Alaska Highway Major Storm Sewer Relief
Owner:City of Fort St. John
Engineer:Urban Systems
Location:Fort St. John, BC
Product Utilized:
DuroMaxx® SRPE Pipe
The Challenge
There were several challenges encountered on the project. The job location proved challenging, with low cover availability along several sections of the pipe route. The project also had a very tight construction window; therefore, installation had to proceed as quickly as possible. Finally, the proposed solution needed to provide both durability and maximum service life.
The Solution
Armtec proposed the installation of 874 metres of 2,438 mm (96 in) and 155 metres of 2,134 mm (84 in) nominal diameter DuroMaxx Steel Reinforced Polyethylene (SRPE) pipe to provide storm sewer relief to the city’s existing system which was undersized for peak storm events. The low available cover required a relief sewer design optimized for both size and hydraulic capacity. The wall thickness of 2,438 mm Duromaxx pipe is approximately 15% less than the thickness of equivalent concrete pipe with the same internal diameter. This feature allowed Duromaxx to fit within the vertical profile available, where other pipe types would not. In order to accelerate installation, the pipe was welded from the interior allowing the contractor to backfill ahead of the welding crew. The long Duromaxx pipe lengths also reduced the number of joint connections compared to concrete pipe, allowing construction to proceed quickly and efficiently. Finally, DuroMaxx pipe’s lighter weight made it easier to handle with less heavy equipment and labour costs.
