Tuesday, March 27, 2007

Improving the highways

Here are some more thoughts on how to improve the transportation system in San Diego, or anywhere. Since we obviously aren't going to have massive public transportation infrastructure appear overnight, and since it will probably take many years for something like that to come to fruition, I have been thinking about how me might improve the system that we DO have in the mean time. My thoughts have been on function, aesthetics, publich health, and environment.

I haven't come up with much for function (see my previous post on public transportation for those thoughts), but for the other three I have a good idea inspired by Lady Bird Johnson. As you may or may not know, freeways produce corridors of pollution that hover over the interstate system for a width of about two miles on either side, causing increased risk of respiratiry problem for people (especially children and elderly) who live within two mile of any major freeway. For most cities, that reaches a great number of residents. Also children who attend school within those miles are also at risk, as school is where they spend so much of their time. And of course work within 2 miles exposes adults, though adults are at less of a risk of implications. Still, who wants to be haning out in the corridor of pollution?

The main idea is to line all the freeways with large, fast growing plants. This can mean trees if they are put in large enough to reach very high, or creating walls on the sides of the freeways that can be coered with thick vines. Bamboo would also do the trick as it grows incredibly fast and gets very tall. There should, of course, be an emphasis on native plants when possible, and always on low-water plants, especially in arid and semi-arid environments.

This would offer a sound barrier between the freeway and the rest of the world, and would also beautify the freeway sights as we drive down it. I'd much rather look at plants than fast food and gas station signs anyday. And from the city I'd much rather look at plants than a lines of speeding cars.

It would also offer the benefit of absorbing carbon dioxide and other pollution as it emerges form the highway. I don't know how effective this would be. I've never seen or heard of a study being done to this end. But I hypothesize that it would have significant effects in decreasing the pollution that would otehrwise spread out to the city.

Along these same lines, when the freeway is lower than the surrounding city, parks should be built over the freeway. Again, this would reduce noise, beautify the city and freeways, and this also create more public space. I know this is being done in San Diego; there is an existing park over the I15 in City Heights, and one planned over the 94 freeway in South Park.

And when the freeway is level with or even higher than the city, simply canopies could be built over the freeway to house lightweight native plants. These don't have to be built to support raods or people, simply a layer of plants. This owuld not only offer the benefits as the other greening options, but along with the parks this would reduce the heat generated on the freeways by the sun. How much more stressful does sitting in traffic on a hot, sunny day feel compared to a cold, cloudy one? Akin to the new movement in rooftop gardens to help regulate city temperatures, the canopies would provide shade to the freeway and the greenery would absorb heat, decreasing the temperature in the summer and overall regulating the temperature.

1 comment:

AlegraMarcel said...

Did I mention that the plant lined highways would feature native plants? All native plants. Only native plants.