A mechanical mole is now drilling a new tunnel under the Fraser River to deliver drinking water to Surrey and other neighbourhoods on the south side of the river.
The tunnel boring machine was lowered in December by crane down a vertical access shaft on the Surrey shore and on Feb. 14 the tunneling phase of the $240-million construction project got underway.
It’s the largest of a series of regional water infrastructure projects underway or planned.
The one-kilometre, 3.5-metre-wide Port Mann Water Supply Tunnel will run under the river bed just downstream of the Port Mann Bridge, between two 60-metre-deep shafts dug in 2011-12 in Coquitlam and Surrey.
It will more than double the carrying capacity of an older, smaller water main under the river that brings drinking water from the Coquitlam reservoir.
The new water main, with a welded-steel pipe throughout the tunnel, is also designed to withstand an earthquake as well as the scouring power of the river, which damaged the old water main in 1997 and forced temporary water restrictions in Surrey and area.
“This investment will ensure the continued and reliable delivery of high-quality drinking water to communities like Surrey, Langley and Delta,” Metro board chair Greg Moore said. “Few people will see this massive construction project first hand, but hundreds of thousands of residents will benefit.”
Tunneling is slated to finish this summer and the full project is to wrap up in mid-2015.
The cost is paid by residents through Metro utility fees, which total $423 this year for water, sewer and waste services for an average $725,000 home.
A tunnel boring machine was lowered down a 60-metre shaft in Surrey in December. It began drilling a new water supply tunnel under the Fraser River in February. Photo, videos courtesy of Metro Vancouver.