Policy Brief

No discussion about regional transportation is complete these days without some reference to the impact on greenhouse gases. This is understandable because CO2 emissions from cars represent 47 percent of greenhouse gas (GHG) emissions in Washington. Light rail is frequently mentioned as a sure fire way to reduce CO2 since it runs on electricity. In King and Pierce counties, electricity is generated primarily using non-CO2 emitting sources including hydroelectric, nuclear and wind power. Given that King County light rail will emit very little CO2, it seems an obvious policy option for reducing transportation-related greenhouse gases.

A number of policymakers agree with that logic. Elected officials and interest groups have made a range of claims about the importance of light rail to reduce transportation-related greenhouse gases. On Seattle Mayor Greg Nickels’ “Mayors for Climate Protection” web page, he notes that “cities are implementing a host of climate-control strategies, adding bike paths and bus routes or light rail…” The Sierra Club agrees, saying “We need to offer commuters more buses and light rail choices…” The organization promoting the Roads and Transit Proposition 1 notes on their web page under the heading “More transportation choices means a cleaner environment,” and that “Building an additional 50 miles of light rail … will take cars off the road and provide better mobility options.”

Only Emory Bundy has questioned whether light rail will actually reduce CO2 over the course of its lifetime. He cites the high level of CO2 emissions during construction, indicating that light rail will probably not save enough CO2 on a day-to-day basis to catch up to the amount of emissions emitted during construction.

Read the full Policy Brief here