The Highway 104 Twinning Project represents a key upgrade along a vital transportation corridor in Nova Scotia. Spanning 38 kilometers between Sutherlands River and Antigonish, this major infrastructure initiative is designed to improve safety, traffic flow and long-term transportation efficiency in Eastern Canada.
EXP served as both the owner’s engineer and geotechnical consultant for the Highway 104 Twinning Project. Delivered through a Public-Private Partnership (P3) model, the project spanned over five years of planning, investigation and construction. The project included the construction of new highway segments, extensive upgrades to existing infrastructure and environmental enhancements.
Geotechnical investigation
Our involvement began with a comprehensive geotechnical investigation, focused on 38 kilometers of proposed highway alignment. Our team conducted assessments for 15 bridges or structures and 5 culverts. The investigation was executed in two phases and involved roughly 1,200 boreholes strategically placed along the alignment, including proposed bridge, overpass and culvert sites.
As the project geotechnical consultant, our team managed and coordinated the subsurface investigation, providing critical data to inform design decisions and help mitigate construction risks. Engineering site visits were conducted throughout the investigation to monitor progress and deliver timely updates to stakeholders.
Construction oversight and engineering services
EXP’s team was selected for the role as the owner’s engineer during the construction phase of the project. The project scope included the construction of 10 kilometers of new four-lane divided highway and the twinning of 28 kilometers of existing two-lane highway. In addition to upgrading and paving the existing section, the work featured two new interchanges and 24 new bridges. Environmental enhancements were also a key component of the project, with the integration of wildlife corridors and fencing designed to protect local ecosystems and reduce animal-vehicle collisions.
Throughout construction, our team provided oversight and quality assurance services. We conducted site audits and fabrication audits to assess compliance with design specifications and safety standards. Granular material analysis was performed on samples of Type 1 Gravel, Type 2 Gravel and fill against structure to verify materials met engineering requirements.
Client collaboration and integrated services
EXP worked closely with the Nova Scotia Department of Public Works throughout the project, delivering a full suite of services, including geotechnical investigations, construction oversight, materials testing, roadway engineering and audits. Our integrated approach helped ensure that the Highway 104 Twinning Project met its performance, safety, and environmental objectives. The successful completion of this project, marks a significant improvement in Nova Scotia’s transportation network and reflects our commitment to engineering excellence and collaborative delivery.
EXP’s involvement throughout both phases facilitated technical foundation and continuity from initial investigation through to final construction, contributing to the successful delivery of one of Nova Scotia’s most significant highway infrastructure projects.
Images courtesy of: Dexter Nova Alliance
Services
Owner’s Engineer, Geotechnical, Materials Testing, Quality Assurance