The San Jose Mercury News carries the full Associated Press story on the recent opening of the 21-mile Loetschberg Base Tunnel. Billed as the world’s longest land tunnel, it is a trainway built through the Alps to ease road congestion and deliver skiers twice as quickly from south of Bern to the gateway town of Visp near the Zermatt and Gourmayeur ski regions of Switzerland and Italy, respectively. The tunnel’s cost in U.S. dollars: $3.5 billion. Passenger trains will reach speeds of 150 miles per hour in the tunnel; freight trains 100 mph. BBC reports the tunnel will eventually handle up to 42 passenger trains and 80 frieght trains per day. A picture of the tunnel’s construction is below, right. AP notes:
Switzerland is at the center of a north-south European axis where traffic has increased more than tenfold since 1980. The Swiss have tired of traffic jams caused by big rigs and vacationers filling their narrow valleys, and the rail plan has remained popular despite running billions of dollars over budget. “We did not want to become part of the road corridor for 40-ton trucks streaming north and south, and so decided to opt for rail tunnels,” (Swiss Transport Minister Moritz) Leuenberger said.
A planned twin train tunnel was not built due to cost constraints, but had it been, even at an additional cost of twice the one built, the total cost per mile would have been $500 million. (For now, trains going in different directions will take turns using the tunnel).
Globally, train and roadway tunnels are being built in a variety of locales, at costs per mile far less than the $3.4 billion estimated for the (mile-long) downtown Seattle waterfront tunnel to replace the crumbling and earthquake-prone Alaskan Way Viaduct section of the regional aterial, State Route 99. That proposal was firmly rejected by local voters in an advisory March ballot measure, but as the Seattle Post-Intelligencer reported last month, an inland tunnel replacement for the viaduct’s stretch of SR 99 – as opposed to a waterfront tunnel like that rejected by voters – is being discussed.
Some downtown businesses are talking about another tunnel replacement, dug several blocks east of the waterfront with boring machines rather than formed in an open trench, to avoid shutting waterfront businesses. “We shouldn’t discard any ideas at this point,” said John Blackman, chairman of Argosy Cruises and head of a waterfront historical group.
The idea of an inland tunnel replacement for the viaduct, combined with surface-transit improvements and perhaps even tunnel tolling as part of a larger regional tolling strategy, is likely to get further consideration in coming months. Limiting taxpayer exposure on tunnel costs via state-of-the-art “deep boring” tunnel technology and by private investment will likely be part of that coming conversation.
Economist Glenn R. Pascall, a regular guest op-ed columnist for the Puget Sound Business Journal outlined the case for an inland tunnel to replace the Viaduct in a piece he wrote for that publication shortly after the advisory vote. (As he acknowledges in the op-ed, Pascall also is advising our Cascadia Center For Regional Development on viaduct replacement strategies).
The question is whether there is a way to liberate the part of the city that has been violated by the viaduct, while maintaining essential transport capacity, holding construction disruption to an absolute minimum, and financing the project’s dollar cost in the very low billions. There may be an answer: the Bored Tunnel Alternative. Truth in packaging: I’ve been working as an adviser to a group that has been examining alternatives over the past few months and has focused on this one as the most promising. Members of the dialogue include Bruce Agnew, director of the Cascadia Center; John Wilson, a principal at the Gallatin Group; and Gary Lawrence, a principal at Arup consultants….they are poised to put forth the case for such an approach soon.
Bored tunnels have been built around the world for decades, but the technology of boring machines (called “moles”) has advanced by leaps and bounds in recent years. This has enabled larger diameters (up to 51 feet), increased productivity and greater control of ground movements in a wide variety of conditions. Recent bored roadway tunnels include the M30 tunnel in Madrid, the SMART tunnel in Malaysia, the 4th Elbe Crossing in Germany, and the A86 West Tunnel in Paris. This type of technology is being used in Seattle by Sound Transit on its Beacon Hill tunnel, and is proposed for the University Link Extension and for King County’s Brightwater project.
Cascadia Center expects to soon announce the date for a fall roundtable discussion on an inland bored-tunnel replacement for the crumbling, unsafe and obtrusive, crime-friendly waterfront elevated viaduct now marring Seattle’s downtown.
It is too early to say right now what would be a realistic cost estimate, though that – and firm taxpayer protections – must and will be part of any proposal brought forward.
But it is certainly not too early to say that if the Swiss can build a 21-mile train tunnel through the Alps for $3.5 million – and even granting that a more extensive dual tunnel might have cost as much as three times that figure – we ought not to presume that a stacked, bi-directional, four- to six-lane SR 99 lidded bypass running for a length of one mile or slightly less under downtown Seattle will be a budget-buster. Especially if private-sector partners help foot the bill.
The local debate will again become pitched, with the environmental lobby asserting we can make do quite well with no new viaduct or tunnel replacement for the old structure. It’s true that surface and transit improvements will be an important piece of the viaduct replacement puzzle. But when the roadway is torn down, as it certainly will be, replacment capacity at or near the viaduct’s 110,000 vehicles served daily must be created. Otherwise, the region’s remaining major north-south artery, I-5 – already badly congested – will suffer crippling delays inimical to Puget Sound’s economic competitiveness.