Replacing an Aging Infrastructure:Systematic Replacement of 7 Miles of Major Water Transmission Main

This paper will discuss the systematic replacement of over 7 miles of water transmission main (36" to 48") along US Route 29, a very highly traveled corridor in Howard County, MD. The water main replacements are part of a holistic approach to upgrade aging pipelines in the municipality's distribution system, as well as to provide water to areas of projected growth within the system and to alleviate water pressure problems that have been experienced within the system. Initial work started with internal visual investigations, acoustic assessment of the existing PCCP mains and forensic testing of selected sections, followed by detailed evaluations for replacement of the failing mains along this selected 7-mile corridor. The County's distribution system includes many pipelines that have either reached or surpassed their useful life or that are too small to meet future demand projections.