Potable water is an approximate proxy of energy costs. Find a scenario where energy costs increase 10-100x, and water will closely follow (not exactly, because

Potable water is an approximate proxy of energy costs. Find a scenario where energy costs increase 10-100x, and water will closely follow (not exactly, because when potable water costs in the US rise above a certain level, then people will change their habits, like not use potable-grade for watering their lawns, and not having lawns in the first place). Due to ongoing transition of developing nations into developed nations, and the tendency so far of the latter to decrease birth rates due to populations that embrace development trends responding to economic incentives, there is likely a cap on energy costs well below 100x.