When the delegates at an international conference on wastewater gathered in Vancouver last week they found themselves pretty much ignored by the media.
No TV cameras trained on the podium. No reporters waiting to interview the authors of the 90 papers from 30 different countries.
With speakers talking about such things as "a thermochemical approach for struvite precipitation modelling," the indifference of the mass media was perhaps understandable.
But Ken Ashley, an adjunct professor at the University of British Columbia and one of the conference organizers, thinks the world missed out on a big story - about how to take sewage and turn it into highly valuable fertilizer.
"It may be the biggest uncovered news story on the planet," he said in a post-conference interview.
What brought the 200 delegates to Vancouver was a looming global shortage of phosphorus and a groundbreaking nutrient recovery system developed at UBC.
Phosphorus is one of the essential elements of fertilizer. Without it crops whither.
The phosphorous in fertilizer comes from rock phosphate, which is mined primarily in Morocco, China and the United States.
Like oil, rock phosphate is running out.
The United States, historically the world's biggest producer, is expected to exhaust its reserves in 25 years. China recently slapped a 135 per cent export tariff on phosphate, choking off exports. That leaves Morocco sitting on one-third of the world's remaining supply - and reserves there are declining in quality and quantity.
"Phosphate production is going to peak around 2035 and then tail off," Dr. Ashley said. "If we don't do something we are looking at mass starvation."
Almost nobody is talking about the problem, however, because it doesn't seem real.
"Food is so abundant now the idea that there could be serious shortages just isn't on anyone's radar," he said. "Food is so cheap you just don't think about it not being available ... but all that food is based on the fact that farmers are fertilizing crops with phosphate ... and when we run out of phosphate, it will be worse than when we run out of oil."
There are alternatives to oil. But phosphate can't be manufactured - so once the natural supply is gone, food production will plummet.
That's where the conference on wastewater and the UBC innovation comes in.
Several years ago Dr. Ashley was researching how to restore nutrient-poor salmon streams by adding slow-release bricks of phosphorous.
He was looking for a supplier when he learned a team at UBC, led by Don Mavinic, an environmental engineer, and Fred Koch, a research associate, was working on a method of recovering a substance known as struvite from wastewater.
Struvite is a chemical compound (magnesium ammonium phosphate) that forms as hard crystals inside the pipes in sewage treatment plants, where it creates expensive maintenance problems.
The UBC team had figured out a way to capture struvite.
Dr. Ashley wanted to get some to fertilize nutrient-poor watersheds and was able to persuade BC Hydro, which has a fisheries compensation program, to come up with about $400,000 to fund the UBC research.
The result was the development of a struvite reactor, a recovery system that is so cost effective that within five years a sewage treatment plant can pay for the system by selling the fertilizer it produces.
Half a dozen plants are now in operation, including one in Edmonton that gets 300 kilograms of struvite a day from the effluent produced by 200,000 people.
Dr. Ashley said if the reaction of delegates at the Vancouver conference was any indication, similar systems will soon be in place around the globe.
In Canada, sewage plants discharge three trillion litres of effluent a year. That wastewater is often so rich in nutrients it pollutes watersheds. A private company formed to licence the UBC discovery, Ostara Nutrient Recovery Technologies Inc., can take that sewage, strip out the phosphorous and other nutrients, and produce a fertilizer, called Crystal Green, that is cleaner than the fertilizer produced from rock phosphate.
In a recent paper, Dana Cordell, a PhD student at Linköping University in Sweden, calculated the world's human population excretes about three million tonnes of phosphorus in urine and feces every year.
If that could be recovered, it would go a long way toward addressing the world's looming phosphorous shortage.
"Given that more than half the world's population now lives in urban centres, and urbanization is set to increase, cities are becoming phosphorus 'hotspots' and urine is the largest single source of phosphorous emerging from cities," she wrote in the journal Global Environmental Change.
Sewage plants have long been a big part of the pollution problem. Now, thanks to the work at UBC, they are about to become a big part of the solution.
One of the delegates at the Vancouver conference was Robert Kennedy Jr., an environmental activist and lawyer, who over the past 25 years has sued hundreds of U.S. sewage treatment plants for polluting rivers with effluent.
He is now a member of the Ostara board of directors.
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