Tuesday, February 19, 2019

CAP Water Restrictions Should Have Minimal Impact On Oro Valley

The Arizona Department of Water Resources (ADWR) has an agreed upon plan to reduce Arizona's annual allotment of Colorado River Water from Lake Meade.  Under the plan, various classes of CAP water users be allotted less water.  One class of users, Pinal County farmers, will be hard hit. Residential and industrial users, like Oro Valley, will see minimal change in their annual CAP water allotment.

CAP water restrictions: Minimal impact on the Oro Valley
The potential reductions in CAP water availability will be trigged by the level of water in Lake Meade. The level that triggers the reduction is expected to occur in several years.

When this happens, the reduction in CAP water should have minimal impact on Oro Valley, according to Oro Valley Water Director Peter Abraham. "I'm planning for a reduction in CAP water," Abraham told us in during our interview with him last week.

Source: Town of Oro Valley
The reason that the ADWR plan will have minimal impact on Oro Valley is that the town now maintains its sustainable water supply by using 72% of its CAP water allotment. The state's plan reduces Oro Valley's allotment to 93% of the current CAP water allotment.  Oro Valley will use less than 80% of this new, lower allotment. Thus, Oro Valley's wells will be replenished in the same quantities tomorrow as they are today.

The impact Oro Valley will see is a reduction in the credits, called storage credits, the town gets for the CAP water it does use. That's currently about 2,200 acre feet (AF) per year. Under the ADWR plan, Oro Valley will get credit fewer storage credit, about 1,500AF.  That's not much of an impact, even in the long run. Oro Valley already has 22,000AF storage credits on the books!

No impact from Pinal County farmers
We also leaned from Abraham that Pinal County farmers draw from an aquifer that is not connected in any material way to the aquifer that supports our groundwater supply. There will be no impact on our water supply even if the Pinal County farmers drain their wells dry.

CAP water will cost more
The problem for Oro Valley residents, Abraham observed, "...is that water is going to be more expensive... The same fixed cost. The same infrastructure." Less water taken means greater cost per AF.
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