DENSITY ADDENDUM: Matt provides a useful addition to my post on congestion pricing. He notes, "It's absolutely impossible to discuss transportation or planning issues in the Greater Washington area without pointing out that it would be a really, really good idea to facilitate higher-density construction in the District." Absolutely. While increasing density would not necessarily mitigate congestion on its own, it would make mass transit a more viable alternative. And, for a variety of reasons, higher density is more energy efficent and causes less environmental damage. It also seems to be good for economic development (hence all the high-rises springing up across the river in Arlington.) While not every city is bound by D.C.'s height restrictions, many have zoned for lower-density by instituting parking requirements and such. Changing this would be at least as valuable in reducing harmful emissions and the stress of long drives as introducing congestion pricing. --Ben Adler
