I'd say it's a quite big one, "every city" has water towers to provide pressure to the people living in it, or they rely on the water source if it's higher up than the city.

There are probably exceptions, where this isn't true, but raised tanks make modern society possible.

https://youtu.be/yZwfcMSDBHs more on water towers, which are raised tanks of water.

We also pump water into fake lakes to later extract electricity from it. (https://youtu.be/66YRCjkxIcg)

Another good thing with water towers is that we can keep running the pumps at a lower RPM where efficiency than if we were trying to build a system with pumps to keep pressure.

Great channel if you're curious about everything related to humans relationship with water.

> I'd say it's a quite big one, "every city" has water towers

I meant not a big tank is needed for one house. I wasn't talking about the size of the use case.

> We also pump water into fake lakes to later extract electricity from it.

We do, because lakes are much much bigger than tanks on a house.

It depends what you're calling "not a very big one". On our farm we have a 5000 litre galvanised high tank for house-water.

Right, but do you need more than 50 of those for the specific purpose of evening out pressure?