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The San Francisco East Bay Area is in the throes of an #earthquake ‘drought’. Over the past several years, the following enquiry has been posed to local, regional and State of California officials:

72 hours post-earthquake, what are the citizenry to do when they can’t flush their toilets? 

Dry composting toilet and urine diversion systems are a decentralized and waterless form of ecological sanitation that can address all the post-earthquake sanitation concerns. They work by turning the human excreta into humus, and urine into a treated fertilizer. When well designed, these systems:

  • Exploit the nitrogen, and mineral, and organics nutrient flows.
  • Use no electrical power, drinking water, or fossil fuels.
  • Discharge no pollutants into the environment.
  • Have low capital and maintenance costs.
  • Are comparatively easy to maintain.
  • Can reliably destroy pathogens and can be a reliable way of breaking down excreted pharmaceutical residues.

Centralized sewer systems are also subject to catastrophic failure in a natural disaster, where sewer systems are expected to fail and be inoperable for a period of months, and possibly up to a year, with physical wastewater infrastructure damage amounting to between 75% to 100%. 

Oregon and New Zealand have studied container-based sanitation as a preparedness measure, planning for excreta to be segregated into urine and dry fecal-additive stores during the anticipated sewer failure, that can allow later composting and treatment of the materials so they can be recycled back to the environment.

Due to their improved carbon performance, composting toilet systems can help to promote climate stability. Carbon sequestered in soil makes up the bulk of the Earth’s non-oceanic carbon stores. And so, the creation of humus compost from composted excreta can help replenishment of the Earth’s topsoil, as well as be an important way to sequester carbon. After all, (wo)man’s poop is just anaerobically digested carbon…

#humanure #compost #excreta #carbon #sequestration #urban #peri-urban #earthquake