The David Suzuki Foundation in Canada explains how water is used in Canada:
64% to power production operations: Power plants use water as a cooling agent to dissipate heat. In many cases, the water is returned to its source at higher temperatures, where it can have harmful impacts on the environment.
14% to the manufacturing sector: Water is so important to most industrial operations that the proximity to a water source is a determining factor in their location decisions. Unfortunately, in most cases, water withdrawn is returned in a polluted or otherwise altered state.
12% to municipalities: Water in municipal systems is generally treated so as to be of drinking water quality but obviously it is used for much more in our homes, by business and for fighting fires. While some water is lost due to evaporation or leaks, most water brought into the city flows out in the form of wastewater and sewage. The extent of sewage treatment varies significantly across Canada.
9% to agriculture: Water is primarily used for irrigation and the rearing of livestock. Due to high levels of evaporation, water used in agriculture isn’t returned to surface or groundwater sources. But farming and livestock operations are a significant source of water pollution.
1% to mining: Water is used in a variety of ways in mining activities. In most operations polluted water is returned to its source.