The city of San Francisco, tired of cleaning up after those who relieve themselves in the public, wants to test walls that pee back.



The San Francisco department of public works (DPW) is hoping to paint some of the city’s walls with hydrophobic (water-repellent) paint. If urinated upon, the paint makes the urine bounce off the wall – and back at the urinator’s feet.

In Europe, such paint has been proven to work. In Hamburg, walls in the St Pauli quarter of the city have been painted with a super-hydrophobic coating and given accompanying signs, which read: “Do not pee here. We pee back!” It was the Hamburg experiment, as captured in a YouTube video, that captured the attention of San Francisco officials.

“We saw this report on the internet and thought it looked interesting,” DPW chief Mohammed Nuru told the San Francisco Chronicle, adding that the city is considering testing the paint in neighbourhoods where “it’s costing us a lot to send teams out and do clean-up”.

Public urination is a long-held and growing concern for San Francisco residents, according to the Chronicle. The city passed legislation against it in 2002 but the ban has had a little success, even though fines for answering nature’s call on San Francisco’s streets can range from $50 to $500.

“We know it’s a problem and we’re out there – our foot beats and our mobile patrol units. We’re out there trying to enforce these kinds of violations,” a police spokesman, Sergeant Dennis Toomer, told the Chronicle in 2007. “When we do spot something we take action on it, but we have limitations. We’re trying our best.”

In the first six months of that year, San Francisco received 5,636 requests for steam-cleaning sidewalks, the majority of which were caused by human waste.

Hamburg faced a similar dilemma, according to IG St Pauli, the community group that decided to paint walls to repel urine.

“Prohibitions and fines do scarcely anything,” said a member of the group. “So we decided to solve the problem our own way. Now, St Pauli pees back.”

Suggestions for where San Francisco should test its pee-back walls can be submitted to dpw@sfdpw.org.

“If a suggestion sounds reasonable, we’ll try it,” said Nuru.