Warning............... TEST TASTE ALL WATER before filling tanks or jerry cans.
I usually plan our trips with camp sites always located near a water source. Not necessarily for drinking, but for showering.
Drinking water I carry in the camper tank and jerry cans, recently bought a 100 liter plastic bag in a special sown baggie, advertised at the 4WD shows. When water supply becomes low at camp site, I make a run into nearest town and fill this up, lasts for ages. When empty folds/rolls up and is easily transported.