Managing Agency: South Essex Sewerage District, Salem, Massachusetts
Primary Contractor: Caldwell Marine International
Primary Consultant: WSP/Parsons Brinckerhoff
Nominated By: New England Chapter
On March 3, 2013, the South Essex Sewerage District was forced to act immediately with the threat of an environmental crisis looming. The broken pipeline drastically changed the course of the South Essex Sewerage District, immediately placing all hands on deck to fix the pipe and evaluate the rest of the line. But the District soon learned that despite fully understanding that the magnitude of the circumstances was profound, correcting the problem would not come easily. Replacing the 6,000-foot-long twin pipeline would have been difficult enough to install across an active harbor never mind the rest of the hurdles that had to be overcome before the District, state and federal regulators, and local officials could finally breathe a sigh of relief.
After completing the permitting process, contractor Caldwell Marine was awarded the contract for the installation of the new pipeline. Just as they began to mobilize into Salem, the winter of 2014-15 produced a record amount of snowfall in the Boston area at over 110 inches. Most of that snow fell during the last weeks of January and throughout February. Caldwell proceeded to assemble their barges and equipment through the difficult winter weather conditions. Slow and steady progress began to ramp up until finally the weather broke in spring of 2015 when Caldwell was then able to set up a staging/pipe assembly area.
Caldwell faced difficult staging issues and submitted many different plans to accommodate 12,000 feet of 24″ HDPE pipe. This pipe was developed in SO-foot lengths and had to be butt-fused in a fashion to allow it to be floated out to barges. Trucking materials this large through a tourist city such as Salem was a concern, so shipments were staggered over a period of two months, which allowed the contractor to take delivery at a regulated pace and without overwhelming the City’s streets or the staging area. Fortunately, Caldwell Marine was able to work out a deal with Footprint Power, a direct abutter to the SESD Treatment Facility, which turned out to be a pivotal opportunity for the contractor to maintain a useful staging and assembly area on Footprint property with direct access from District property. Between the Footprint Power staging area and District-owned land, Caldwell was able to pre-assemble 500-foot lengths on land where they were pressure tested and eventually floated out to barges where they were fused into longer strands.
Despite the difficult conditions, the contractor managed to reach substantial completion by the contract completion deadline. It was a great feat completed by a strong team effort. From condition assessment to closeout, all members of the team had to perform diligently to ensure the well-being of the residents and environment.