No nasty smells here (Image: Anastasia Victor)

It is almost impossible to find a public toilet in the US – and that creates problems. When desperate people pee in doorways and alleys, it offends residents and drives customers away from local businesses.

Enter the PPlanter, a public urinal with an ecological twist. It uses biofilters – plants in a growing medium – to treat urine. Easy to move, it consumes less water than the average toilet and sink, while avoiding the harsh chemicals of conventional portable toilets. On top of all of that, its inventors claim it is odour-free.

The small booth of the PPlanter is not just for men: disposable funnels allow women to use the PPlanter standing up. The treatment process begins once the user washes their hands at a built-in sink. A foot pump pushes clean water through a faucet. The rinse water does double duty by flushing the urinal.


The water and urine empty into an air-tight tank; without exposure to air, urine does not produce malodorous ammonia. The liquids are pumped into a pallet-sized biofilter that is lightweight and movable, containing bamboo, wood chips, straw, rock and pectin-coated styrofoam. The bamboo takes up the water as well as nutrients in the urine, including nitrogen and phosphorus. Bacteria break down protein and carbohydrates. That leaves only salts.

Unconventional relief

The PPlanter was designed and built by the Hyphae Design Laboratory of Oakland, California. The idea was to reduce public urination while challenging people to rethink conventional plumbing. “Our goal is to refocus attention to developing ecological sanitation, making it aesthetically pleasing, clean, functional, and cool,” says lab founder Brent Bucknum.

Last year, Bucknum and his staff tested the PPlanter in a crowded San Francisco neighbourhood. It stood up well to heavy use and has relieved as many as 300 people over an 8-hour period. Now the city has ordered a permanent one with two urinals and a composting toilet. With proper maintenance, it should last 10-15 years. Additionally, Bucknum plans to rent PPlanters for festivals and events.

Bucknum hopes that international development agencies will be interested in installing PPlanters in nations lacking sewer infrastructure. But there is also a potential market close at hand, in dense neighbourhoods like those of San Francisco.

“The PPlanter is lower cost and lower maintenance than any other kind of toilet,” says Darryl Smith, co-director of the Luggage Store Gallery in the city’s Tenderloin neighbourhood. An outdoor portion of the gallery hosted a PPlanter for three months during testing, and he hopes to get one permanently. “The openness of the design keeps people from taking over these toilets to do drugs or other unhealthy things. It makes it safer.”