Flushing the toilet, washing the dishes, hands and body washing, cooking, all takes water.
Now you're confusing emergency life with normal life. Water is mostly reserved for drinking until the emergency is resolved. One should go into camping mode for an extended outage.
First flush is in the tank, but flushing can often be delayed. It also doesn't require using potable water. Pond/lake/ocean/stream/waterbed water is fine. There are also alternative toilets entirely, such as bucket and plastic bags.
Washing dishes...not important. Let them pile up for the duration or use paper products.
Hand sanitizer where required, some sponge bathing, but forget about regular baths or showers or hair washing. You may not feel as clean as you like, but you won't die.
Cooking is optional, but if one does one saves leftover water for a second use.