Treatment of industrial waste water is one of the biggest and most urgent environmental challenges of our time. All major energy production and manufacturing industries require water as a critical input. In 2013,Statistics Canada estimated the yearly national usage at approximately 30.2 billion cubic metres, resulting in 700 million cubic metres of unusable waste water. This waste water is often kept in large settling ponds for decades, and waiting for the containments to slowly rupture down,putting the water supply at risk for spills and leakages.
Source: phys.org