20-INCH TRANSMISSION MAIN - CLEANING AND LINING
CLAREMONT, NEW HAMPSHIRE

In 2006, as part of a larger water main project, Dufresne Group (DG) provided the design and construction oversight for the cleaning and lining of approximately 4,500 linear feet of an existing 20-inch cast iron water main.

The 20-inch main is a major transmission main used to transmit water from the Water Treatment Facility into the central zone. Prior to the project, the C-value for this water main was estimated at 60. After cleaning and lining activities were completed, the estimated C-value of the 20-inch water main is 120-130.

Key Project Features:

• The project required coordination with the installation of a new 16-inch water main that was used for temporary water while the 20-inch was being cleaned and lined.
• Traffic Control requirements in a heavily trafficked area, including NH Route 103 (Washington Avenue).
• One entrance pit located in an abandoned chlorination building.
• Coordination with Water Treatment Facility operations.

Heitkamp of Watertown, Connecticut provided the services for the cleaning and lining portion of this project.

Water main before and after cleaning and lining activities