My offgrid water system is pumped by solar power, and is gravity flow to the house.

I started with the house plumbed, but a not very functional water system. Two cisterns gathered water from springs that dried up in the fall and stored around 1200 gallons. But they were barely higher than the house and the only way to get water pressure was a pump with a pressure tank. I did not like this system, which barely worked, was noisy every time the water ran, and once leaked all over the living room.

I found a flat spot around 50 feet higher than the house, and installed two 550 gallon water tanks.

Repurposing an old, small set of solar panels, and a Shurflow pump with a linear voltage regulator, I found it was able to pump water up there from the cistern.

The cistern was cleaned out, re-sealed and water level sensors installed, so it will slowly fill up from the spring and then the pump will periodically pump out of it.

I hand buried around 300 feet of PEX pipe, 12 inches deep, to connect the water tank to the house, using a tool called a "whomper" which was easier than digging a trench by hand and refilling.

The system works great, I have 30 PSI now, and sufficient storage to easily get through the fall dry season.

For more see hacking water.

Also the overflow goes to solar powered waterfall.