Column: Not meeting safe yield holds consequences
Every year, wells in the Prescott Active Management Area (PAMA) pump out more water than area water users and nature recharge.
Our aquifer is out of safe yield. Arizona defines safe yield as a groundwater management goal that seeks to achieve and maintain a long-term balance between withdrawals and natural and artificial recharge. The state would like us to be in safe yield by 2025; however, the law provides no regulatory programs for achievement or penalties for failure. Safe yield is only a goal, and achievement is voluntary.
We can't overdraft out aquifer indefinitely. If we don't achieve safe yield we will have severe problems. As the water levels continue to decline, wells will go dry, streams will disappear, the soil structure will change and the aquifer will not be able to deliver enough water for our communities. Property values and population will decline.
These problems are not immediate, but it is their lack of immediacy that enables our officials to avoid the difficult decisions needed to achieve safe yield. Although it would be preferable for our communities voluntarily to develop and implement a plan to achieve safe yield, their track record is poor. The state needs to consider establishing consequences.
With our aquifer in overdraft, the state requires that new subdivisions receive "alternative water," which is any water other than PAMA groundwater. This restriction, however, does not help eliminate the current overdraft. Furthermore, it does not apply to exempt wells or commercial and industrial development, or satisfy additional demand from the many previously approved, but unbuilt, plats in the region. These expected increases in groundwater use and the use of alternative water for new subdivisions can continue beyond 2025 even if the area has not achieved safe yield.
The state should consider limiting the number of new subdivisions and exempt wells and tying their approval to a schedule of milestones including incremental reductions in the overdraft between now and 2025. This would provide a strong incentive for all the users to develop a joint plan specifying how much groundwater each can pump and safely how much water each must dedicate to safe yield.
Currently, local governments may obtain a credit for effluent they recharge to the aquifer. This credit allows localities to pump additional water from the ground, and use it for new subdivisions. The state could require that localities recharge all new effluent permanently where local entities have not achieved safe yield.
This requirement would be similar to a provision of Proposition 400 that the City of Prescott voters approved overwhelmingly in 2005. Permanent recharge of effluent would help us reach safe yield.
If we are going to achieve safe yield before we experience severe hardships, we need regulatory consequences. The Arizona Department of Water Resources should take the lead in establishing new regulations. I have presented some ideas, but it should consider others as well.
(John Zambrano is a retired environmental engineer and vice-president of the Citizens Water Advocacy Group.)