Traffic is a problem all over America. In our urban centers, traffic causes noise pollution as well as actual pollution and wastes time, money and resources. In a word,. Even in cities that were designed around the automobile, like Los Angeles, the sheer number of cars on the road forces municipalities to make infrastructure decisions that can make life for pedestrians and cyclists miserable.
On Friday a group called Sidewalk Labs published a document outlining what it thinks the four principles of modern street design should be and some of the ideas are pretty wild. Others just make too much sense to ignore.
The first principle that Sidewalk Labs suggests is that different streets should be tailored specifically for different roles. This means that there would ideally be streets for pedestrians and cyclists only, streets for regular cars, streets for transit and streets for autonomous and connected vehicles.
In some ways, this is a good idea. Each mode of transportation has different needs, some of which are mutually exclusive. Cars, for example, need more space and that space can't be shared as easily or safely with pedestrians. On the other hand, streets that prioritize above-ground light rail -- like Portland, Oregon's streetcar system -- don't necessarily jibe well with cyclists but would be fine with cars or pedestrians.
The second principle being put forth is that streets should be separated by speed. This means that the bigger and wider streets would handle the transit and vehicle traffic, but there would be less of them, so the distance traveled would be greater.
Pedestrian-focused "laneways" would be more common, so the physical distance traveled would be much less, but the speed of travel for someone on foot is very low, so the time spent en route wouldn't be dramatically different from that of other modes of travel.
The Labs' third principle of design is that urban planners should incorporate flexibility into street space. This would be done with something called dynamic pavement. This is another name for pavement with lots of LEDs and sensors in it that could be programmed to show different markings at different times.
For example, during low-traffic density hours, a street typically geared toward bikes and pedestrians might be temporarily restriped to offer parking to cars. Those cars aren't moving quickly, so the narrower, slower street type wouldn't restrict them too much. Open parking spaces could be lit up to help cars find them quickly. When demand changes and parking isn't as much of a priority, the road markings would change.
This is something that is done on a more limited basis now but by using street signs. For example, in downtown Los Angeles, the lane closest to the curb is usually designated as a parking lane, but during peak traffic hours, parking isn't allowed, and that lane is used to lessen the overall density of cars on the road, hopefully speeding up traffic. Being able to change markings dynamically would bring a lot more flexibility to bear on the problem of traffic.
The fourth and final principle that Sidewalk Labs suggests is likely to be the most controversial to motorists. It advises that the city "recapture street space for the public realm, transit, bikes and pedestrians."
What does that mean? This principle takes the other three principles and wraps them all up together. It suggests that most of the space devoted to cars and parking be removed and repurposed for pedestrians, cyclists and public transit to make the city more livable and pleasant.
The problem with this idea, in our opinion, is that it can make access to businesses or residences difficult or impossible. What if, for example, you live in the middle of a busy downtown center -- we'll use Los Angeles as an example again -- and you have a vehicle that you park underground.
Your building is hemmed in by a pair of streets that get redesignated as a "laneway" and an "accessway" so that means that getting your car out of the garage and out of downtown becomes infinitely more complicated and time-consuming. Ditto if you are coming into downtown with a car because you live somewhere with limited access to transit and you need to go to a doctor's appointment, but that doctor's office is on a street designated as a laneway.
A lot of these ideas will make more sense when the ratio of human-driven cars versus autonomous cars shifts in favor of autonomous vehicles, but that is years if not decades off. Until then you'd have to rely on people to understand and obey these new kinds of traffic control ideas and devices.
All that being said, it's one of the more interesting -- and in some ways at least -- practical looks at how to reimagine the way we use our city streets. We've seen time and again that infrastructure as it exists now and as it is traditionally built has difficulty meeting the needs of an increasing population that is increasingly mobile. Maybe Sidewalk Labs is on the right track toward finding a solution.