By rosebell
A working model of the TBM that is due to excavate beneath the Straits of Mackinac is the content of Enbridge’s Great Lakes Tunnel Information Centre expansion.
Including cutterheads that slowly rotate, giving visitors an idea of how the tunnel will be excavated, the 6.7m-long TBM model is situated in a long, darkened room that simulates a tunnel, whereas the actual TBM that is going to build the tunnel for Enbridge’s Line 5 pipeline, will be about 183m long with an internal diameter of 6.4m.
With the aim of leaving room for regular inspections, the pipe itself will be installed on rollers bolted to the side of the tunnel and the tunnel could also house fibre-optic cables or other equipment to boost internet connection and emergency communications.
Considering that the tunnel is slated to lie at least 30.5m below the lakebed of the Straits, it will eliminate the chance of an anchor strike to Line 5 and decrease the risk of a spill into the Straits.
Responsibility of leading this tunnel construction was awarded to Mackinac Straits Partners, a joint venture of Barnard Construction Company and Civil and Building North America in May last year.
According to Jordan Hoover, Mackinac Straits Partners project manager: “For more than a year, we have been doing pre-construction work for the Great Lakes Tunnel. Once final permits are received and we have the green light to construct, we’ll be ready to go.”
The scheduled date for releasing the draft Environmental Impact Statement by US Army Corps of Engineers (USACE) is May 30, while that will commence a 30-day public comment period, with a final USACE decision anticipated in the autumn.
Fast-tracking the environmental review process, the USACE granted national energy emergency status for Enbridge’s proposed tunnel for its Line 5 oil pipeline in April.
With the final permits on the horizon, Enbridge has commissioned a competition to name the TBM. The name should honour a local female from any period in history who lived in or made contributions to the Straits. Entries should be submitted to Line5Info@Enbridge.com by June 7.
