Let's Talk Trash - Peecycling

LTT - July 2022  Peecycling

If you, like me, don’t have a flush toilet in your house, then you might also be a pee collector keen on saving your “waste” for the garden and compost bin. In general, I don’t announce to the world that I pee in a bucket and sh@! in an outhouse but since the New York Times spotlighted “peecycling” on June 17th and CBC’s As it Happens episode followed suit on June 21st, I decided to follow their lead for this month’s Let’s Talk Trash column. 

Until the invention of the sewage system, humans collected and used urine as a plant fertilizer (among other things). Urine contains a majority of the excess nutrients secreted by our bodies; nitrogen, potassium and phosphorus. These chemicals are commonly found in commercial fertilizers.  

A major question in this time of climate driven drought, water scarcity and food insecurity, is how to capture what is valuable from the waste stream? The current worldwide shortage of chemical fertilizer is encouraging growers turn to urine for the nutrients they need.  Side note: chemical fertilizers are unsustainable - manufacturing ammonia contributes to 2 % of the global CO2 emissions.

Some fascinating facts from the Rich Earth Institute, an organization in Vermont which collects and redistributes urine from the community to local farms: 

- 9 billion pounds of chemical fertilizer could be replaced with the urine Americans produce every year,

- 320 lbs of wheat could be grown in a year with the fertilizer from one adult’s urine,

- 125 gallons of urine is the approximate volume produced by an adult per year,

- 80% of the nitrogen and phosphorus pollution in wastewater is caused by human waste,

- more than 15,000 water bodies in the US are impaired due to nitrogen and phosphorus pollution, 

-1.2 trillion gallons of drinkable water is used to flush toilets every year, and

- the cost of phosphorus increase 270% between 1993-2013.

Gender, age and water intake effect the nutrient levels of pee but typically, fresh urine from a healthy person is sterile. However, if you are on antibiotics or prescription drugs, peecycling might not be recommended for garden application. The Rich Earth Institute, however, proposes that if we sprinkle pee on the land, a robust ecosystem can break down drugs or biodegrade them over time reducing or eliminating high levels before they reach a body of water and pollute it. 

Most of us are aware that lakes, rivers and coastal waters are directly affected by inadequate sanitation. The waste problem is compounded by chemical fertilizer run off from farms. The resulting algae blooms in our waterways trigger mass die offs of aquatic life and plants.

Pee can be pasteurized by storing it in a sealed container for one month in a room temperature greenhouse or heat it for 30 minutes in a solar pasteurizer. I store mine in buckets and use as needed.

If you are applying it to your garden, the dilution rate depends on the plant’s nitrogen needs, salt tolerance and condition of soil.At least 5:1 for nitrogen hungry crops like corn, squash, lettuce, onions, garlic, and brassicas. 10:1 for fruiting vegetables like eggplants, peppers, and tomatoes. 

It’s best not to fertilize with pee ‘tea’ every time you water. When the plant leaves are a rich dark green, you can back off. Yellow leaves indicate a nitrogen imbalance which pee tea can help restore. 

Urine can also go straight on the compost pile to speed up the composting process. Pee is considered ‘green’ meaning it’s nitrogen rich, so make sure you have adequate ‘brown’ – carbon rich - layers to mix into it.  Great sources of browns are untreated wood shavings, dead leaves, and shredded cardboard.

If re-purposing your own ‘waste’ stream appeals to you, there are several methods of collecting urine for later use, including the installation of pee diverters into outhouse or toilet set ups.

As global resources deplete and the need to become more locally resilient and self-sufficient increase, we are likely to see more innovative solutions like this one.