North American updateThe proposed replacement of the Alaskan Way viaduct in downtown Seattle with a 3.2 km-long bored double-deck road tunnel is symptomatic of the current trend in North America to take potential problems underground. The reality is that tunnels are more environmentally friendly and less visible than viaducts, and that their construction is less intrusive, making them more likely to be approved and built, especially with USD500 billion of economic stimulus funding being made available for new spending. If Seattle has its way, tunnel construction will begin in 2011 funded by a fuel tax and federal grants. The project qualifies for TARP 2 funding, so will probably be fast tracked for an earlier start. More at www.wsdot.wa.gov/Projects/Viaduct/. Meanwhile, if Governor Schwarzenegger can be believed, California will circumvent its current financial woes to authorize the proposed USD40 billion (US$1 = EUR0.72), 1,290 km-long (1 km = 1.6 miles) high speed rail system to serve San Francisco, Los Angeles and San Diego, with branches to Sacramento in the north and Irvine in the south. Dependent upon chosen alignment, the route includes between 21 km and 37 km of tunnels of maximum lengths between 5.5 km and 8 km. Invitations to tender for construction are planned for 2011, with project completion 2020. For the latest programme management presentation visit www.cahighspeedrail.ca.gov. Also in California, of the 19 alternatives studied for the proposed Westside Extension, two subway recommendations have emerged. A decision on whether the alignment of the 19-20 km-long, USD5-7 billion extension should be along Wilshire or Santa Monica Boulevards will be taken shortly, signalling an EIS and opening the way to fast track design. More from www.metro.net/projects_studies/westside/default.htm. During 2009, another EIS will be undertaken in San Francisco for the 25.6 km-long extension of BART to Milpitas, San Jose and Santa Clara, which includes 6.4 km of twin running tunnels and three underground stations. Visit www.vta.org/bart. Completing the west coast line-up is the San Diego water supply tunnel, where Traylor/Shea is battling against the odds through hard conglomerate on this essential 6.4 km link between the San Vicente reservoir and the metropolitan area. A 2.62 m ID pipeline is being installed in the tunnel, which is being advanced using every excavation and support method known to mankind. More from www.sdcwa.org and tunnelbuilder archive us/47.In Atlanta, Georgia contractor Peter Kiewit has been awarded the 2.86 km-long, 4.45 m ID South River wastewater tunnel that will eliminate sanitary overflows, and is presently mobilizing.In New York, the Camp Dresser & McKee and Hatch Mott MacDonald joint venture is providing engineering services for replacement of two existing potable water siphons crossing New York harbour between Staten Island and Brooklyn by 1.9 m-diameter pipeline within a 3.8 m-diameter, 3.2 km-long tunnel to be bored by EPB or slurry TBM.In Miami, Florida there is a flurry of activity to refinance the port tunnel, a project that has been mooted since March, 2000, see tunnelbuilder archive us/43. Visit www.portofmiamitunnel.com.Up in Vancouver, the Port Mann project requires a 3 m-diameter, 1.05 km-long water tunnel to be driven under Fraser River between Coquitlam and Surrey at a depth of 40 m below surface. Final design is underway and bidding should take place mid-2009. For more, visit www.metrovancouver.org. Also in Vancouver, the twin 7.1 km-long, 3.8 m-diameter Capilano-Seymour water supply tunnels are being restarted, and Metro Vancouver has asked three prequalified joint ventures to resubmit proposals. For more history and background visit tunnelbuilder archive ca/25 and www.metrovancouver.org/services/constructionprojects/water/pages/seymourcapilano.aspx.The tunnelbuilder archive contains full details of all major US and Canadian projects undertaken over the last ten years. 08/09.