By Suzanne Adams-Ockrassa for Pinal Central
The long, hot summer with few monsoon rains continues to remind Pinal County residents, and especially farmers and ranchers, about the preciousness of water in a desert climate.
This year, ranchers are on the edge of having to make a decision on whether to buy feed and haul water for their animals, said Richie Kennedy, president of the Pinal County Farm Bureau.
The future of both residential and industrial development and agriculture in Pinal County depends on the availability of water, but no one is really sure how much water is available.
Pinal County agriculture gets a large amount of its water from the Central Arizona Project but that source may be limited. Under a 2004 settlement, all CAP water for Pinal County farmers is supposed to end in 2030, but the new Lower Basin Drought Contingency Plan that was signed in 2019 may reduce that supply of Colorado River water faster than farmers expected.
The Drought Contingency Plan is an agreement between Arizona, California and Nevada to reduce the amount of water taken from Lake Mead if the level in the lake falls below a certain level, such as during a drought. The first in line to take a cut in CAP water supply should Lake Mead fall below that level would be Pinal County farmers.
The U.S. Bureau of Reclamation’s April 24-month study projects that Lake Mead will likely stay in the Tier Zero of the Drought Contingency Plan’s water restrictions in 2021 and 2022. That tier requires Arizona to take a 192K acre-foot reduction in its 2.8M acre-foot allotment of Colorado River water. Those reductions will fall entirely on CAP supplies, according to the Arizona Department of Water Resources.
As part of the DCP agreement, Arizona agreed to allow irrigation districts to pump more groundwater for farmers to help replace some of the CAP water.
But ADWR released a new groundwater model for the Pinal Active Management Area last year that shows that there may not be enough groundwater to sustain as much residential development in the area as was believed earlier.
The ADWR model estimates that in 100 years, the area will need 80M acre-feet of water to meet demand; it projects that the area will fall 8 million acre-feet short of that need.
Local water users, including farmers, municipal water suppliers and developers have questioned some of the calculations behind ADWR’s new groundwater model.
There are areas in the Pinal AMA that have issues with access to groundwater, Kennedy said. But there are also other areas that have no problem with groundwater access. ADWR’s model seems to apply that groundwater access problem to every well in the AMA. It doesn’t take into account that a farmer, irrigation district or municipal well owner might just drill the well deeper or drill an entirely new well.
It also doesn’t seem to take into account that the cost of water and the cost of electricity to pump it is an incentive that pushes farmers to become more efficient, he said. For example, a farmer may stop irrigating a field that has a crop that is struggling because of drought or something else, because he knows he’s not going to get a good price for that weak crop.
Read more at Pinal Central.