COTTONWOOD - The Yavapai County Water Advisory Committee Wednesday approved baseline population estimates through the year 2050 that scientists will run through a computer model of the region's groundwater system.
The Yavapai County process is "groundbreaking," contractor Hoyt Johnson told the committee, because of its detail and cooperative effort between various jurisdictions.
For example, in the water-use section he still is finalizing, Johnson is plugging in thousands of residential wells in specific groundwater sub-basins, based on existing zoning and roads in each area. Local government officials estimated how much water each type of well would use.
Local government officials and Johnson hope to finish water-use estimates by early April and get the work to the U.S. Geological Survey so that agency can run the figures in a groundwater computer model that covers a huge swath of Arizona, including the northeast quadrant and on south to Greenlee County.
That means the water committee might have to approve the final water figures via e-mail since it doesn't plan to meet again until April.
Local governments estimate the population of the Verde River Basin within Yavapai County will be 529,717 by 2050, compared to 209,266 today.
However, officials noted, that's only a best guess.
Local governments have used other numbers for other purposes.
For example, the water committee is calling the new growth scenario the "community general plan" scenario.
However, the general plans for Yavapai County, Prescott and Prescott Valley all contain population growth estimates much less than the water committee's estimates.
On the other end of the spectrum, the Central Yavapai Metropolitan Planning Organization (CYMPO) estimated that the four Prescott-area municipalities and surrounding rural land would be home to 439,389 people by the year 2030.
Yet the water committee estimates that only 429,542 people will live in a much larger area by 2030, an area that adds the entire Verde River Basin within the county (Verde Valley, Big Chino Valley, Paulden, etc.).
Prescott Valley Town Councilman Mike Flannery defended that particular disparity Wednesday, saying the federal government won't let CYMPO attach growth constraints to its study.
While some of the municipalities made their own population estimates, the county and other municipalities used Arizona Department of Economic Security estimates, which history has proven to be consistently low.
The figures show Chino Valley currently is by far the largest municipality in the county in geographic area at 32,661 acres. It has completed several large annexations of ranchlands in recent years. Prescott Valley is the second-largest at 21,544 acres, followed by Prescott at 16,479 acres.
Yet Prescott is the largest community in population, more than three times the population of Chino Valley.
Yavapai County Supervisor Chip Davis expressed shock at the number of homes and wells plugged into the Big Chino Valley north of Prescott.
Government officials decided to include two large proposed developments in the Big Chino Valley, on the Yavapai Ranch (45,000 people) and the CV/CF Ranch (20,000 residents).
Local government officials avoided making other types of assumptions in the population growth scenarios.
For example, they decided to leave state trust lands undeveloped even though they technically are available for development.
"We didn't want to assume the role of planners," explained John Munderloh, water resources manager for Prescott Valley.
In the future, the committee plans to submit other potential population and water growth scenarios for the groundwater model, such as scenarios that estimate a faster growth rate and/or water conservation.
Contact the reporter at jdodder@prescottaz.com
Reader Comments
Posted: Saturday, March 22, 2008
Article comment by:
Tom Steele
Clearly growth SHOULD be limited to a sustainable water supply. However, each of our political entities HAS a water expert and that is where the crunch occures. With growth important for jobs and the Land Barons, the population of regular folks better keep an eye open. Remember we are taking about 13,500 ac/ft of water a year out of our aquifer that mother nature is not replacing. How can Yavapai County double its population?
