The problem has less to do with households than farms. 80% of California’s water goes to farming.
Where I live in Arizona, the water run-off of my roof would NOT keep me in water year around. The vast majority of the water falling on my 2 acres runs off into temporary rivers. The water supplier for my area has kept a pretty level pumping depth for the last 10 years, but hopes to bring in outside water to supplement it for continuing growth.
In Arizona, farming takes up about 70% of the state’s water.
Yes. It would not be a panacea, but it could buy time between “wet periods”.
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