Public toilets are notorious for unsavoury behaviour and even more unsavoury smells. The PPlanter is both a public toilet and a planter, composting the pee it collects to nourish pots of bamboo. And it's apparently odour-free.
This user-friendly, eco-centric design by Hyphae Design Laboratory in Oakland could also help cities in another important way: the PPlanter might be able to turn around our aversion to peeing in public.
The toilet works pretty much like any typical urinal. You step inside a small semi-private booth which is kinda like the typical bathroom stall (except it's on a sidewalk), and pee into a basin. After relieving yourself, you wash your hands using a foot pump, and the small amount of water "flushes" the urine to begin the filtering process.
The water and urine is run through a filter of charcoal and zeolite, which zaps the ammonia smell we usually associate with toilets. The cleansed wastewater is then deposited in the bamboo's planter, which further filters the urine with wood chips, straw, rock and styrofoam. By this point the urine is so diluted it's not damaging to the plant, only delivering the most helpful parts of our pee to the tree: nitrogen and phosphorus.
And there's good news for the ladies: Women can use a disposable funnel to pee standing up.
Hyphae tested their prototype last year in the Tenderloin neighbourhood of San Francisco to good local feedback, estimating that 300 people used the toilet per day. Now the city has ordered a permanent outdoor restroom that consists of two urinals as well as a composting toilet.
While there are plenty of public toilet prototypes out there with varying levels of privacy concerns and aesthetic challenges, even ones that gather urine for farming, this is probably the nicest-looking (and nicest-smelling) of them all. Plus it's a win-win situation for the community: Neighbourhoods that need public toilets the most are also most likely to need shade and sidewalk foliage, and bamboo is a generally indestructible plant that will grow in pretty much any condition. The PPlanter can capture all that yellow and turn it into green.