Scottsdale pipeline seeks to diversify municipal water portfolio
By Terrance Thornton | Digital Free Press
Scottsdale is commencing a critical phase of the envisaged aquifer storage and recovery water well pipeline.
Scottsdale City Council early last week approved an $8,530,423 construction manager at-risk contract with MGC Contractors for the construction of Package 1 of the Scottsdale Water aquifer storage and recovery well pipeline.
“As part of Scottsdale’s long-term commitment to increase local groundwater recharge within the city by 2024, Scottsdale is in the process of drilling four aquifer storage and recovery wells (54C,159,160, and 161) at strategic locations over the next several years,” said Brad Walldorf, project manager at Scottsdale Capital Projects. “These new wells will both recharge the existing aquifer with water received from the city’s potable water distribution system and recover water from the aquifer for treatment at the city’s existing facilities.”
Scottsdale City Council, part of its consent agenda, unanimously approved the $8 million contract Monday, Nov. 14, at City Hall, 3939 N. Drinkwater Blvd.
In his report to City Council, Mr. Walldorf outlined the phased process of creating the now-approved pipeline, which includes two phases that are drilling and equipping.
“This program has been forecasted to have multiple GMPs, two for each well and at least two pipelines to connect wells 159, 160 and 161 to the water campus for processing groundwater and recovering water back into the aquifer,” Mr. Walldorf wrote in his report.
“Wells 160 and 161 will have a shared pipeline for most of their connections to the water campus, which is broken up into multiple construction packages. The purpose of the action is to authorize the ‘Guaranteed Maximum Price’ (GMP4) contract award for the construction phase of services for installing the Package 1 Pipeline for the city of Scottsdale’s aquifer storage and recovery wells 160 and 161.”
In all, Scottsdale is laying 6,300 feet of 16- by-24-inch ductile iron pipe to connect the man-made underground water recharge project, records show.
“This includes the installation of over 6,300 feet of fiber optic, 7,786 square yards of pavement removal and replacement,” Mr. Walldorf pointed out in his report.
A year’s long Scottsdale water endeavor
While the million-dollar contract was approved on consent, Mr. Walldorf explains the meeting agenda item is the culmination of several internal steps toward water conservation at the Scottsdale Water department.
“On April 15, 2019, council approved amendments to the organization strategic plan. The ‘Seek Sustainability’ section included the following objective: Implement an enhanced water recharge program by constructing four new aquifer storage and recovery wells,” he said, pointing out a request for qualifications when out November 2019 for the complex, long-standing project.
“The city received five responses by the Dec. 18, 2019 deadline,” he said. “A panel of six evaluators, which included a registered engineer and a licensed contractor, selected the top three responses, and conducted interviews with the three firms, evaluated their responses, and selected MGC Contractors, Inc. to be the CMAR for this project.”
Emboldened through resolution No. 11789, Scottsdale has approved the following:
- On Sept. 22, 2020, City Council approved (GMPl $ 1,471,172.04) Phase 1 Drilling of Aquifer Storage and Recovery Well 54C.
- On Aug. 26, 2021,City Council approved (GMP2 $ 5,950,104.04) Phase 1 Drilling of Aquifer Storage and Recovery Wells 159,160, and 161.
- On Jan. 11, 2022, City Council approved (GMP3 $ 9,446,391.35) Phase 2 Equipping of Aquifer Storage and Recovery Well 54C.
Mr. Walldorf reports this project is a critical step in addressing the increasing water needs of the community of Scottsdale.
“This project will address the increasing water demands for the future, diversify our water portfolio and will allow the city to recharge our aquifers with the Central Arizona Project allocation while seasonal water demand is low,” he said.