City of Coos Bay, OR

08/21/2019 | News release | Distributed by Public on 08/21/2019 20:42

Horizontal Directional Drilling Under the Bay

The City of Coos Bay is installing a new force main that will take all the sanitary sewer flows from Eastside and transfer them directly to a Pump Station located at Birch & Front. Horizontal Directional Drilling (HDD) is a trenchless technology that is being utilized for a portion of this project. HDD is utilized when conventional trench construction for pipe cannot be accommodated, installing the pipe under the bay is a prime example when HDD is beneficial.

In the past, the flows from Eastside are conveyed through Bunkerhill and the downtown system. This new line will eliminate the flows from entering the downtown system, thus increasing capacity for future development in the downtown area.

Construction is currently underway and the portion of the force main that is located under the bay is being horizontally drilled. This process takes about one month to complete. First, they have a casing drilled into the ground that acts as a sleeve around the pipe, the area along Birch & Front is used to drill the sleeve. The Millicoma Marsh Trail is being utilized as a staging area for the fused pipe, once the pipe is all fused and the drill makes it across the bay, they will pull back a fused pipe. The total distance for this HDD project is 2200 feet. This is a very exciting project for the City!