Our water comes from a 300' deep well. The generator provides current to run the pump. No electricity...no water. We also have two small ponds and a stone-filled catchbasin below the deck that collects rainwater. The flow from the roof via the downspouts and the outlet from the catchbasin are piped to a normally-dry percolation pond. In an extended emergency, I can line that pond to retain the water which of course has to be filtered for domestic use.
The deep-well pump is nearing the end of its lifespan and I'm considering installing a 12v unit when it needs to be replaced. Then I'll have to do the solar/wind/battery thing for grid-down situations. Not inexpensive to do right.

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