Since the construction of Greater Vancouver’s first sewers over 100 years ago, the ongoing planning and development of treatment facilities to keep pace with the area’s expanding wastewater needs has been a top priority in regional planning. Although nature has a remarkable ability to cope with small amounts of water pollution, the hundreds of millions of litres of sanitary sewage currently produced each day in Greater Vancouver would, without prior treatment, quickly overwhelm the natural purifying mechanisms of local rivers and marine waters. This includes, in particular, the Fraser River, one of the world’s richest salmon runs and an important habitat for a variety of marine and bird life.