First the backhoes start tearing up the street.
Now the Payson Town Council is ready to approve a $1.6 million contract to come up with the final designs for a new water treatment plant.
Looks like they really are going to build the $40 million C.C. Cragin Pipeline, to ensure Payson becomes one of the few communities in the state with an ample future water supply.
The award of a design contract to Sunrise Engineering will dominate the Thursday council agenda. Sunrise was the only firm to complete a bid on the complex job of designing the microfiltration plant that will treat 3,000 acre-feet annually to meet drinking water standards. However, the bid hardly came as a surprise — since Sunrise has done the preliminary designs on most of the components of the project and has teamed with Tetra Tech, which has provided engineering services for a host of town projects.
The C.C. Cragin Pipeline in 2014 will more than double Payson’s water supply, providing enough water for a population of some 38,000. The town’s success after decades of effort in securing rights to the Blue Ridge Reservoir (now C.C. Cragin Reservoir) water was the key role in Payson’s ability to seek to attract a university campus and various spinoff businesses. Advocates hope the arrival of the water will help foster new growth. The town will have so much extra water in the early years that it hopes to actually inject water into its well system to replenish the depleted water table.
The $7.5 million water filtration plant planned for a patch of juniper and pinyon pines next door to Mesa del Caballo remains perhaps the most critical new facility when it comes to injecting the Blue Ridge water into the town’s existing system.
The design contract will include building the water treatment plant and the complex systems it contains. That includes:
• Designing the array of tubes with microscopic holes to filter sediment, algae and bacteria from the Blue Ridge Reservoir, pristine, rain and snowmelt taken from near the bottom of the lake.
• Building a concrete storage tank for the Blue Ridge water, to control the rate at which it’s fed into the town’s existing water system, which relies on pumping water out of wells into a series of existing storage tanks.
• Designing a hydroelectric generator to produce electricity from the pressure of water surging through the pipeline on the 17-mile, mostly downhill run from Washington Park, down Houston Mesa Road to the new treatment plant near the Shoofly Ruins.
• Designing control systems to use that hydroelectric power to run the system — with the excess sold to Arizona Public Service (APS). The town is still trying to determine whether it will get a better deal selling the excess electricity directly to APS or trying the system.
• Designing systems to make sure that the water doesn’t come out so pure and low in minerals that it will dissolve deposits that have built up in the existing system. Payson’s ground water has a high mineral content, which means that the insides of pipes can become coated with minerals. The ultra-pure Blue Ridge water could dissolve those deposits and result in sludge sputtering from water faucets if it’s not buffered chemically before it’s released into the systems.
• Designing the connections and control features to inject Blue Ridge water into the town’s existing network of wells and storage tanks. Already, contractors are putting in pipes to connect the until-now separate networks of pipes connected to different combinations of wells. The new system will provide the whole town with Blue Ridge water during certain times of the year. Since Blue Ridge will deliver 3,000 acre-feet annually while the town uses only 1,800 acre-feet, roughly a third of the Blue Ridge water will go back down into existing wells to replenish the water table. During the winter, the town will revert to relying on well water, when snows up on the Rim shut down the Blue Ridge pipeline.
• Designing the connection between the treatment plant and the Northern Gila County Sanitary District’s system. The microfiltration tubes will remove solids, algae and bacteria from the relatively clean water. The plant will generate “sludge” thick with the materials removed from the water. The town has to figure out what to do with this wastewater. Most will probably go through the Northern Gila County Sanitary District’s treatment plant, but some of the water could provide things like golf course irrigation and an unspecified “water feature,” according to Sunrise’s project description packet.
Sunrise designed what amounts to the rough draft of the system in accord with an earlier contract. The firm’s bid stressed that intimate knowledge of the system. Moreover, Sunrise has designed many systems that have different elements of the complex Payson system, although has rarely had a chance to put them all together at once.
“Sunrise Engineering has completed countless water resource projects through our 34 years of business,” the company wrote in the bid documents. “While this fact alone does not separate us from the crowd, our unique combination of project experience certainly does. Specifically, we have completed a number of Membrane Filtration Plants throughout the southwestern states — this experience is unique because this type of filtration is a newer technology that is not yet commonplace. We have also been involved on a high volume of Concrete Tank Design projects, a tank type not commonly utilized throughout Arizona.”