by Mike White, President NMF&LB
No doubt you’ve seen something like the photo below, a set of solar panels attached to a water pump or a corner next to a circle that has a 2-3 acre solar panel system. Whether it’s for cattle or crops, New Mexico’s farmers and ranchers have been on the leading edge of solar use and technology. This is typical of our industry, we are early adopters of technology and on the forefront of conservation. We’ve had to reuse, recycle and reduce since the beginning of time since farmers and ranchers are typically far removed from major commerce areas and a run to town to buy something new was not an option.
We are also reducing our water usage.In fact, water used for food production declined from 3.4 million acre-feet in 1995 to 3 million acre-feet in 2010. Much of that decline is attributable to improved irrigation technology and modernized farming practices such as drip systems and concrete lined ditches. Farmers are also utilizing precision application which reduces evaporation and runoff. Variable rate irrigation uses soil moisture and topography to target specific areas for irrigation. And while it is true that food production accounts for an estimated 80 percent of New Mexico’s water use, it is also true that much of that water returns to aquifers or to rivers and is re-used downstream.
Another method for conservation is in seed selection. Plant scientists have developed varieties that require less water and as such are better able to withstand drought. By using these seeds farmers can maintain yield and quality while decreasing water usage.
And the crops farmers choose to grow in New Mexico are themselves conservers of water according to a 2011 report commissioned by the United Nations Educational, Scientific and Cultural Organization, titled “The green, blue and grey water footprint of crops and derived crop products” by M.M. Mekonnen and A.Y. Hoekstra, Hydrology and Earth System Sciences, 15(5): 1577-1600. The authors state that “Because the water footprint statistics have been formulated using the same methodology – the Global Water Footprint Standard – they are comparable and can be used to tell the complex story of water.”
To find the water footprint, a commodity’s water requirements were measured in green water (rainwater), blue for surface and groundwater and the grey water requirement is freshwater used to distribute nutrients and fertilizer. They are totaled for a “gallons per ounce” ratio where the lower is obviously better. Peanuts, grown on the eastern side of the state as a dryland crop, are given a rating of 4.7. This is excellent when compared against say, walnuts at 73.5 that are heavily irrigated. Not surprisingly rice comes in at 16.26 whereas lettuce, a big crop in the southern part of the state clocks in at .85 and onions are only slightly higher at 1.18. We produce a lot of milk with a ratio of 5.4 but that is better than pineapple juice at 6.36. So as you can see, crops grown in our state are already water savers.
Another agricultural group that has made innovations in water savings are New Mexico’s dairy farmers. They have been conserving water for years, using lagoon water for irrigation water in adjacent alfalfa fields. Their conservation efforts also expand to anaerobic digesters where recycled manure becomes renewable energy, helping again to save water that would have been used in energy production.
So when people talk about agricultural use of water or conservation, remember that the agricultural community is already doing their part to conserve and that growing food is not a waste of water!