This article claims that California's "right to clean water" is delivering for poor people, but human right regulations are not strong enough to compensate for the ongoing pollution and poverty that seems to be part of industrial farmers' business model.
Indeed, this article points out how shows how tax liens on water bills hurt the poor and wreck communities far out of proportion to the money at stake (perhaps not accidentally), a problem I blogged on with respect to Detroit a few years ago.
Bottom Line: If you want water conservation, then raise prices. If you want to help poor people afford more expensive water, then give them money. If you want the water to be clean, then enforce pollution regulations. All the other actions are just a distractions from the root problems.