Background
This project was created subsequent to the emergency repair of two trunk sewer line drop-manholes near the discharge manhole of the force main from Kaneohe Bay #3 WWPS. The investigations of these two manholes and adjacent Kaneohe Bay Drive trunk sewers revealed several locations of the trunk line with severe deterioration. Most of the deteriorated trunk sewers are located in easements through private residential properties that are difficult to access for maintenance of the sewers and have generated numerous odor complaints from the residents.
Project Description
The Department of Design and Construction, City and County of Honolulu proposed to construct the Kaneohe Bay Drive Trunk Sewer Reconstruction project, located along the southeastern end of Kaneohe Bay. This project involved the reconstruction and rehabilitation of portions of the Kaneohe Bay Drive Wastewater System that serves residential properties in the area.
The major work of this project involved the construction of approximately1,600 linear feet of new 18-inch diameter and 15-inch diameter sewer trunk lines located along Kaimalu Place and Kaneohe Bay Drive. The downstream end of the line is connected to the Kaneohe Bay #2 WWPS and the upstream end is the Kaneohe Bay #3 WWPS force main discharge point. The new trunk sewer line replaced an existing trunk sewer line located within easements through residential backyards. The new trunk sewer line corrected deficiencies of the existing trunk sewer lines; including structural and hydraulic defects, lack of accessibility to the sewers for maintenance purposes, and complaints from residents of odors from the sewers located in easements through private properties.
The proposed project also included the rehabilitation of severely corroded 21-inch reinforced concrete and 24-inch cast iron influent lines to the Kaneohe Bay #2 WWPS with cured-in-place pipe (CIPP) lining. Defective collection system sewer lines and manholes tributary to the Kaneohe Bay #2 WWPS were also reconstructed with new pipes and manholes or rehabilitated with CIPP lining.Additionally, 12 collection system sewer line segments, tributary to the Kaneohe Bay #3 WWPS, have been rehabilitated with CIPP lining to minimize salt-water infiltration into the system. The rehabilitated sewer line segments included 10″, 8″, and 6″ diameter pipes.