A measure that pushes the use of electric cars and the construction of plug-in stations across the state passed the Legislature today and now goes to the governor for final approval.

The bill is considered a crucial element in the state's interest in transforming Interstate 5, from the Canadian border to Mexico, into a "green freeway." Here's an earlier story about the green freeway proposal.

House Bill 1481, sponsored by Kirkland Democratic Rep. Deb Eddy, passed the House 65-29. It passed the Senate earlier. The bill requires state agencies to transition 40 percent of its fleet into running electric or biofuel vehicles by June 1, 2013. By the end of 2015 the state must install electrical charging outlets in its fleet parking and maintenance facilities.

The bill also authorizes local governments to adopt incentive programs to encourage the retrofitting of existing structures with outlets capable of charging electric vehicles. The measure also provides tax incentives for the creation of an electric vehicle infrastructure.

Jeff Doyle, director of public-private partnerships at the Washington State Department of Transportation, has been working with the Oregon and California transportation departments for months in developing the green freeway plan. Under the plan, which is supported by Gov. Chris Gregoire and her counterparts in Oregon and California, motorists would eventually would be able to stop at a number of rest stops to charge, or swap out, their electric-vehicle batteries or fill their tanks with biodiesel, ethanol, hydrogen or compressed natural gas.