Maritime Link
Location: Newfoundland & Labrador
Client: Emera Newfoundland & Labrador
Timeframe: 2017
Key Personnel: Todd Menzies, Greg MacNeill, Vince Goreham
Project Description
The Maritime Link Project involved the construction of hundreds of kilometers of power transmission infrastructure in order to allow Nova Scotia to import renewable energy from Muskrat Falls in Labrador. This project took shape after engaging with Mi’kmaq stakeholder, various environmental studies, and multiple surveys .
Harbourside’s Role
Harbourside, worked on several phases of the Maritime Link Project. This involvement began with planning and extended to completion of construction.
Harbourside’s Scope of Work:
• Geotechnical support during concept design.
• Geotechnical Investigations.
New substations in Bottom Brook, NL; Granite Canal, NL; and Woodbine, NS
Converter stations in Bottom Brook and Woodbine
Transition compounds in Cape Ray, NL, and Point Aconi, NS
Grounding Sites (Marine and Land-based) Indian Head, NL and Big Lorraine Harbour, NS
HDD Investigations (Marine and Land-based) in Cape Ray, NL and Point Aconi, NS
• HVDC Transmission Line Construction
• Geotechnical support during detailed design
Harbourside, acting at the request of Emera Newfoundland & Labrador (ENL) provided additional technical resources to support the design and construction of anchors and micropiles for 452 HVdc guyed steel-lattice transmission towers. This work took place from March to December 2017.
The scope of work for the project included:
Site Presence. Inspected and reviewed installation and testing of anchors, audited select test results, helped solve issues encountered in the field, and ultimately acted to reduce ENL’s risk on the project.
Engineering Design. Reviewed existing and new geotechnical information to determine unique ground conditions and provided engineering recommendations where existing designs did not reflect specific subsurface conditions encountered in the field.
Support with Data Management. Junior engineering staff were engaged to support data management; specifically, with respect to the contractor’s rapid submission of drill, grout, and test records for over 1200 anchors.
Inspection and Testing. Through work on this project, the Harbourside team developed a novel approach to inspect grouted anchor installations using a low strain dynamic, non-destructive testing technique with the Pile Driving Analyzer (PDA). A program was conducted which included testing of 1262 anchors for the HVDC transmission Line in Newfoundland.
Project Closeout and Documentation. Continued to support ENL with quality review and contract administration developments in the weeks following completion of construction.
Harbourside’s role was primarily in support of anchoring guyed towers along the alignment. However, during construction our services extended remediation of select sites and asset protection.
HVdc Slope Stabilization – Cape Ray
At Cape Ray, Newfoundland, several towers were constructed along a steep talus slope adjacent to the Trans Canada Highway. Harbourside carried out the design of slope stabilization measures and rockfall protection berms for numerous structures through this area.
The talus slopes were stabilized through the use of rockfills and a system of tiered boulder walls. This enabled access to construction equipment and remediated disturbed slopes through the rugged terrain.
HVac line Slope Stabilization Design
Following the completion of the HVac line, Harbourside was engaged to design remediation and stabilization of active slopes for a series of structures near the Bottom Brook end of the alignment.
The remediation design combined the regrading of the active slopes with the use of TECCO mesh and soil nail system. The mesh and nail system was used to improve the factor of safety of the over-steepened soil slopes where stable slopes could not be constructed due to right of way constraints.
Unique Challenges
Much of the work for the Maritime Link had to be done in relatively remote locations. In these circumstances, the transportation of equipment and personnel becomes a challenge. Helicopters were required at certain work sites. Further constraining operations were the onsite weather conditions, and a narrow seasonal window when work could be completed safely.
Social Impact
The Maritime Link is an important piece of infrastructure in Atlantic Canada’s move towards more sustainable sources of energy. As the effects of climate change become increasingly evident, the shift away from fossil fuels becomes essential. The connection provided by the Maritime Link is one more step towards a greener future. It is an essential component for provinces like Nova Scotia, who intend to be carbon net zero by 2035.
