Great Lakes Water Authority 96-inch Water Transmission Main Relocation Project–Phase 1

Water Transmission


2,200 linear feet (LF) of 96-inch Welded Steel Pipe per AWWA C200 with Polyurethane Coating and Cement Mortar Lining




Great Lakes Water Authority, Southeast Michigan


Jacobs Consultants, Inc.

To improve future operations and maintenance of their water transmission system, the Great Lakes Water Authority (GLWA) will be decommissioning approximately 2.3 miles of an existing water transmission main and installing a 2.5-mile-long 96-inch diameter water transmission main along a new route. Northwest Pipe Company supplied 2,200 LF of engineered steel pipe with cement mortar coating and polyurethane lining to support Phase I of this multi-phased project. The new steel pipeline will connect to the existing 96-inch water transmission main, a PCCP that has been in service since 1967. The existing 96-inch water transmission main extends approximately 32 miles and conveys treated water from the Lake Huron Water Treatment Plant to communities in Lapeer, Macomb, and Oakland Counties in southeast Michigan.

Construction of the Phase 1 project is part of a broader regional infrastructure package coordinated between the GLWA and the Road Commission for Oakland County that includes roadway improvements along the Avon Road corridor between Rochester Hills and Shelby Township in Metro Detroit.

The new 96-inch water transmission main relocates the water transmission system around the property limits of a closed landfill and other privately owned commercial and residential properties, making the system more accessible to operators. In addition, new isolation valves included along the large-diameter water main will allow GLWA to ensure uninterrupted water service while performing future maintenance and repairs.

Northwest Pipe Company is also supplying spiralweld steel pipe for Phase II of the project, which involves installation of an additional 7,985 LF of pipe to complete the rerouted 96-inch water transmission main. Once complete, the new 96-inch water transmission main will help provide reliable water services for the over 1 million people it serves.