The carbon cost of building and operating light rail

Rail mass transit is supposed to be good for the environment. But a leading critic of Sound Transit's Link light rail project offers metrics that suggest the environmental costs are much higher than those of more vanpools, more carpools, more buses, and, particularly, more bicycling.
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The light-rail tunnel through Beacon Hill. (Sound Transit)

Rail mass transit is supposed to be good for the environment. But a leading critic of Sound Transit's Link light rail project offers metrics that suggest the environmental costs are much higher than those of more vanpools, more carpools, more buses, and, particularly, more bicycling.

Excavating a six-mile, twin-bore tunnel and hauling away the rocks and muck is like digging a huge hole and pouring money in it. The lesson has been confirmed by the Beacon Hill tunnel, an experience so sobering that it prompted Sound Transit, which is building light rail from downtown to Seattle-Tacoma International Airport, to bail out of a First Hill station, to save $350 million and reduce risk exposure. Sound Transit pegs the cost to tunnel north from downtown Seattle at $500 million per mile. Worrying financial costs aside, what about the environmental costs and benefits of rail transit? Surprisingly, rail's environmental costs are quite adverse. Start with the tunneling, which turns out to entail a prodigious outpouring of energy and release of greenhouse gases. To extend light rail service north from downtown, the next phase, Sound Transit will have to dig through and remove more than 600,000 cubic yards of rock and muck – equivalent to a pile of debris 350 miles long, three feet wide, and three feet high. Sound Transit plans to expend lots of energy digging and excavating that stuff: 17.4 trillion British Thermal Units, according to its environmental-impact statement, equivalent to the energy in 140 million gallons of gasoline. That much gas, or diesel, would fill 8,000-gallon tanker trucks lined up from Seattle to Canada. If all the energy consumed by tunnel-excavating and hauling is generated by gasoline or diesel, it will emit nearly 1.3 million tons of greenhouse gases, CO2, into the environment. As an offset, Sound Transit claims it will save 14,000 tons of CO2 annually by running light rail trains on electricity, sparing the region emissions that otherwise would be generated by automotive traffic. Even if granted, it would take 90 years from completion of the line to break even on the energy transaction. If Sound Transit should manage to cut tunnel-related greenhouse emissions in half, by aggressive use of hydro electricity and human labor, an implausible proposition, it still would take 45 years to break even. Moreover, the agency's calculations assume no improvements in automotive fuel efficiency. Yet Congress in this session might enact a measure to raise average mileage from 25 to 35 miles per gallon by 2018. That one conservation measure, a 40 percent per mile improvement even before the tunnel will be complete, would extend Sound Transit's greenhouse gas pay-back period to the year 2088. Further, public transit's contribution to fuel efficiency is exaggerated. According to the U.S. Department of Energy's 2006 Data Book, per-passenger energy consumed by rail transit is only 19 percent more fuel efficient than today's automobiles (2,784 vs. 3,445 BTUs per passenger mile). If the improvements before Congress are enacted, shortly cars will be more energy-efficient. Bus transit already is 25 percent less fuel-efficient than cars (3,445 vs. 4,323 BTUs). And the data make the energy performance of rail transit appear better than it really is. The reason is urban rail in the U.S. primarily is used in New York City, where it's more fuel-efficient than elsewhere, due to the packed subways. Here, the local rail energy consumption average is inferior to New York's. The most cost-effective and energy-efficient transportation option, it turns out, would be making more productive use of existing capabilities. There is a lot of spare capacity on King County Metro Transit buses and those of other local agencies, even on a large share of the rush hour routes. One obvious way to use that spare capacity is to make more of the bus rides free or much lower-cost. But when Chuck Collins, former Metro Transit director and former chairman of the Northwest Power Planning Council, put forth his Ride Free Express plan to make markedly better use of existing transit capacity, and incrementally strengthen the most heavily-used routes to handle new levels of demand, Sound Transit and its political allies tromped on it. vanpools would be another easy way to increase utilization of our present systems. According to the Department of Energy, vanpools are three times more fuel-efficient than transit, 1,294 BTU's per passenger mile. They're far less costly to operate and much more flexible than rail transit. But they're discriminated against, as a commuting mode. Bus transit is heavily subsidized, rail transit is hugely subsidized, while vanpools are but slightly helped. Today, Sounder commuter rail costs $20 per boarding (one-way trip) to operate and, factoring in annualized capital costs, a total of $100 per boarding. (The average fare is less than $3.) Van-pooling, by contrast, is almost 100 percent paid for by those who use it. vanpools could swiftly surpass Sound Transit rail in ridership, at a tiny fraction of the cost, with superior energy efficiency. Again, Sound Transit and its allies stomped on this idea, also pushed by Collins, and the environmental community sat on the sidelines. There are numerous other environmental costs to rail. Sound Transit is paying nearly $393 million, almost five times the "very conservative" price tag it told voters, to gain access to Burlington Northern Santa Fe's rail corridor between Everett and Seattle for the Sounder trains. A substantial chunk of that money will be used by the railroad to encroach on Puget Sound tidelands – one of the largest industrial fills of tidelands since Washington adopted the Shoreline Management Act in 1971. For most of the distance, the line runs right along the shoreline, not many feet above high tide, which might be oblivious to the impact of global warming. Another environmental drawback is that Sound Transit actively promotes and subsidizes sprawl by operation of Sounder commuter rail. It provides spacious, handy free parking at all Sounder stations and intends to build a lot more so people can live hither and yon, drive their single-occupancy vehicles to the train, and take long, lavishly subsidized trips to downtown Seattle to work. The same perks are provided for Tacoma Link, as a commute avenue to downtown Tacoma. Sound Transit Executive Director Joni Earl illustrated the inducements to sprawl in the February/March 2007 edition of Mass Transit Magazine, which featured her on the cover: "Because I ride the train, I talk to customers a lot," Earl declared. "There was a guy I just started chatting with, and he said his wife and he wanted to live more in the country. They've always been in Seattle and wanted to raise their children in a more suburban-type setting. And he said the only way that made it possible was Sounder." But the greatest harm to the environment and the public comes when you calculate the lost opportunities. Much could be done to move people and reduce congestion in energy-efficient, cost-effective, health-enhancing ways, but Sound Transit is sucking up a huge share of the fiscal oxygen. Vanpools and better use of existing transit have been mentioned. Carpools are a third option. Incentives and programs to increase carpooling just a little would take more cars off the road, and save more energy, than anything Sound Transit aspires to do, and do it much faster, more reliably, with less risk. Completing the HOV system and instituting congestion pricing should be high priorities. The leading forfeited opportunity is bicycling, the best possible transportation mode: cost-effective, energy-efficient, non-polluting, and healthy – save for the danger from surrounding cars. Largely due to poor civic leadership, people are oblivious to the role of bicycles in numerous modern, European cities such as Amsterdam and Copenhagen. These cities might be flatter than Seattle and more compact, but modern bicycles and good route selection cope well with hills, and northern Europe is more afflicted with snow, ice, and cold. "Two-wheels rule the roads, it's difficult to get lost, and there are bike paths everywhere," a New York Times story about Amsterdam recently declared. "The best way to get around is by bike or on foot." A quarter-century ago, Amsterdam and Copenhagen were accumulating heavy automotive traffic, more congestion, more accidents, squeezing out bicycles and pedestrians, just like American cities. Since then, they've worked and invested to facilitate and promote bicycling and walking, reduce energy consumption and greenhouse gases, improve air quality, enhance the health of participants, and radically reduce the frequency of accidents. Much of the focus has been the provision of safe, exclusive corridors, often taking lanes or even streets that had been dedicated to (or encroached on by) automobiles. Also key is paying close attention to safe crossings, so that children, even young children, can safely bicycle to school, as most now do. In those cities, the market share of transit is six to eight times what it is here – 16 percent in Amsterdam and 20 percent in Copenhagen, contrasted with less than 3 percent in Sound Transit's domain. Bicycling outstrips transit, with market shares well beyond 20 percent and growing. Here, it's roughly 1 percent. Most local folks own bicycles, but they won't think of bicycle commuting because it's dangerous, for lack of safe routes. With a modest commitment, good planning and execution, and some of the money currently siphoned out of the economy by Sound Transit, bicycling could quickly surpass transit in market share. On March 7, City Council member Peter Steinbrueck hosted a civic forum featuring Brian Hansen, a bicycle planner from Copenhagen. The large audience got a picture of what an enlightened city can do to improve and extend bicycle commuting and, by doing so, save energy and money, reduce greenhouse gases, and improve health and safety. Not to be upstaged, especially not by Steinbrueck, four weeks later Mayor Greg Nickels announced his $240 million bicycle plan, an impressive number, although there is only $27 million in hand to support it over the next 10 years. Sound Transit compounds the bicycle imbalance by poor planning to facilitate cyclists. Recently it announced that light-rail cars will accommodate 200 passengers (by cramming them on) but only two bicycles. Two! They just don't get it.


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