Ellwood Water Treatment Plant


ellewood three pipes stacked

Pipe Specifications:

580’ of 75.4” OD x 1.25” Permalok®

250’ of 60” OD x 1.00” T-5 Permalok®




Pennsylvania American Water Company

Engineer Firm:

Buchart Horn, Inc., and Gannett Fleming


Bradshaw Construction

The new Ellwood Water Treatment Plant in Lawrence County, Pennsylvania, replaces a 100-year-old facility and increases capacity and reliability to local residents and businesses. The new structure will expand treatment of water from the Beaver River at a rate of 16 million gallons per day (mgd), which is a substantial upgrade from the previous capacity of 5mgd.

Our scope in the project includes supplying two 75-inch wide and one 60-inch wide tunnels both of which are installed via microtunneling. The 75-inch pipe will accommodate fresh water and the 60-inch pipe will provide carrier space for utility lines.

Our ability to manufacture Permalok in custom sizes is a great advantage in this project. The microtunneling machinery selected to install the pipe requires an unusual diameter of pipe. Despite the tunnel having a 75” OD requirement, the metric-based machine requires a 75.4” Outside Diameter pipe. We collaborated with the contractor to produce custom pipe with the least amount of waste. The pipe also includes a heavy wall to assist in the additional counteraction of buoyant forces while far exceeding the minimum standard for Rail Crossing.

With the installation team having a limited timeframe for mining, the structure of Permalok pipe supporting continuous tunneling, as opposed to being required to ‘stop and weld.’ In addition to increased production throughput, the contractor was able to proceed with tunneling operations prior to the completion of the cofferdam to keep ahead of schedule.

Northwest Pipe Company is proud to be part of the team and our role in this project, which was featured as one of Trenchless Technology Magazine’s 2019 Projects of the Year in the New Installation Category.