My friend Phil King, a professor at New Mexico State University and water advisor to the Elephant Butte Irrigation District, has been following the water down through the Rio Grande southern New Mexico valleys as irrigation season starts:
For those unfamiliar with water management practices in Southern New Mexico, this is an odd place. The Rio Grande here, below Elephant Butte and Caballo dams, is turned off in the fall after irrigation season to store water. In the spring, it’s turned back on again, to deliver water to downstream farmers, who grow chiles, onions, pecans, and other crops with it. The dam was built in 1916, and irrigation season (even during the drought of the 1950s) always started in March at the latest. As Elephant Butte Reservoir dropped in the recent drought, that changed. 2013 was the first year irrigation did not start until May (skipping right over April). This is now the third year in a row the farmers have not received their first water until May.
I know little about release schedules. Is there an optimal flow rate that puts the released water into the ground and not into the Gulf? Is there an optimal flow time of day that puts more water into the ground and less into evaporation? Do farmers or native plants care about the timing and size of releases? Thanks.