Opened in 2020, this new 265,000 gsf, 7-story courthouse was designed to use 40% of the energy of a typical facility and achieved LEED Platinum certification. Located in the historic Hamilton Canal District of downtown Lowell, the site formerly was utilized for a variety of commercial and industrial purposes, including as a railroad roundhouse and filling station.
As a result of its past use, the site soil and groundwater were contaminated with petroleum and metals. McPhail, as the Licensed Site Professional (LSP), characterized site soil for off-site removal and oversaw regulatory compliance with the Massachusetts Contingency Plan. Geotechnical design considerations for the building, which contains a partial basement level, included the presence of shallow bedrock and a high groundwater level as a result of the adjacent Hamilton Canal.
To achieve the required subgrade, an up to 23-foot deep excavation was completed which required a temporary soil nail wall and blasting to remove bedrock. The desire to eliminate the need to maintain pumps to lower groundwater over the life of the building led to the use of a waterproofed structural mat foundation that was supplemented with rock anchors at the attached low-rise parking structure. During the early design stages McPhail was also responsible for the installation and thermal conductivity testing of a geothermal test well, though geothermal was ultimately not included in the completed project.