U.S. develops parks above highways

In big cities, finding land for new parks is less of an expedition than an all-out land-rights battle with property owners. But some cities across the U.S. have found a slightly easier way to add to their greenspace. By utilizing the state's air rights to the space above freeways that run below at ground level, cities can acquire 5 or 10 acres of parkspace essentially for free, such Freeway Park which occupies 5.5 acres above a freeway in downtown Seattle.

Of course, this free "land" is actually nothing more than open air above a freeway, requiring cities to pay the high construction costs of capping the roadway with land.

Such projects are currently being planned in St. Louis, Cincinnati, Dallas and San Diego. A recent article in Governing Magazine looks at more than two dozen highway deck parks that have been built or are under construction in the U.S. The article finds that even though the price of constructing parks on top of freeways can rise upwards of $500 per square foot, property values and local development boom once they are completed.