Urbanism 101: The benefits (and drawbacks) of one-way city streets

What do you think of one-way streets? You’ve probably never put much thought into the question before — aside from maybe some mild annoyance driving all the way around a block to get somewhere a few feet away up a one-way street — and that’s OK. The virtue of one-way streets may not be the most pressing issue facing society. But these are the kinds of questions that get urban planners going, and they make a significant, if subtle, difference in how we work and live in the city every day.

What are the benefits of one-way streets? One-way streets can improve the flow of motor vehicle traffic throughout an urban area. We often see one-way streets used in denser urban areas where there isn’t enough room to accommodate a major two-way street. Good examples in Denver would include the one-way pairs of 18th and 19th streets in Downtown Denver, and 13th and 14th avenues in central Denver. In cases like these, there’s insufficient right-of-way width to put in a six- or eight-lane two-way street (like Colorado Boulevard) so, instead, these one-way streets with three or four lanes each work together as a pair to create, in effect, a six- or eight-lane two-way street separated a block apart.

These one-way street pairings help motorists move more quickly from Point A to Point B. Have you ever noticed that when you’re driving on a one-way you feel empowered to drive a bit faster? By their design, one-way streets exclude oncoming traffic, which reduces potential danger or delay from cars turning left in front of you. Everyone is going the same direction as you are, so it feels safer and therefore you feel comfortable driving faster.

So what’s the downside? The answer was already mentioned in the paragraph above: people driving their vehicles faster in urban areas. If you’re not in one of those fast-moving vehicles — a pedestrian or bicyclist — those cars whizzing past you at a speedy clip pose a danger to your personal safety. Those drivers are too busy making good time on their quick journeys across the neighborhood to pay much attention to non-motorists. In areas where pedestrians and bicyclists abound, one-way streets are often a major hindrance to everyone other than motorists.

One-way streets were all the rage back in the mid- and late-20th century. Dozens of two-way streets in Denver’s urban core were converted to one-ways, giving us a confusing maze of one-way streets intersecting with other one-way streets that baffle all but the most experienced Downtown drivers and make it difficult for bicyclists and pedestrians to cross a street that doesn’t feel like a major highway. Fortunately, Denver is now on a path towards converting some of Downtown’s one-way streets back to two-ways to improve the safety and ambiance for those outside the comfort of a two-ton mobile metal machine. Wazee Street and Glenarm Place are recent one-way-to-two-way conversion examples, and more are to come. East 19th and 20th Avenues between Lincoln Street and Park Avenue, 18th Street between Wynkoop and Blake, and stretches of Welton and Curtis streets are currently being evaluated for conversion to two-way streets. Even more streets in the Downtown area are likely to be studied in the near future for conversion to two-way status.

Two-way streets slow drivers down, given the increased complexity of the surrounding traffic flow. Slower traffic means a safer environment for pedestrians and bicyclists (and even motorists), which is paramount in an urban area, even if it means that it might take motorists a few extra minutes to get across town.