On the Economics of Sidewalks

Today on the Kojo Nnamdi Show, DC residents debated the pros and cons of adding sidewalks to northwest neighborhoods that still lack them. Well, it was mostly pros, from making walking easier to complying with Americans With Disabilities act. The cons were concerned with losing what country-feel they had in the metro area and that few people actually use sidewalks that are installed.

But no one mentioned another problem with adding sidewalks, not surprising because the pros are unlikely aware of it and the cons wouldn't want to admit it: adding sidewalks increase foot traffic and make life harder on those that live there. In economic jargon, sidewalk traffic externalizes costs on surrounding residents.

Sidewalks make walking cheaper and so, no doubt, you'll get more foot traffic. That means more dog walkers, and the increased risk of the dog walker not cleaning up after her animal when he does his business. That means more children running around, and the higher likelihood of noise and damage from particularly active kids. It means more people lingering in a driveway, trampling lawns or flowers, and risk seeing you while being intimate with loved ones (sometimes you forget to close the drapes).

It sounds so selfish, but why should local residents bear the cost of other's enjoyment? The common theme when people called in is that they moved to those areas because the lack of sidewalks made it feel more rural. They were looking for one thing: isolation.

Note: For the record, I'm in favor of the sidewalks only because, in my estimation, the costs externalized onto residents with the sidewalks are likely lower than the costs which must be suffered by people because there are no sidewalks to use.