John Tolley, July 8, 2019
In our country, we've spent a good deal of money creating elaborate systems to carry our human waste as far away from us as is possible, and for good reason; it can be rife with illness-inducing organisms. Not to mention that sewage is, in almost every way conceivable, off-putting.
Despite all of this, though, researchers at the University of Illinois at Urbana-Champaign have found that on the whole human waste is a potential boon, both economically and environmentally, for society. For all of the malicious microbes populating human waste, it is a bountiful source of nutrients and water, one that has been woefully untapped.
Speaking with the University of Illinois news service, John Trimmer, a civil and environmental engineering graduate student and lead author of a study published in the journal Nature Sustainability, detailed how his team built on previous work in the field.
"In previous research, we have shown that human waste can provide a potentially valuable source of nutrients and water to enhance agriculture," said Trimmer. "In the new study, we expand this concept and set out to find connections between ecosystem services and the recovery of nutrients, water and organic matter from sanitation systems - then define and analyze the viability of pathways through which those recovered resources might further enhance ecosystem services."
The team combed through the 92,000 studies published between 2000 and 2018 that covered sanitation, resource recovery and ecosystem services. They found that only 155 dealt with the links between these fields.
As climate change and other environmental issues loom large, scientists are investigating any and all options to obviate a disaster. The Illinois research team was able to pinpoint 17 ecosystem services based around human waste, such as water and nutrient recovery, climate change mitigation and food provisioning.
While more work will be needed to move from this conceptual stage to a plan tailored specifically for an individual community or region, there is promise in revising how we engineer our sanitation systems to recover valuable resources rather than just flush them down the drain.