Yuma farmland powered by billions of gallons of water

More than 50,000 acres of farmland span across the Yuma Valley and require somewhere in the neighborhood of 370,000 acre-feet of Colorado River water per year to be delivered by the Yuma County Water Users' Association (YCWUA).

Manager Tom Davis noted that one acre-foot of water converts to be about 326,000 gallons, which he likened to the amount of water necessary to cover a football field a foot deep.

The YCWUA's job is to divert, transport and deliver those billions of gallons of water to local farmers through a gravity-flow open ditch delivery system.

Davis explained that the organization is the oldest diverter of Colorado River water in the Yuma area, dating back to 1907. The YCWUA was created as one of the first private nonprofit corporations in Arizona to deal with the United States Bureau of Reclamation to help develop farmland in the west, he said.

Although the Yuma Valley's farmland is not large in acreage, it is some of the best farmland in the west, Davis said.

“It's a very productive farmland, and it's multi-cropped,” he said. “In other words, we have year-round farming. The specialty of the Yuma Valley in recent decades is that in the wintertime it's the produce-producing capital of the United States. If you are anywhere in the United States during the winter months and buy any kind of celery, lettuce, cabbage or spinach, ... odds are it was grown in the Yuma Valley and was in the field just a few days before you pick it up at the supermarket, even if you live somewhere like Maine.”

Davis said that depending on the crop and the time of year, the field will require a varying amount of water.

“Typically in the wintertime we raise produce,” he said about Yuma Valley farmers. “All produce crops are fairly short-lived crops and they require frequent irrigations but not a significant amount of water. In the spring and early summer the paramount crop in the Yuma Valley is wheat, and wheat is an average consumer of water — it also requires frequent irrigations.”

Cotton, melons and sorghums also have a considerable amount of acreage in the Yuma Valley, Davis added.

He explained that water orders are placed 24 hours a day, seven days a week with the on-duty dispatcher. An order is usually satisfied within 12 to 18 hours, Davis said, noting that during the summer months that number gets pushed back because of the more frequent amount of orders that are placed.

The Yuma Valley is divided into three districts, each with its own ditchrider, who is responsible for the on-the-ground contact with the person who is ordering the water.

“The ditchrider keeps track of the time that person receives the water and the size of that delivery in cubic feet a second,” Davis said. “Typically a delivery of water is in the neighborhood of 10 to 15 cubic feet a second, so that's a volume of water that we put into that farmer's ditch during a certain period of time and then we calculate that and convert it into acre-feet. A farmer has an annual allotment of five acre-feet per acre.”

Davis added that their Supervisory Control And Data Acquisition (SCADA) system allows for the dispatcher to manipulate canal gates from their computer to move the purchased amount of water into the farmer's ditch.

“Not every gate in the SCADA system is controlled, but we have about 80 percent of our system that is accurately controlled by our keyboard,” he said, noting that they installed the system about seven years ago.

He said that mostly the smaller canals are the ones that aren't automated. Gates have to be opened manually by ditchriders for those deliveries.

In addition to delivering water to the Yuma Valley, YCWUA also delivers 40,000 acre-feet of Colorado River water to the City of Yuma to be used for municipal use and about 90,000 acre-feet also go into Mexico to be used for farming as well as for municipal use, Davis said.

Visit www.ycwua.org for more information about the YCWUA.

Sarah Womer can be reached at swomer@yumasun.com or 539-6858. Find her on Facebook at Facebook.com/YSSarahWomer or on Twitter at @YSSarahWomer.