BY: Warren Tenney

Water Security is Vital for Housing and our Economy

Published May 07, 2024

Last week, in an op-ed, two Arizona lawmakers argued that passing HB 2589, which would allow several groundwater-dependent housing developments on the outskirts of the Valley and in the Pinal area to be built, is a “common-sense” water policy. Yet, absent from their reasoning, are how the consequences of passing this legislation could endanger the water protections homeowners and businesses enjoy. HB 2589 circumvents the primary tenant of Arizona’s 100-year Assured Water Supply Program, “water first, then development,” upon which Arizona’s economic success has been and continues to be built. 

Last June, the Arizona Department of Water Resources (ADWR) released its updated model for the Phoenix area, which projected that available groundwater would be unable to keep pace with demands over the next 100 years. This projection of nearly 4.9 million acre-feet of unmet demand for groundwater supplies echoed a 2019 model for the Pinal area that projected 8.1 million acre-feet of unmet demand. Since Arizona law requires the consumer protection of a 100-year water supply for new single-family homes in these areas, ADWR halted the development of new subdivisions solely dependent on groundwater outside the water providers' service areas that have shown a 100-year assured water supply. HB 2589 would override that moratorium and, in turn, erode our water security.

We cannot ignore the hydrologic realities when considering the long-term consequences of water legislation. Proponents of HB 2589 are technically correct that this bill requires these unbuilt developments to agree to reduce their proposed water demands by 15%. However, that is still 15% of 158,000 acre-feet and 85,000 acre-feet of new annual pumping in the Phoenix- and Pinal-area, respectively. Put simply, the 15% reduction will have little impact on the massive new burden these developments will place on already stressed aquifers.  

Proponents of HB 2589 have stated the old argument that any pumping for these new subdivisions won’t matter because it will be replenished by the Central Arizona Groundwater Replenishment District (CAGRD). This claim omits facts and fails to ask critical questions. The CAGRD currently replenishes about 35,000 acre-feet of pumping annually. Yet, the subdivisions allowed by HB 2589 would increase that current obligation by almost six. CAGRD would have to acquire additional water supplies – such as groundwater from rural Arizona or Colorado River water from on-river users, in order to meet these new obligations and construct new replenishment projects. All of this would dramatically increase the assessment paid by current and future residents to CAGRD for the costs of acquiring, transporting, and replenishing these expensive water supplies. This assessment, which CAGRD homeowners pay on top of their water bill, has already increased by 167% over the past 15 years. If HB 2589 is signed into law, that assessment will only continue to increase for all CAGRD homeowners – primarily in the far southwest and west areas of this Valley – not just those who live in the new homes that this bill would allow to be built.

Last week’s op-ed failed to mention that homebuilding can continue within the service areas of water providers designated as having an assured water supply. These providers have demonstrated to ADWR that they have enough water supplies to meet their current and future demands over the next 100 years. As part of a designation, these providers also agree to limit their groundwater pumping. There are at least 185,000 acres of developable land within the service areas of the 15 designated providers in the Phoenix area, enough to support over half a million new homes, which doesn’t even consider other housing opportunities.

No home today will have value in the future if it lacks water. Legislation that raises questions about Arizona’s willingness to maintain management practices that guarantee water security will undermine our economy today and for the future. Water security drives our entire economy.

A better approach for enabling growth in communities on the edges of the Valley is to encourage the water providers that serve those communities to obtain a Designation of 100-year Assured Water Supply. ADWR is actively working with stakeholders on a way for more water providers to become designated in an effort to shift development away from reliance on finite groundwater and towards other, more renewable supplies. This alternative pathway to a designation aims to ensure that housing and commercial development can continue in the service areas of municipal providers that are willing to invest in new alternative water supplies and the infrastructure needed to make those supplies available for their customers. This sustainable approach, which sharply contrasts with the continued growth on groundwater under HB 2589, would be a true win-win for everyone.

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For 55 years, the Arizona Municipal Water Users Association has helped protect our member cities' ability to provide their communities with assured, safe, and sustainable water supplies. For more information, visit .