C-Line Sanitary Sewer Replacement
Trihydro undertook a project for the City of Laramie to improve the sanitary sewer system reliability and reduce system maintenance.
The City of Laramie contracted Trihydro to replace segments of the C-Line Interceptor along 1st and 2nd Streets from Hancock to Canby Street and along Canby Street and Baker Street from 1st to 6th Streets (Phase I). This project was completed to improve sanitary sewer system reliability and reduce system maintenance.
Phase I included new installation, removal, and replacement of existing reinforced concrete pipe (RCP), VCP, and PVC sanitary sewer pipe with approximately 2,800 linear feet of new 36-inch A-2000 PVC, 1,050 linear feet of new 15-inch PVC, and 390 linear feet of new 18-inch PVC sanitary sewer pipe. Hydraulic modeling confirmed sanitary sewer line sizing. This project also relocated approximately 750 linear feet of 8-inch diameter PVC potable water main. Critical Phase I project issues included utility conflicts, installing a large diameter pipeline, crossing a WYDOT roadway, construction sequencing, and traffic control.
Shortly after Phase I completion, the City of Laramie extended Trihydro’s contract to replace the C-Line Interceptor along 6th Street between Canby Street and Ivinson Avenue (Phase II). Trihydro completed cleaning and video inspection work along the sanitary sewer line to verify pipe sizes and materials, identify structural deficiencies, and locate services. Field surveying and potholing activities were also conducted to evaluate manhole rim elevations, sanitary and storm sewer invert elevations, potable water line depths, and crossing utility locations and sizes. Hydraulic modeling was then used to evaluate the existing sanitary sewer capacity and determine the appropriate new sewer line size.
The project included installing 3,200 linear feet of 24-inch PVC sanitary sewer line to replace the existing 15-inch and 18-inch VCP, along with new sanitary sewer services. Select portions of the storm sewer system were modified with new manholes, inlets, and laterals to avoid conflicts, and several hundred feet of 6-inch and 8-inch iron potable water line were replaced with PVC. Additional work involved replacing select curbs, gutters, and approaches. Trihydro also coordinated with the City of Laramie to prepare and distribute public notification flyers to nearby residences and businesses.
