Bridging the global warming gap
CO2-friendly - Planners of a new I-5 span juggle ideas on tolls and prices, looking for ways to slow the growth in trips
February 24, 2008
DYLAN RIVERA
The Oregonian
Builders of a new Interstate 5 bridge over the Columbia River will have to keep from hurting endangered fish and make sure air pollution from many more vehicles stays within federal limits.
But Portland and Vancouver officials have one more worry: They want to be sure a vastly expanded bridge does not result in boosted carbon dioxide emissions that worsen global warming.
No law requires this of Oregon and Washington, builders of the $4.2 billion Columbia River Crossing. But climate change is such a concern that Northwest officials have asked that federal environmental reviews take into account how much greenhouse gas would be produced by the thousands of cars and light rail trips that would occur daily if the bridge is built.
"It is an extremely important concern for all of us," Vancouver Mayor Royce Pollard said. "Oregon and Washington should be setting an example for the rest of the country on how to be green and sustainable."
The bridge would be the largest public works project in the Northwest if construction starts in 2011 as anticipated. Under the most ambitious scenario, it would rebuild six highway interchanges, replace the existing I-5 spans with a new set of spans allowing 12 lanes for auto traffic, light rail, and wide bicycle and pedestrian lanes. Opening in 2017, the bridge would include toll charges to help pay for construction and reduce congestion. There are less ambitious alternatives, as well, though the most popular choice is for the total overhaul.
Now technicians from both states have estimated CO2 levels from anticipated traffic volumes through 2030 for inclusion in a federal study of the project due out in two weeks. But experts and politicians disagree on exactly how to decide whether the bridge project would, in fact, have an impact on global warming.
Scientists have warned the world could face catastrophic floods and other warming impacts by 2050 if worldwide temperatures continue to climb. Oregon's governor and Legislature last year agreed to cut greenhouse gas emissions by 75 percent by 2050. Gasoline-powered cars and trucks produce CO2, making the transportation sector a leading contributor to the CO2 linked to global warming.
Though the study isn't quite finished, Columbia River Crossing analysts have concluded that the new bridge would produce more net carbon but make greater volumes of traffic more CO2-efficient by removing the stop-and-go congestion now clogging approaches to the spans. Result: CO2 emissions would grow more slowly with a new bridge than if officials did nothing and let the old bridges collect yet more congestion, which causes more greenhouse gases.
That's not good enough, said Jill Fuglister, co-director of the Coalition for a Livable Future, a Portland-based sustainability group. She contends the project should reduce the amount of vehicle traffic across the bridge -- currently about 134,000 trips a day on average.
"Any transportation investment we make today . . . should not contribute to the growth in driving, which equals growth in greenhouse gas emissions," Fuglister said.
More cars a given
But automobile use will grow through at least 2030 because of population growth, no matter what happens to the five-mile corridor the Columbia River Crossing attempts to fix, said David Parisi, a transportation planner from San Francisco on contract for the project.
"No form of mass transit is going to take care of all trips," he said, referring to that part of the project devoted to light rail.
Parisi's view is shaped by a comparison of traffic volumes in 2030, given the region's population growth forecasts.
Leave the current I-5 bridge in place -- the so-called do-nothing alternative -- and the 134,000 average daily car and truck trips would grow by 37 percent by 2030.
Build the recommended overhaul -- twin six-lane bridges with light rail and high tolls at rush hour -- and the number of average daily trips would climb by 33 percent by 2030. Still, that number, while lower than the 37 percent in the do-nothing scenario, means many more cars and more CO2 emissions.
Only the combination of tolls and light rail -- not one or the other -- reduces trips below the 37 percent rate, Parisi says. They greatly help reduce traffic congestion, which reduces emissions.
"It's kind of a package deal," he argues.
"Cheapest, greenest"
Metro Councilor Robert Liberty said the region should scrap the proposal entirely. Toll the existing bridge -- and change nothing else for a while -- to see how that reduces congestion and carbon emissions, he urged. Follow up with light rail and river navigation enhancements that would be less costly than the $4.2 billion proposal on the table.
"Stage it, so we can figure out what's the cheapest, greenest way of doing it," Liberty said.
But only imposing tolls or building light rail would not address the region's concern about safety, congestion and movement of freight, said Heather Gundersen, environmental manager for the Columbia River Crossing. It could also unravel the region's political consensus for the project.
"There would be a lot of people that would be really frustrated," Gundersen said.
Dylan Rivera: 503-221-8532; dylanrivera@news.oregonian.com For environment news, go to http://blog.oregonlive.com/pdxgreen
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