UBC Reports | Vol. 49 | No. 2 | Feb. 6, 2003

UBC Sewage is Not a Waste

It’s a dirty job, but UBC-developed technology is leading the way in how to do it

By Michelle Cook

It operates out of a humble looking pair of trailers parked alongside a ditch at the south end of campus, and it’s been quietly helping to clean UBC’s sewage for almost 20 years. But only lately have people worldwide begun to recognize the profound advances in waste water treatment that have been made at the university’s Biological Nutrient Removal (BNR) Pilot Plant.

The small-scale pilot plant was built by the Civil Engineering Dept.’s Environmental Engineering Program in 1985. One of only two facilities of its kind in Canada, it treats about five per cent of the sewage generated on campus. This year the plant, the program and the department have been nominated for the prestigious Stockholm Water Prize. The international environmental award, on par with a Nobel prize, honours outstanding achievements in the protection of the world’s water resources.

It all started with a few bugs.

The BNR plant uses naturally occurring microbes -- or bugs -- to remove nitrogen and phosphorus from the university’s waste water. Once removed, these elements become by-products that can be re-used as fertilizer. It’s an environmentally friendly approach to waste management that can also generate revenue through the sale of the fertilizer by-products. More and more municipalities worldwide are adopting it -- based in large part on the research done at UBC over the last 20 years.

“We look at waste as a resource,” says Prof. Don Mavinic, group leader of the Environmental Engineering Program and one of the BNR plant’s founders. “If you look at it, it’s a product, not a problem, and we call it integrated environmental technology.”

Treating waste biologically is cheaper than the more conventional chemical method, Mavinic says. Unlike chemicals, there are no purchase costs, or costs to dispose of chemical-laced sludge that can’t be put in landfills or incinerated.

“We basically set up the temperature and pH conditions for the bugs to do their thing, and they merrily go around and do the work of removing the nitrogen and phosphorus from the discharge stream,” Mavinic says.

Helping them to get the mix just right is UBC’s Dept. of Microbiology and Immunology, which has provided advice and research on the best “bugs” for the cleaning job. To date, 17 PhD students and 25 MASc students have carried out research at the facility.

The idea of getting bugs to do the dirty work wasn’t developed at UBC. The technique originated in South Africa, but only for use in one temperature condition, making it ineffective in harsher climates. Bill Oldham, now professor emeritus in the Civil Engineering Dept. and another founder of the BNR plant, pioneered a way to adapt biological nutrient removal technology so that the bugs could do their work in all kinds of temperature conditions.

Today, advanced nutrient removal treatment technology is being purchased by municipalities around the world to treat their waste water. Globally, more than 20 per cent of eligible facilities have already adopted the biological approach. Canada’s prairie provinces have switched over completely to biological nutrient removal techniques.

“We’ve developed a research and knowledge base that no one else in the world has at this scale,” Mavinic says. “Municipalities from the European Union to Australia are purchasing and adapting the technology to treat their waste water.”

The nitrogen and phosphorus-rich sludge by-product can be used in mining reclamation and in forestry activities. UBC is currently involved in projects at B.C.’s Kootenay and Arrow Lake dams to use fertilizer recovered from the BNR plant to help restore the balance of the nutrient content in the dams’ reservoirs.

UBC has also partnered with B.C. Hydro, the municipality of Penticton, B.C. and the Greater Vancouver Regional District on a project to research the use of a pure phosphorus fertilizer, known as struvite.

This year’s winner of the Stockholm Water Prize will be announced at the end of March.