WME Environmental Management News
12th February 2007 

Australian buildings of the future will come complete with urine separating toilets and waterless urinals to supplement the shrinking stocks of phosphorus. The depletion of naturally occurring phosphorus is a growing global concern, heard a University of Technology, Sydney (UTS) workshop on Friday.

Phosphorus is arguably one of the most essential elements for life - and increasingly rare. Studies have shown global deposits of the mineral are unlikely to last more than 50 to 100 years says Dana Cordell, PhD student in the Institute of Sustainable Futures at UTS.

Australia's phosphorus-poor soil makes growing food a struggle, while phosphorous-laden run-off is impacting on waterways, which are becoming clogged by harmful algal blooms. While underground deposits of phosphorus are running low, there is another source: human urine.

Urine contains a high level of the mineral, is in ready supply and according to Cordell is a cheaper source than the mine site. It also reduces pollutants reaching waterways. The 'Phosphorus Urine, Sanitation Futures' workshop last week heard about global efforts to harvest phosphorus from urine, including in Sweden where there is a national target of recycling 60% of phosphorus in organic waste, including sewage.

"Urine is the single biggest source of phosphorous. It is costly to catch it at water treatment plants, but if you catch it in the toilet it is much more cost effective," she said. Also she said the waterless urinals would save water as well as capturing the precious mineral. Cordell said even though the thought may unsettle some people, phosphorus, whether from urine or underground deposits, is essential for agriculture. At least 30% of the phosphorus captured from Sweden's organic waste becomes agricultural fertiliser.

Cities are phosphorus hotspots and Cordell said if a feasible transportation system were made available the nation's phosphorus supply would be secured into the future. The UTS team hopes to establish a demonstration project to show how easily the resource could be captured and processed for reuse.