"How might prices be presented to the end user, though? With gasoline, you pay for every purchase, rather than having it piped into your home. I can think of a couple of ways: -Tech savvy customers might opt for daily or even instantaneous prices. -Others, such as the elderly, might get a weekly notice of the following week's guaranteed rate, or water providers may even have an averaged rate for those on fixed incomes, such as electrical utilities provide. The other issue is distribution. I imagine that cities would buy water wholesale, and charge end users on a cost-plus basis (adding maintenance of water lines and overhead of distribution to the wholesale cost)." - Kevin L