Regarding water storage (remember, I live in the Middle East)

The houses of my father and two brothers do have underground water tank that receives the city water, then a pump pumps it to a tank on the house roof. My youngest brother's house, for example, has a eight-cubic meters (~ 2000 gallons) tank underground, and two x 2.5 cubic meters tanks on top. These two tanks feed the house by gravity.

This seems to be standard around here (tanks sizes may vary). I wonder if someone in your part of the world has thought of similar water system