Missouri River water main crossing complete and in service; Sun River crossing nearly complete
The new 24-inch water main crossing under the Missouri River is complete.
Public Works Director Jim Rearden told City Commissioners earlier this month that the crossing had passed all bacteriological and pressure tests and was put into service Nov. 25.
The Sun River Crossing is nearly complete and was tied in on the north end and pressure tested. But the south end couldn’t be tied into the water system until the 24-inch main under the Missouri was completed since tying in the Sun River line would require taking the line that serves Gore Hill and the airport out of service.
Rearden said that with the weather conditions, the Sun River crossing likely wouldn’t be completed until spring since tying into the water system on the south end also requires getting into Alder Drive to do some digging.
The project was also recently named the winner of a 2019 American Council of Engineering Companies Water Resources Honor Award.
Local companies AE2S and TD&H Engineering worked on the project, among others.
The City Commission approved the $5.5 million contract with HDD Company during their July 16 meeting. The city received three bids for the project and HDD was the low bidder.
The project consists of installing water main utilizing both horizontal directional drill and open-cut methods of installation.
Using the HDD method, the company will install about 3,600 lineal feet of fused PVC 24- inch DR18 pipe under the Missouri River; 300 lineal feet of 42-inch steel casing pipe under BNSF railroad right-of-way; and 1,600 lineal feet of fused PVC 20-inch DR18 pipe under the Sun River. The open-cut method will be used to install about 1,600 lineal feet of 24-inch pipe and 1,200 lineal feet of 20-inch pipe.
“These two new crossings have been part of the long range master plan for the City of Great Falls water system since at least 2006. Funding has now become available to complete them,” Rearden said in a summertime press release. “The two new river crossings will substantially increase the reliability of our system by providing redundancy to serve our citizens.”
As part of the project, Meadowlark Park was closed in order to install new 24-inch piping from Alder Drive to Fox Farm Road. The park will also be used to accommodate a work site for the drilling operation and staging area for assembling the pipe needed to cross under Meadowlark County Club Golf Course and the Missouri River.
AE2S provided technical design and construction support for the directional boring of large diameter PVC pipelines of significant length, including the preparation of the specifications, contractor qualification criteria, QA/QC, shop drawing review, etc.
City parks were disrupted during the construction and will be repaired.
City Parks Supervisor Lonnie Dalke told The Electric in October that when construction is finished, depending partly on the weather, the contractor will sod Meadowlark Park and seed Verde Park. Irrigation systems will be repaired in both parks, he said.