Kamehame Tunnel Waterline (O’ahu)
The Kamehame Tunnel Waterline was a Design-Build Emergency Repair project with Sam O. Hirota Inc, for the Board of Water Supply/ City and County of Honolulu. It consisted of the design and installation of 2,200 feet of 30-inch HDPE pipe within an existing 36-inch CCP water main plus installation of two 30-inch BGGVs in Type “A” Manholes.
Staging areas were provided by the BWS on each end of the utility tunnel, to store the 30-inch pipe material and fittings as well as ultimately to conduct the pipe feeding, butt-fusing and pipe pulling operations to slip-line the 30-inch HDPE pipe into the 36-inch CCP water main.
The Kalama Valley Big Giant Gate Valve was a challenge due to its location in the middle of Mokuhano Street, a 25 foot wide, two lane road with a bus route. This site also required the re-location of approximately 60 l.f. of an existing 12-inch waterline in order to fit the new Type “A” Manhole.
Excellence in project management and state-of-the-art advancements were key elements that made this project successful. Pulling of the 30-inch butt-fused HDPE pipe and making the final connection in a hard to reach, space-challenged location required an innovative approach in construction techniques.
