Just a cheerful reminder that almost half the water we put into our system is lost along the way.
Also, I live at a rural property with rain water tanks, and we have a reasonably small tank for the size of our house. We haven’t come close to running out of water this summer, while we have had to get a tanker other years. It’s actually been a reasonable summer in terms of rainfall.
I imagine the salinity would cause all sorts of issues, and as you say just having one source is better when things work as they should