The Economist's was, unfortunately, not as good as its audience (of the powerful) deserve, so I left this comment:
Sir --H/Ts to BB, ND and RM
Your article mixes (water) metaphors.
In the case of urban water, there is still plenty of space to reduce outdoor irrigation that current water pricing based on cost of delivery but missing a "price" for scarcity has clearly not discouraged. Second, farmers pay less for water because they self-supply via groundwater or irrigation districts using "rights" that they received for free, long ago. They cannot face higher "prices" unless (a) that State charges them a Public Goods fee for groundwater and/or (b) they can sell water in markets that would reconcile wildly varying values of water. Third, Israel's water management is totally inappropriate as an example for California, which has better relations with neighbors, a stronger environmental ethos, and far higher water availability.
The best way forward, as you might expect, is to induce better signals of scarcity for consumers by restricting depletion of common groundwater supplies and reforming policies to restrict demand within the bounds of supply.
* This post is particularly welcome, in drawing attention to the State's schizophrenic approach to water conservation targets. (I prefer a bottom up version of "live within you means" over pushing residents towards a state average, but sometimes you just gotta say "you're not even hitting your own [flawed] target."