Port Mann Water Supply Tunnel Port Mann Water Supply Tunnel <div class="ExternalClassA65A0485D13D4A67AF61F74A0003BF08"><p>​Once complete, this new water main will more than double the capacity of the existing main and help ensure the continued reliable delivery of clean, safe drinking water to the municipalities south of the Fraser River. The 3.5-metre-diameter, one-kilometre-long tunnel crosses between Coquitlam’s Maquabeak Park on the north side of the river, and Surrey on the south side. The tunnel is designed to withstand river scour as well as a major seismic event.</p><p>In late 2014, with approximately 80 percent of the tunnel excavation completed, the contractor experienced a blockage in the screw conveyor of the large Tunnel Boring Machine (TBM). The screw conveyor removes sand, clay, and rock as the TBM’s rotating metal discs cut through the ground to bore the tunnel. Repairs to the TBM were completed utilizing a method known as ‘ground freezing’, and tunneling has now resumed.</p> </div>http://www.metrovancouver.org/metroupdate/PublishingImages/issue09-port-mann.jpg2015-05-26T07:00:00ZGP0|#43c3f653-7096-4b77-bc83-97cb5d7ab958;L0|#043c3f653-7096-4b77-bc83-97cb5d7ab958|Issue 9;GTSet|#d14ffe11-45dc-48fb-8684-ff109cf15a74<div class="ExternalClassE946D5035AF94388BD5A4DDD535761E1"><p> Excavation of the new <a href="/services/water/engagement/construction-projects/port-mann-water-supply-tunnel" target="_blank">Port Mann Water Supply Tunnel</a> is scheduled to be completed this summer. A welded steel water main liner will then be installed in the tunnel and shafts to connect to the existing water transmission system with two new valve chambers that will be located at the top of each shaft. Construction of the $240-million project is scheduled to be completed in 2016.<br></p></div>