NuFlow Alaska structurally lined over 3800 feet of steel and wood-stave pipes in a remote Alaskan village. Utilizing NuFlow’s NuTube Inversion Two Chamber Sluice they tackled the elements to restore the pipes before the annual perma-frost set in.
The City of Galena is a small village located in very remote bush area of western Alaska. Galena has no connecting road systems outside the village, so travel to and from the city is only accessible by air or water. It experiences sub-zero temperatures during winter months which freezes the ground to more than 10 feet deep. It is also the home to a former US Air Force base that has been out of service for many years. The innovative and resourceful city officials decided to transform the abandoned military base into a school campus to serve their residents. However, the sprawling campus’s sewage system is heavily corroded and in need of major repairs. The mixture of steel and wood-stave pipes have an average depth of 15-25 feet underground to prevent freezing during the long Alaskan winters. In addition, the EPA and local officials have deemed that the grounds are contaminated and therefore cannot be disrupted to replace the pipes.
The city worked with Coffman Engineers and NuFlow Certified Contractor, NuFlow Alaska, to create a solution to rehabilitate the pipe network without disrupting the land. “I recommended NuFlow Alaska because their product is able to mobilize, they could set up a work site without huge amounts of equipment. We had worked with NuFlow during an emergency situation in Galena a couple years before, so we knew they could accommodate the extremely remote location”, said Brian Gastrock, Civil Engineer and Trenchless Specialist at Coffman Engineering, Inc.
NuFlow Alaska started by conducting a thorough camera inspection of the sewer system. The inspection not only assessed the materials and severe condition of the pipes, but it gave them insight into the magnitude of the project. Working with the engineers, they created a plan to line over 3800 feet of steel and wood-stave pipes. They took special consideration to work around the extreme factors, remote location, and timing needed to complete the project before the annual perma-frost set in.
Materials and equipment were shipped via water barge. The crew arrived via a single prop plane and would live together in the old barracks for up to three months. The NuFlow technicians cleaned and jetted the entire pipe system. They transformed an open hall into a wet-out station, wetting out liners of 150 to 350 feet at a time. Using a mobile electric calibration unit by KrasoTech, they prepped the materials each day, then loaded them into an ice bath on a box truck to transport to the launch site. On site, they utilized NuFlow’s NuTube Two Chamber Sluice to invert the liners and a NuTherm heat assist unit to cure the epoxy.
“There are always hurdles to overcome when working in remote Alaska. NuFlow was able to find the unknowns, like changes in materials and diameter size, and work around them to get the job done and on time,” said Gastrock.
NuFlow Alaska concluded the project with a final video inspection for the city officials and the engineering team. They finished the project within three months, just as the summer weather began to change. The students and residents of Galena can now enjoy their campus through the long winter for many years to come.