Kathleen Ferris

AZ I See It

The 1980 Groundwater Management Act fixed a problem

In 1993%2C lawmakers created an exception that threatens the act's effectiveness

Sustainable water supplies should be established in advance of new development

In 1978, swindler Ned Warren was convicted of 20 counts of fraud for selling land in Arizona without access to water. Two years later, the drafters of the Arizona Groundwater Management Act put an end to that practice by requiring an "assured water supply" in advance of selling subdivision lots.

In 1980, an assured water supply meant a renewable surface water supply, such as Central Arizona Project water from the Colorado River or water from the Salt and Verde rivers. It did not mean groundwater. The Groundwater Management Act aims to halt the overuse of groundwater that plagued the state for decades.

The requirement to use renewable supplies encouraged cities to make investments in surface-water treatment plants and to store excess surface water underground for use in times of surface-water shortages. It drove them to clean their customers' wastewater so that it could be used instead of drinking water to irrigate turf in parks and on golf courses, and to restore riparian habitats.

Thirty-four years after passage of the act, major cities in the Phoenix area rely on groundwater for only 7 percent of their water, and they can boast of redundant, stable and secure water supplies. Take a look at California, where landowners are racing to drill ever-deeper wells at the cost of $250,000 each, and you see the nightmare central Arizona would be in without the Groundwater Management Act.

But there were some interest groups that did not like the assured water supply restrictions on groundwater pumping. So, in 1993, the Arizona Legislature created an exception that allows houses to be built on raw desert land and their owners to use groundwater on the assumption that the government will purchase water supplies to replenish groundwater that is pumped. The government agency in this case is the same entity that operates CAP.

These new desert developments are permitted to use groundwater, but pumping this resource creates problems for homeowners and others.

Overpumping groundwater causes land subsidence — the earth sinks. Shifting ground can crack foundations and damage buildings and roads. Energy and maintenance costs go up as groundwater is pumped from deeper depths. Groundwater quality may worsen, resulting in even higher costs.

CAP is not required to replenish in the areas where groundwater is pumped. Inevitably, the groundwater will run out. Who will rescue these homeowners if groundwater is no longer usable or available?

It is cheaper to develop desert land and use groundwater, so the 1993 exception to the assured water supply requirement is now the major vehicle for residential growth. CAP has the obligation to replenish for 100 years the groundwater pumped for 1,094 subdivisions, about 264,000 houses.

This obligation will continue to grow because CAP lacks authority to say no to new subdivisions. Drought and shortages of Colorado River water will increase competition for water supplies that can be purchased for replenishment. Subdivision developers are not required to pay the full cost of the water needed for replenishment and, ultimately, homebuyers will foot the bill for the groundwater they use and for replenishment water.

Today, CAP is expected to approve a plan of operation for the next 10 years to meet its expected replenishment obligations. The Arizona Municipal Water Users Association believes the plan falls short of mitigating the risks posed by continued growth before renewable supplies are in hand.

We need to get back to the model envisioned by the 1980 Groundwater Management Act, where sustainable water supplies are developed in advance of growth. Unfortunately, it appears that changes to state law will be necessary to ensure this result.

Kathleen Ferris is executive director of the Arizona Municipal Water Users Association.