Talk of the Town: Prescott's serious about safe yield
Recent comments on the Daily Courier Opinion Page asserted that the Arizona Department of Water Resources (ADWR) and local governments have done little to reach safe-yield by 2025 in the Prescott Active Management Area (PrAMA).
The City of Prescott disagrees. Prescott has been and continues working on its own efforts to reduce reliance on groundwater; however, local media have given very little acknowledgement to its accomplishments.
The 1980 Groundwater Management Act (GMA) created four active management areas (AMAs), including the Prescott AMA. The GMA also set a goal of reaching safe-yield of the aquifers within AMAs by 2025. Safe yield balances the amount of groundwater users withdraw from an aquifer with the amount of natural and artificial recharge that goes into the aquifer.
By state law, achieving safe-yield is ADWR's responsibility; it makes no direct delegation or apportionment of this responsibility to any water provider or user within the Prescott AMA. ADWR imposes conservation requirements on water providers, creates incentives to use and recharge recycled water, and places limits on groundwater access and use. Each measure is intended to bring the AMA closer to reaching safe-yield.
Prescott's efforts to reduce reliance on groundwater began in the 1980s, even though the Prescott AMA was not determined to be out of safe-yield until 1999. For example, in 1988, Prescott became one of the first municipalities to treat and recharge effluent to offset groundwater pumping. Prescott also sought to buy surface water rights from the Chino Valley Irrigation District in Willow and Granite Creeks, which feed into Watson and Willow Lakes, eventually adding more than 1,300 acre-feet per year of renewable surface water to its water portfolio, further reducing Prescott's dependence on groundwater.
ADWR's Third Management Plan for the Prescott AMA 2000-2010 states that achievement of safe-yield by 2025 depends on four conditions: significant water conservation by cities, towns and private water companies; reduction of groundwater use for turf and increased use of effluent; use of other renewable supplies; and Big Chino groundwater importation. ADWR further stated in 2004 that "achievement of the safe-yield goal without a source of imported water supply is doubtful, if not impossible, given groundwater requirements to meet the needs of current residents in addition to the groundwater commitments extended to pre-declaration subdivisions that are still to be built."
We have recognized the Prescott AMA's need for additional water for some time. In 1991, the Legislature granted Prescott the explicit right to import as much as 14,000 acre-feet of groundwater from the Big Chino sub-basin in exchange for facilitating the settlement of two Indian water rights settlements and transferring its allocation of Colorado River water to the City of Scottsdale.
To exercise its property rights to this water, Prescott conducted extensive hydrologic studies of the Big Chino Sub-basin, finally determining that a well field located at the Big Chino Water Ranch would provide a secure supply of groundwater for the Prescott AMA while minimizing the potential to harm the Upper Verde Springs 20 miles from the Ranch.
In 2005, the Prescott City Council also approved a resolution reserving the amount of water Prescott could import from approximately 1,100 acres of historically irrigated acreage on the Big Chino Water Ranch, equaling nearly 3,300 acre-feet per year, to augment safe-yield or to mitigate any measurable impacts to the Upper Verde from Prescott's pumping.
Recognizing the critical role conservation plays in achieving safe-yield, Prescott employs numerous water conservation measures, including a full-time coordinator, conservation incentives, and a tiered water rate structure. The city's water management policies and codes also contribute to reducing reliance on groundwater. Successful water management tools include: a conservative water allocation budget; time-of-day watering restrictions; expanded use of effluent; and a consistent meter replacement program. Prescott residents' response to these measures has resulted in a 15 percent per-person decrease in water use since 2003, even though the City's population has increased 13 percent. And, even though 8,200 housing units
have gone up since 1992, users pumped less groundwater in 2008 because of the expanded use of alternate water sources! Reduced water demand also saves money for the city and its citizens by reducing operating costs to treat and deliver water.
The City of Prescott is not the only entity working toward safe-yield. Prescott and other Prescott AMA communities belong to many state- and county-wide committees that also are joining together to try to develop solutions that will work for all water users and providers to reach safe-yield.
Our local legislators also have introduced and enacted legislation that requires development outside of AMA's to follow some of the same rules AMA communities must follow. Yavapai County has restricted the ability to develop without an assured water supply.
Achieving safe-yield is a complex long-term process. While the efforts of Prescott and other water providers have reduced per capita use, aquifer overdraft is still occurring. This results partly from the approximately 10,000 unregulated wells within the AMA. Each of these "exempt" wells may withdraw as much as 56 acre-feet per year! Prescott sent a resolution to the legislature asking the state to acknowledge its responsibility to engage well owners in the process. Until these water users are included in a safe-yield solution, it will be very difficult to achieve.
Safe-yield is important for the long-term availability of adequate, high quality water for Prescott AMA communities. Prescott remains committed to working with ADWR and other Prescott AMA parties to achieve safe-yield.
Steve Norwood is the city manager of Prescott. Contributors to this article include Rita Maguire, former director of ADWR, and Jim Holt, former director of the Prescott AMA.