Do New Homes Hurt the Verde River?

Yes. Every new home consumes groundwater, the source for life-sustaining perennial flow in the Verde River – the only surviving living river in Arizona.

Since Arizona’s statehood, groundwater pumping and surface water diversions have severely impacted major groundwater basins and seriously degraded five of Arizona’s major perennial rivers: the Colorado, Gila, Salt, Santa Cruz, and much of the San Pedro. Only the Verde River survives, supporting a rich diversity of wildlife - including sixteen species listed under the Endangered Species Act, plus many other benefits (see “Ten Reasons to Protect the Verde”).

Despite its importance, we are drying up the Verde River. In 2018 the annual flow volume was 61% of the estimated flow in 1940. Some of that decline is due to persistent drought, but groundwater pumping takes a huge toll. Every gallon of groundwater we pump is one less gallon for the river.

State water law fails to protect rivers and springs. Instead it facilitates unsustainable growth and development by pumping too much groundwater. As a result, in the Prescott Active Management Area the groundwater overdraft is large and growing, aquifer water levels are dropping, and Del Rio Springs, the historical headwaters of the Verde River, is now at 10% of its former flow. 

Meanwhile, local officials claim that they are only obeying Arizona water law. Prescott officials claim that new water policies will benefit the aquifer, but at least 25% of the water delivered to every new home is lost and cannot be recharged. Although Prescott and Prescott Valley recharge treated wastewater, they recover that water and use it support new housing development; there is no benefit to the aquifer. All new housing should have net-zero impact on the aquifer.

Groundwater pumping from the Big Chino aquifer (underlying Williamson Valley, Paulden, and the Big Chino Valley) is even more serious. Over 80% of the Verde River base flow comes from groundwater in the Big Chino aquifer. In the Big Chino, population growth, agricultural irrigation, and groundwater exports to Prescott and Prescott Valley threaten to dry up the Verde. Arizona water law ignores these threats.

Domestic wells in Paulden already reduce the river flow, and that impact will increase as the community grows. The Board of Supervisors should control this threat.

Arizona law permits a farmer to irrigate in the Big Chino using groundwater. The Arizona Legislature has failed to control this threat.

Arizona water law authorizes Prescott and Prescott Valley to export Big Chino groundwater using the planned Big Chino Pipeline - more than enough to dry the Verde River. Prescott and Prescott Valley have promised to offset the effects of their pumping on the river, but no mitigation plans have been released.

We can protect the Verde River, but it’s up to us. The state government won't help. County and municipal officials need to work together, acknowledge the problem and plan to invest in major conservation programs and investigate alternatives.

As citizens, we can minimize outdoor water use, install efficient appliances, and let our officials know that current policies are unsustainable and unacceptable.

Most importantly, vote for candidates who support a secure water future and a flowing Verde River.

Updated September 20, 2021