Tolt Pipeline No. 1 Rehabilitation

Project Summary

This project included the rehabilitation of 2,500 linear feet of the Tolt Pipeline No. 1 using 54-inch HDPE pipe installed by slip-lining. The scope included connections to an existing 66-inch pipeline, installation of blowoff valves and chambers, installing an access port and air release chamber, and associated restoration.



Duvall, Washington


City of Seattle

Contract Amount

4.4 million


July - October 2022

Project Highlights

The majority of work was performed under live power lines, and the construction team was committed to strong safety culture and behavior, taking safety into account at every move. This project exemplified a great partnership with the City.