The City of Marion’s 8-inch waterline through downtown is approximately 80 years old. The line was installed in 6-foot joints and is experiencing corrosion of the mechanical joint bolts at almost every joint. The City has had to repair the waterline at numerous locations throughout Main Street. This line serves as the backbone for the water system and is also undersized. Due to the age of the line and the velocity during peak usage and flushing exercises, the pressure in some areas of the system drop below the minimum pressure required by the Division of Water.
The City of Marion contracted Eclipse Engineers to design a replacement for the old waterline. Currently, 8,000 feet of 12-inch ductile iron waterline is being installed. The new waterline must connect to the crossing lines at all intersections. Since very few of the system’s valves operate correctly, approximately 17 valve insertions are being designed in the project. This will allow the new waterline to connect to the existing system without taking any of the existing system out of service until all of the final connections are made. Approximately 75 service lines to homes and businesses are being connected to the new line.
Much of the line is underneath pavement and had to be bedded and backfilled accordingly. Close coordination with the Kentucky Department of Highways was required. Entrances to homes and businesses had to remain accessible at all times. Once completed, the new 12-inch ductile iron waterline will provide improved pressure and water quality for the residents of Marion. City workers will also have means of isolating parts of the system for repair and flushing that they didn’t have before.