[lio45]

Does Calgary have water meters? If not then that would be an obvious first step.

Over the years, I've noticed a significant difference in behavior between Quebec (where water is free and people use needlessly crazy high volumes) and Florida and France (where there are water meters and people pay attention to their consumption).

The kind of system you describe in Calgary has existed in my area of FL for as long as I can remember - there's the potable water line (metered) and there's also a non-potable water line (non-metered, IIRC) which is optional (not all properties have it; if you want one you pay the installation fee, and there might be a token yearly fee too, not sure) and people use it to water the lawn, etc.