration from a group of students at De Marillac Academy, a private Catholic school in the neighborhood. The students read poems to city officials telling about their struggles growing up in the Tenderloin.

Many of the students said that, during those times, they had to pay close attention to the ground in order to avoid stepping on syringes and human feces.