Tunnel boring project for Vancouver water system reaches breakthrough
joc staff writer
A consortium of contractors has completed the tunnel boring phase of construction at the Seymour Capilano water filtration project in North Vancouver, B.C., after delays and cost overruns when Metro Vancouver fired the original contractor.
“It is quite significant in as much as this is the completion of all the drilling of all the tunnels, which has been underway for quite some time now,” said Tim Stevenson, chair of Metro Vancouver’s Water Committee.
“It’s a big milestone. This is the most significant and the most expensive phase of the project.”
A partnership made up of Frontier-Kemper, J.F.Shea and Aecon used a raised bore to complete excavation on the second of two vertical shafts that are 270 metre deep and four metres in diameter. The raised bore work reached the surface on April 15 next to a new pumping station near the Capilano reservoir.
“The biggest challenge was when the previous firm, Bilfinger-Berger, said they couldn’t continue and told us it was the result of rocks falling inside the tunnel,” said Stevenson. “That caused us a two-year delay, because we had to find another firm to continue on.”
Metro Vancouver hired Bilfinger-Berger Canada in 2004 to construct the twin tunnels, which start near the new water filtration plant in the Lower Seymour Conservation reserve and end at the Capilano Reservoir.
The construction of the twin tunnels was initially estimated to cost about $100 million.