USAToday had a trend story yesterday about cities that have created parks and pedestrian-friendly spaces on top of highways.
In cites such as St. Louis, Los Angeles, and my very own Big D, these green freeways are helping downtown revitalization efforts.
Transportation departments are not opposed as long as the plans don't reduce highway capacity. In most cases, traffic is rerouted.
"It's the coming together of people wanting green space and realizing that highways are a negative to the city," says Peter Harnik, director of the Trust for Public Land's Center for City Park Excellence. "Covering them with green space gives you a wonderful place to live and work."
The story also adds that developers and environmentalists are pushing for so-called decking for different reasons: developers see a way to add more prime real estate to the downtown market while environmentalists hope to offset emissions and reduce reliance on cars.
Also, my favorite part, one of the sources quoted compares highways to a medieval wall.
For more, and to see the specifics of several similar projects around the country, click here.