Dirty snow is a real thing.
Groundskeepers at Fenway Park spread black sand on late-Spring snow to get it to melt faster without salt.
Resources have limited availabilities. Consumers of the water need to reduce their net consumption by finding ways to use less water, reduce waste water, and make better use of waste water.
If treated as a free market, as the reservoirs become more empty, water prices should increase to slow the rate of draw down. Nobody likes to pay more for anything, but that can be used to drive water use and water waste efficiencies.