Throughout 2025 Caldwell Marine International will be installing a power cable to bring clean electricity generated from Canadian hydropower to the bustling metropolis of New York. A 10km section of the project was through the Harlem and Hudson River in depths ranging from 5 to 20m. This span consisted of two HVDC cables and a fibre optic cable bundled together with Uraduct. North Sea Systems were contracted to provide CableFish and a team of operators for the touchdown monitoring along this section of the project.
For this project the system was equipped with a Sonardyne SprintNav Mini INS with an integrated DVL and a Tritech Gemini sonar. The DVL enabled INS was able to provide an accurate position reading during times when the shallow water rendered the USBL unreliable.
The touchdown point was monitored continuously using both sonar and video and being a busy urban waterway there were plenty of hazards and crossings to negotiate. Having the Gemini sonar scanning the river bed approaching the cable meant that these hazards could be anticipated in good time allowing the crew to take remedial action.
One of the major benefits of CableFish is that the route ahead can be observed while simultaneously monitoring the touchdown point.
Greg Gashlin, Submarine Cable Manager, Caldwell Marine International.
“CableFish provided us with a continuous and accurate position of the cable touchdown point. The dual sonar system gave us an unparalleled awareness of the subsea situation, enabling us to avoid obstacles and negotiate crossings with certainty.”
