Many Western states are developing water plans. How can they learn from Arizona’s experience?
Water planning is big news in the West these days. In Texas, Kansas, Colorado, and California, statewide water planning is underway or has recently been completed. On a larger scale, the 7 states and 10 tribes of the Colorado River Basin are also in the throes of a multi-year water planning effort. Arizona, on the other hand, began this process back in 1980, when the Groundwater Management Act was passed. Although plans vary from state to state, all have some common components. There are several critical steps in the water planning process:
- Define the planning area. This can range from a single hydrologic basin or a large political jurisdiction that crosses hydrologic boundaries.
- Inventory existing supplies and demands and, in some cases, establish monitoring protocols to collect critical data. This inventory should consider water quality in the context of potential uses.
- Define the management goal (if the law has not already done so) and, from this baseline, establish a planning horizon for making projections.
- Determine how to bridge the supply-demand gap and meet the management goal.
Because projections are likely to show water demand exceeding supply in the future, this final step is the most difficult. Strategies can include a combination of conservation, reuse, growth management, operational changes, ag-to-urban water transfers, and possibly importation. Omitting this step — a common practice — produces “a call to action” rather than an actual “plan,” as reflected in the progress to date on the Colorado River Basin study.
In California, just as in Arizona’s most populous basins, the management goal is essentially to balance supply and demand and stop mining groundwater. California’s new water management law sets an aggressive timeline: Critically overdrafted basins must adopt “sustainability plans” by 2020 and achieve “sustainability” by 2040. In contrast, Arizona law allowed 45 years to reach this goal in most AMAs; after 35 years, several areas have already reached “safe yield” and the others are closing in on this goal. Arizona’s long planning horizon made it possible to design and invest in successful strategies to replace groundwater pumping, including building the infrastructure for using Colorado River water and effluent. Yet as we reach the end of this long period, we’re finding that the future holds new challenges — and perhaps new priorities. These challenges include growing populations, locally declining groundwater tables even if the AMA as a whole is in balance, impending shortages on the Colorado River, water quality issues, and the need to maintain water-dependent ecosystems.
In addition to providing a road map for balancing supply and demand, statewide water planning offers other important benefits. Despite its cost, difficulty, and high visibility, the process not only highlights the value of water but it also invests stakeholders in the solutions. Water planning is an ongoing process and other states can learn from Arizona’s experience.