Yuma Ag and You: How much water does it take to grow your lunch?

Bobbi Stevenson-McDermott     July 5th, 2015 publication

Water and weather, everyone including me is writing articles on the subjects. At the meeting of the International Water and Boundary Commission’s Citizens Forum held in Calexico, CA June 10th, members heard about a study analyzing the tremendous economic importance of the Colorado River to the basin region. The study was done by Tim James, Director of Research & Consulting, L. William Seidman Research Institute, Arizona State University.

The study requested by the Central Arizona Project, examines the economic importance of the Colorado for the Upper and Lower Basin Regions for 2012-Arizona, Colorado, Nevada, New Mexico, Utah and Wyoming as well as seven contiguous counties in Southern California; Imperial, LA, Riverside, San Bernardino, San Diego and Ventura. The economic values are estimated based on: non-availability of Colorado River water for one full year (2012); Non substitutability of the Colorado River water, no other sources available to make up for the loss of river; and non-adaptability of producers and consumers. The study has a lot of shock value and no real solutions to the hypothesized conditions but the top 5 affected gross state product sectors were real estate-$174.3 billion; healthcare and social services-$148.6 billion; finance and Insurance-$137.1 billion; professional, scientific and technical services-$ 130.6 billion and retail trades-$96.2 billion with the total loss for the state of 59.9 percent of gross state produce. The study did not evaluate agricultural jobs or economic impact of agriculture. Mr. James did do estimated job loses by sector for the 7 California counties, and agriculture was the sector that lost the fewest jobs. The comment was made that you could just do away with Agriculture in the region and buy food elsewhere.

Buy our food from whom? These studies are so frustrating because they seem to be trying to convince Americans that US agriculture is unnecessary because of the low percentage of the population engaged in food and fiber production.

Almost as annoying are the newscasters speaking about the amount of water needed to produce an almond. Each almond, according to broadcast news takes a gallon of water to produce. And your point is?  You are going to have to eat something, and everything you eat, wear, drive or live in takes water in varying amounts.

What is not well understood is the huge amount of water that is indirectly delivered to cities in the form of food. A report by the Water Education Foundation documented the amount of water to produce various foods in the Western U.S. Their basic approach was to divide average evapotranspiration by average yields to determine the gallons of water per pound of food produced. Since some of the water delivered to a farm is unavoidably lost as deep percolation, runoff or soil moisture storage, the irrigation efficiency was assumed to be 70 percent.

Using a typical 2,300 calorie menu proposed by the USDA, the following meal was constructed. The gallons (gal) of water required to produce that particular food item are noted.

Breakfast:     Medium orange, 14 gal; 2 eggs, 126 gal; 2 slices of toast, 22 gal; 2 pats of butter, 92 gal; 1 cup of milk, 48 gal; one fourth cantaloupe, 40 gal for a total of 342 gallons of water

Lunch:          Taco salad with tomato, lettuce, hamburger, chips and cheese, 806 gal.; one quarter cantaloupe, 40 gal for a total of 846 gallons

Snack:          one quarter cup almonds, 160 gal;1 cup yoghurt, 88 gal, 1 cup orange juice, 49 gal for a total of 297 gallons.

Dinner:          Chicken-broccoli stir fry, 160 gal; 1 cup rice, 50 gal; two slices bread, 22 gal; two pats of butter, 92 gal; fruit cup, 35 gal; 1 cup milk, 48 gal for a total of 427 gallons.

Your total water intake for the day, through your food is 1,912 gallons per day.

Do farmers us a lot of water, yes., and we benefit tremendously from their productivity. The water may not come from our faucets but is in every bite we take.