Affilated Engineers Inc. (AEI) and CDM developed alternatives for rehabilitation or replacing an existing steam distribution tunnel (circa 1939) at the University of North Carolina at Chapel Hill. The 2,400-foot-long tunnel crosses two city streets and is located within a narrow university-owned right-of-way mostly bordered by private residences. In addition to the tunnel, the right-of-way contains overhead electric and telephone lines, electrical ducts, storm drains, gas mains, and a parallel 1987 steam distribution tunnel.
During the preliminary alternatives evaluation, the team developed the concept of constructing a larger replacement tunnel capable of housing all the steam distribution piping and constructing this tunnel in the location of the existing 1987 tunnel. This concept allows the existing 1939 steam tunnel to act as a temporary bypass during construction, with no additional piping required. The 1939 tunnel will then be abandoned in place post-construction, saving the university demolition and disposal costs for this tunnel. The replacement tunnel will consolidate steam service, reduce costs, and minimize disruption during construction.
CLIENT: University of North Carolina at Chapel Hill
LOCATION: Chapel Hill, North Carolina