Yes, we need water efficient farms (or, perhaps, farms in places that aren't so hostile to agriculture). But it's very hard to make a farm water efficient.
There are other places in the world to farm that are not currently suffering droughts.
Kind of a sweeping statement. Here's an inexpensive product that reduces water usage by 90%, aimed to farmers and especially good for citrus: http://treetpee.com/ttp-u/
For the record, I've lived in several places with water shortages since I was a teenager. I believe every one placed restrictions on certain activities (no washing car at home, water lawns only on designated days, no water for ornamental ponds, etc.) instead of simply raising the price of water.
I believe California could fix its problem with a lot less trouble by letting the price of water reflect its supply and demand.
Which would force a significant reduction in agricultural water use.
But the people making the decision would be people who know how much water their crops need, what the alternatives are, how profitable their crops will be in six months, etc. I simply don't have much faith in across the board cuts.
That is, I agree that water needs to be conserved. But I think there's a better approach; namely, letting the market work.