I would like to green the streets.

Traffic through residential streets is often quieted using speed bumps, but some cities have begun using barriers and legal restrictions to do so more forcefully. A common tactic is to install concrete planters in intersections, cutting off diagonal traffic and forcing oncoming cars to turn a particular direction. This led me to wonder: What if those planters expanded, and took over a significant amount of pavement?

I'd like to see more streets made one-way, one lane, with barriers enforcing a winding path, and blocks of diagonal parking in the remaining space. This would mean a significant area of green space near the (very sunny) middle of the road. The raised planter beds could be used as a community garden.

If possible, I'd like to start this on my own street, which has some unique advantages:

1. a lively community of politically, culturally, and socially active neighbors
2. neighborhood dissatisfaction with traffic, parking hassles, and the aesthetics of cities in general and our street in particular
3. close enough ties to the local college town that everyone is familiar with related ideas for traffic and for food
4. located outside of that college town, so that constraints are more often economic than political, and tend to be more solidly rooted in reality

I'm not so sure about the legal requirements or implementation details, but I think it's more likely to satisfy more people than a few of the ideas I've heard floated lately, including parking permits and tearing up the whole street to plant in the soil underneath.

It would be nice to have a garden that looks nice as well as producing food, and thankfully there have been some amazing efforts with that goal in mind.

My (wildly optimistic) vision of the planters themselves has them about three feet tall, and made from locally-available re-claimed materials. One tentative thought is to use strips of tire tread, plastic fry-grease jugs, and demolition waste. There's enough free firewood and clean dirt listed on Craigslist to make literally tons of terra preta, if my neighborhood starts composting locally rather than filling green bins for Waste Management. I'm also thinking of a system to pump water from the gutters into the aforementioned plastic jugs during the wet season, for electronically-controlled irrigation later in the year, although that would require some special attention to keeping the pavement clean.

I'd like to hear what people think about this idea. It would be a lot of lobbying and even more manual labor, so it would be nice to hear as much criticism as possible, as early as possible. Even better would be if some other neighborhood would find all the pitfalls: if you've done something similar, or want to steal the idea, that's fantastic.