A design for a new bridge on Interstate 5 over the Columbia River between Portland, Ore., and Vancouver, Wash., includes vertical-axis wind turbines that could generate an unspecified amount of energy and possibly power the bridge's lighting and tolling. Designed by a Florida firm, the $4 billion bridge is part of a plan to ease traffic congestion. Some engineers, however, say a concrete girder design, a flat steel truss and girder design or an extradosed bridge would be less costly.

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