Back to the Future: The Modernization of a Historic Mill Village Community

摘要

Spartanburg Water retained CDM Smith, Inc. (CDM Smith), Greenville SC, to design and manage the construction of a collection system rehabilitation project in the Beaumont Village of Spartanburg, SC. Beaumont Village, designated as a local historic district neighborhood in 2011, was built, owned, and maintained by a local cotton mill during the great southern textile boom of the early 1900’s. In the 1980’s the City of Spartanburg was prescribed ownership of the sewer system when the mill was decommissioned. It was in 2008 that the City of Spartanburg transferred ownership of the entire city collection system to the Spartanburg Sanitary Sewer District (aka Spartanburg Water). The two entities entered into an agreement at that time to jointly fund an upgrade of the existing collection system in the Beaumont Village. The collection system for Beaumont Village was constructed in the early 1900s as the homes in the Mill Village were built. The system traversed streets, railroads and backyards and consisted of vitrified clay pipes (some inadequately sized), limited manholes and access points, and pipes that had reached the end of their useful life. In order to minimize the impacts of the rehabilitation project to the streets, residential property and the residents’ lives of the Village, Spartanburg Water wanted to maximize the use of trenchless technologies, thus cured-in-place pipe (CIPP) lining and pipe bursting were the primary practices employed throughout the system rehabilitation. The project rehabilitated over 15,350 linear feet of 8-inch and 6-inch vitrified clay pipe utilizing primarily cured-in-place and pipe bursting construction methods with conventional open cut methods being used as sparingly as possible. Construction also involved installation of over 5450 linear feet of 4-inch service line piping and 47 manholes and meter box access points throughout the system. During the design phase prior to construction, the contractor was required to physically locate and create video records of all the sewer lines sighted for rehabilitation in a preliminary closed circuit TV analysis of the system. Preconstruction video logs and “potholing” the existing sewer system revealed numerous sections of broken pipe, unaccounted for service laterals, tree root damage, unrecorded pipe repairs, and home additions and outbuildings constructed over the sewer lines. Field investigations also revealed a water distribution system placed in the same trench as the sewer line when the community was built, which at times made it difficult to make repairs to the sewer system without impacting the water service to the residents. All of these challenges required CDM Smith, Spartanburg Water, and the contractor to frequently ”field engineer” these situations when encountered so that the proposed construction schedule could be met. The project was bid in January 2011 using a bid form that included CIPP, pipe bursting and open-cut replacement unit prices to allow Spartanburg Water to switch between rehabilitation methods as site conditions warranted. The project was awarded to Portland Utilities Construction Company, Inc., of Portland TN with project completion expected in September, 2011. This paper will present a case study examining the issues that led to the selection of the appropriate rehabilitation technologies, design, permitting and construction challenges.