Development of biological nutrient removal technology in western Canada

Biological nutrient removal (BNR) technology for wastewater treatment was originally imported from South Africa in the early 1980s to protect the water quality of Okanagan Lake in central British Columbia from the effects of eutrophication. Since that time, more than 10 BNR plants have been built in western Canada, with capacities ranging from 2000 to 500 000 m exp 3 /d. As a result of the interaction among university researchers, plant designers, and plant operators, considerable progress has been made in refining the understanding of process and adapting the technology for cold climates. Consulting engineers from western Canada are now successfully competing in the international marketplace in the application of BNR technology in the U.S.A., the U.K., Europe, Asia, and Australia.