Yes, of course, it's true that you can tell farmers to use less water, but the Soviets proved how inefficient and unjust such command and control regulations are.
The Pacific Institute's flawed reports (and Peter Gleick) are cited as sources for these ideas, so let me remind everyone that:
- Farmers with water rights will use less when it's profitable.
- Most conservation measures (drip irrigation, for example) do NOT reduce waste if the water would have gone back into the ground or irrigation canal anyway.*
- Subsidizing farmers to install efficiency gear (as PI advocates) merely penalizes taxpayers.
- The best way to may conservation profitable is by allowing farmers to sell (consumptive) water that they do not use to other farmers, environmentalists and urban water managers.
* (via MM) The Supreme Court is examining prior appropriation in Montana vs. Wyoming and finding that the combination of first in time, first in right with quantified diversions (not consumption) is resulting in shortages for junior water users. In this case, Montana is getting less water as Wyoming farmers use "high efficiency" irrigation that reduces return flows. Time to quantify rights in terms of consumption.