The Prescott city Council is seeking a hydrological study for northern Williamson Valley as a possible alternative to pumping from the Big Chino aquifer near Paulden.
Just two weeks ago, the Prescott City Council heard a preliminary report on the design of the pipeline that would bring water to the tri-city area from the Big Chino aquifer in Paulden. In a unanimous vote last week, the council agreed to allow the engineering company to proceed with the $500,000 design.
Then, in a surprise move, the city announced this week that it has gone out for proposals for a hydrological study “in the far northern reaches of Williamson Valley.”
City Manager Larry Asaro said the new study would determine how much water lies under the ground in that area to help the city decide if that might be a better location to get its alternative water. Asaro added that the study area is “in the vicinity of the Las Vegas Ranch.”
The new move does not mean that the city is abandoning the Paulden option, but it could bring the project into question in the future. Asaro said the city will proceed with the design of the Paulden pipeline and look at it – along with the results of the Williamson Valley hydrological study – in the spring to determine how the city should proceed.
In the meantime, Asaro said, “We can’t give up the Big Chino at Paulden, because that’s a known entity.”
But he acknowledged that the possibility exists that the city could back away from the Paulden option at some point in the future. “Yes, we could be out some money on this,” he said. “That’s probably the biggest concern we have right now.”
Like the Paulden area, the Las Vegas Ranch area is within the bounds of the Big Chino basin. That would qualify it as a source of alternative water for the city, because it is outside the aquifer that the city currently takes its groundwater from.
In 1998, the Arizona Department of Water Resources declared that the Prescott Active Management Area (AMA) was in a state of groundwater mining, which meant the area was taking more water out of the ground than it was putting back in.
The groundwater mining declaration restricted the amount of water the area can take from the ground. That led the city to look to the Big Chino aquifer to the north to find water from outside its own aquifer.
Although the Paulden pipeline plan has faced considerable opposition from the Verde Valley, Prescott City Council members appeared resolute in their plans to build the pipeline.
But Asaro allowed on Tuesday that the council has been quietly discussing the possibility of getting water from elsewhere for weeks now.
Already, the city has received proposals from four firms interested in doing the new hydrological study. Asaro was uncertain exactly how much the study would cost, but he estimated it would be in the $50,000-to-$100,000 range.
The matter likely will be on the City Council agenda on Dec. 18 for official consideration of the proposals. That would be the first time the council has discussed the possibility in a public session. Asaro acknowledged that much of the discussion leading up to this point has occurred in closed-door executive sessions of the City Council, as well as at a staff level.
“A couple of months ago, former Mayor (Sam) Steiger brought up the fact that parties are interested in doing a hydrological study” in the Las Vegas Ranch area, Asaro said. “We knew all along that the shape of the Big Chino (aquifer) would allow for access at different points.”
Alternative water has been on the council’s executive session agendas from time to time over the past several months. The Arizona Open Meeting Law allows the council to discuss “the purchase or lease of real property” in private, as well as consultation for legal advice with the city attorney.
In October, the council approved a retainer agreement with Tucson water attorney Carlos Ronstadt for as much as $50,000 to handle water-related issues. Asaro said this week that Ronstadt is helping the city with the Las Vegas Ranch water plans.
City Attorney John Moffitt said the city followed its normal procedures when it went out for proposals for the study without first getting a public City Council vote on the matter.
“It would be uncommon for the City Council to authorize an RFP,” Moffitt said. Rather, he said, city staff normally authorizes the RFPs, and then takes the results to the City Council for approval or rejection.
In its press release, the city referred to the Williamson Valley plan as a potentially “environmentally friendly” option for alternative water. City officials say the plan may be more palatable to Verde Valley officials, because it would take the water from a point in the Big Chino aquifer that is farther from the Verde River headwaters than is the Paulden option.
Councilman Robert Behnke, who serves on the Yavapai County Water Advisory Committee with Verde Valley officials, said a number of questions still remain.
“The hydrological study will tell us a lot,” he said. “I suspect that (pumping from the Williamson Valley area) will have little or no impact on the Verde River.”
New Mayor Rowle Simmons said city officials informed him early on of the plan to go out for proposals for the hydrological study.
But Simmons declined to discuss the details of the plan. “Unfortunately, this is all premature,” Simmons said of the city’s Tuesday announcement. “We’re not prepared to discuss some of the possible options.”
Because word of the plan began to circulate in the community, Simmons said, the city decided to release the information this week.
Contact Cindy Barks at firstname.lastname@example.org