Modern rice production in Australia is contentious but the farms claim a massive cost/benefit ratio in water use. Not just that it's efficient use of Australian water compared to other crops (almond groves for instance, very high value product but massive water input cost) but that it's more efficient than asian paddy rice for yield to water. I suspect the transport, processing and co-yield in protein isn't taken into account. Even so it could still be true.

The pan Asia rice research institute is a marvel. Heaps of work being done in yield, vitamin content, breeds for lower and higher water burdens and the golden rice.