By starting work in late November on a $200-million upgrade of its central transmission system, Vancouver is making its first significant investment in the city’s power grid in 30 years. The project includes construction of an oversized three-story substation to meet future capacity needs and a tunnel beneath one of the city’s major waterways.
Marcel Reghelini, BC Hydro senior project manager, says the work is happening in Mount Pleasant, a fast-growing neighborhood no longer adequately served by three aging substations. “We’re putting in a new substation closer to the load center and transferring existing customers over to the new substation before the existing 50-plus-year [old] distribution facilities experience an end-of-life failure,” he says.
The owner’s geotechnical consultant, Golder Associates, recommended using a horizontal drilling machine instead of a tunnel-boring machine to cut a new access tunnel through the glacial till and hard granite boulders at the bottom of Vancouver’s False Creek. The choice helped cut the original $16-million budget to $10 million.
“You would have a much larger tunnel using the TBM,” says Reghelini, “and it would take much longer to complete than the horizontal drilling machine.”
In addition to developing conceptual designs for the bore path and technical requirements for the cable facility, Golder’s Vancouver office is evaluating and managing contractors during the drilling, says Reghelini. “We have put [a request for proposals] out on the street for a drilling contractor, and we’re in the process of reviewing the proposals that we got,” he says.
Furthermore, BC Hydro worked “to reduce the risk [and] have a smaller impact on the environment and on the public during construction,” Reghelini says.
The Vancouver upgrade is part of a broader plan by BC Hydro to reinvest in British Columbia’s overall transmission and distribution systems. More substations and transmission lines are on the way.
The upgrade, in turn, will require continued consultation with a public concerned as much about the impact of transmission lines on their neighborhoods as they are about getting cheap electric power. BC Hydro wants support for “a facility that fits in with the neighborhood,” says Reghelini.