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A blooming waste:
Su McInerney Marketing and Communication Unit

The earth's available reserves of phosphate, which is the primary ingredient in fertilizers, could be exhausted within the next 50 to 130 years. So why hasn't news of this looming threat appeared on media and other radar screens?

Environmental engineer and PhD student Dana Cordell says the problem hasn't been addressed because no one industry or authority has the responsibility and therefore the sense of urgency about the seriousness of the problem.

"Water authorities are increasingly concerned with phosphorus pollution from effluent discharges, which generate algal blooms in waterways; meanwhile agricultural authorities are faced with dwindling supplies of phosphate and higher costs to produce fertilizers.

"As fast as the world's population grows the reserves of phosphate are diminishing. However, it is possible both to slow the depletion of global phosphate reserves and to solve water pollution problems caused by phosphorus in wastewater discharges.

"I explored a traditional agricultural method used in Asia and more recently in Sweden that recycles scarce plant nutrients like phosphorus back to agriculture. This reduces nutrient loads in waterways and improves water and sanitation systems.

"Animals, including humans, excrete phosphorus in urine and faeces. I examined the benefits of urine diversion schemes to fertilise crops in Sweden and the barriers to be overcome before urine diversion and reuse systems could be implemented in Australia." Cordell says that in China nutrients in human urine and faeces have been used as a fertilizer for around 5000 years. Japan followed about 1000 years ago and it is a traditional practice in other Asian countries including Vietnam.

Sweden first started diverting urine to improve dry toilets in multi-story apartments in Stockholm in the late 1800s when it became too cumbersome for householders to empty mixed toilet waste on a daily basis. Small diameter sewer pipes were fixed to building exteriors, allowing the large volumes of urine to be diverted. In the 1950s dry composting urine-diverting toilets became common sanitation systems in Swedish summer houses.

"In the past decade," Cordell says, "several large scale demonstration projects have been undertaken in Sweden to divert urine from new housing developments and transport it to agriculture. At least two municipalities have mandated this system in new developments. "The key benefits are seen as capturing and returning valuable nutrients to arable land and the reduction of algal blooms in surface water bodies. The catalysts that made this change possible were the growing political environmental movement from the mid 1950s and the willingness of government to act. Sweden leads the western world in the research and application of this system, and other countries notably Norway, Switzerland and Germany are now researching and applying this technology.

"Can we imagine adopting this approach in Australia? Given our ongoing water scarcity and nutrient pollution problem, I think we have a wonderful opportunity in urban Australia to divert and reuse urine from waterless urinals. This technology is already in use to conserve water and save its owners money. The next step is to establish efficient collection and transportation systems to get it into agriculture."



Dana Cordell is studying for her PhD with supervisors from the UTS Institute of Sustainable Futures and Linköping University in Sweden. On completion her degree will be badged by both universities.