We have big problems with our water supply - winter is fine, dug a pond and bought a few old orange concentrate containers for collecting. Apart from having to suck the odd frog through the pipes - its fine.
In summer we rellie on the mains - which only really gets presure after all those other folk get home from work at 5 and finish their baths and showers at 10 - about midnight it normally gets a trickle.
Water takes a long time to stangnent - water that look dirty is often the first they will drink - not sating that they can tell the difference - but water you wouldnt drink (but could) is the water they love the best - no pollutions like chloride and the like.
One tip - better to carry a full container really slowly than a half full one fast.