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Opinion: 20 may be plenty, but it’s not much help, either

Better design, not slower speeds, is the key to making Denver streets safer

An ordinance reducing the speed limit from 25 mph to 20 mph on unstriped residential streets in Denver recently was approved by City Council under the rubric “20 is plenty”—a pretty catchy slogan, but much ado about very little. Yet, it’s going to cost $1.3 to $1.5 million to implement.

Allan Ferguson

It’s true, speed kills. But a 20 mph limit just sets people up to break the law. Moreover, the ordinance would apply to only about 7% of Denver’s streets. So, that’s fine, but it accomplishes next to nothing. According to the transportation department’s own study, the problem with traffic deaths in Denver is not found on quiet residential streets.

The prime sponsor of the ordinance, Councilman Paul Kashmann, has said most drivers obey the current 25 mph speed limit — or very close to it. Some irresponsible people drive too fast; “20 is plenty” will not change that fact of life. 

Meanwhile, Denver’s Department of Transportation and Infrastructure has a long record of ignoring basic measures that demonstrably improve traffic flow, calm traffic, and/or improve safety while lowering toxic emissions from vehicles. Here are a few of them:

READ: Colorado Sun opinion columnists.

Flashing red/amber lights at signalized intersections after peak traffic hours. Hundreds of relatively lightly-traveled intersections throughout the city could be programmed for flashing red and amber lights to keep traffic moving while improving air quality and saving time and fuel. These can be either four-way red lights or two-way red lights with amber cautionary lights on the busiest branch of an intersection. 

No one needs to be sitting in a vehicle, let’s say at 9 p.m. or 10 p.m., waiting for a light to change for up to 30 seconds with no other vehicle in sight. That is environmentally unfriendly, a waste of time, fuel, and money. Currently, the number of flashing lights — “after hours” or otherwise — in Denver can probably be counted on one hand.

Roundabouts. Informed traffic engineers know that roundabouts slow traffic, keep traffic moving, improve safety, save drive time, and save fuel by eliminating stopping and starting. For some reason most traffic engineers over the years have concluded that Americans are incapable of negotiating a roundabout. Anyone who has driven in Europe or parts of New England knows that roundabouts work well and can be easily mastered.

At a recent community meeting, a representative from Denver’s transportation department said “Roundabouts require a lot of space.” That is not true.

Roundabouts do not need to be reserved for large intersections or new developments. One-lane roundabouts in residential areas are common in progressive cities like Seattle, Boulder, and Carmel, Ind.

“Rotaries” featuring trees, floral plantings, and sculptures are traffic-calming, efficient, eco-friendly, and attractive.

Denver drivers should not have to pause at a stop sign every two blocks on residential streets. Instead of changing out speed limit signs, Denver should be removing stop signs.

High-tech smart streets. It’s a big subject with lots of moving parts but, essentially, it amounts to motion-sensitive and light-sensitive technology applied to traffic control.

The old saw applies: “If we can put a man on the Moon, we ought to be able to use technology to manage traffic flow.” Fixed light-timing amounts to antiquated thinking. Dynamic light-changing can be managed with available technology.

Low-tech, modest speed bumps. Speed bumps do not have to deliver bone-jarring shocks to a driver and a car’s suspension. Mild to moderate speed bumps can do wonders to slow traffic, especially in residential areas where the council is imposing a 20 mph speed limit.

All these traffic-management techniques are far more important than the slogan “20 is Plenty.”

As for the $1.3 to $1.5 million, here’s one idea: Denver could fix a lot of sidewalks in my part of town — or any part of town — with that kind of money!


Allan Ferguson, of Denver, is author of “Route 36: Ohio to Colorado—America’s Heartland Highway.”


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