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30th Street and Colorado Avenue Redesign: Boulder Colorado is Not Ready

By Dom Nozzi

February 8, 2018

Boulder established a Community Working Group (CWG) in 2017 which was tasked with helping to redesign 30th Street and Colorado Avenue. The redesign effort was motivated by the fact that these roads are characterized by important concerns: a high level of crashes, low levels of bicycling, walking, and transit, poor aesthetics, and issues with residential and retail development along these roads.

The 30th Street and Colorado Avenue redesign should significantly improve health for small retail shops and homes. It should significantly improve safety for all users. It should beautify the corridor. It should be designed to ensure that land uses along the corridor produce sufficient taxes so that the street is financially self-sufficient (in its current state, it is a financial drain). It should, in other words, be a street and not a stroad. Unfortunately, as of February 2018, four of the six options are window dressing options that are doing nothing to advance these important objectives.

I will focus my comments on 30th Street for the sake of simplicity and brevity, but much of this could also be applied to Colorado Avenue.

With regard to mobility vs accessibility, it has become clear to me that the focus of the 30th and Colorado project is heavily tilted toward mobility. Four of the six design options, for example, would maintain the current configuration of four general purpose (GP) car lanes. I have a number of problems with the car-centered bias, and the overall project evaluation.

Including the “No Build” (existing conditions) scenario, there are six design options for 30th:

  1. No Build (existing): Four GP car lanes, bike lanes, sidewalks. Very low financial cost.
  2. Option 1 and 1a: Two GP car lanes, center turn lane, wider bike lanes with buffers, protected bike lanes for 1a, no added ROW needed. Very low financial cost.
  3. Option 2: Two GP car lanes, two bus lanes, center landscaped median, wider bike lanes protected by tree strip, 30 ft more ROW needed. Very high financial cost.
  4. Option 3: Four GP car lanes (with wider outside lanes), wider (and protected?) bike lanes, landscaped tree strip, 20 ft more ROW needed. Very high financial cost.
  5. Option 4: Four GP car lanes (with wider outside lanes), bike lanes removed, wider ped/bike shared sidewalks, 20 ft more ROW needed. Moderate financial cost.
  6. Option 5: Four GP car lanes (with wider outside lanes), wider and buffered or protected bike lanes, no added ROW needed. Very low financial cost.

Over the course of a great many meetings, the staff and consultant worked with the Community Working Group (CWG) to come up with criteria to evaluate the ability of various design options to achieve various community objectives. Unfortunately, these evaluation criteria are flawed and are missing important measures. For example:

  • No evaluation of which design options will result in the highest average motorist speeds (clearly, the four options which propose maintaining the 4 GP car lanes will result in far higher average car speeds).
  • No evaluation of which design options will result in better accessibility rather than an over-emphasis on mobility (clearly, the four options which propose maintaining the 4 GP car lanes will result in excessive car mobility at the expense of accessibility).
  • No evaluation of which design options will result in the largest number of crashes (clearly, the four options which propose maintaining the 4 GP car lanes will result in a far higher number of crashes). There are four evaluation criteria which address safety, and I find it highly misleading that the evaluation scoring shows all six design options making safety “better.” This is highly misleading because it strongly implies that all six design options will be equally beneficial in improving safety. In my opinion, this is absolutely untrue, as the four options maintaining the 4 GP car lanes will be far less safe. For example, let’s say that 10 car crashes occur each year on 30th. While it may be technically true that safety tweaks in the four options proposing to maintain the 4 GP car lanes will result in, say, 9 crashes instead of 10, the two design options which propose 2 GP car lanes will result in, say, 2 crashes instead of 10. Clearly, the 2 GP car lane design options are far safer, but again, the evaluation implies they are all equally beneficial for safety by labeling all of them as “better” for safety.
  • No evaluation of which design options are most conducive to more compact, accessible, walkable, bikeable, transit-friendly retail and residential land use patterns (clearly the four options which propose maintaining the 4 GP car lanes are far less conducive to such retail and residential development along 30th).
  • No evaluation of which design options are most likely to promote an increase in walking or bicycling or transit travel (clearly, the four options which propose maintaining the 4 GP car lanes will result in far fewer walking or bicycling or transit trips on 30th).
  • No evaluation of which design options are most likely to advance Boulder GHG emissions and climate change goals (clearly, clearly, the four options which propose maintaining the 4 GP car lanes will result in far higher emissions and failure to meet climate change goals).
  • No evaluation of which design options are most likely to advance the Boulder Vision Zero goal (clearly, only the two options which propose to establish 2 GP car lanes have any realistic chance of achieving Vision Zero).

The four design options which propose 4 GP car lanes (No Build, and Options 3, 4, and 5) are exceptionally unsafe for at least three reasons: (1) They induce far higher average car speeds than do Options 1 and 2 (and the speeding driver sets the pace, rather than the prudent driver); (2) They induce frequent lane changing by cars, which is extremely dangerous at higher speeds; and (3) They induce more inattentive driving (due to the large width and relatively low level of “friction”). On the issue of speed, studies have found that the probability of death in a car crash at 20 mph is about 5 percent. At 30 mph, the probability is about 45 percent. At 40 mph, it is 85 percent.

It is now acknowledged by a large and growing number of American traffic engineers (including the US DOT) that a 3-lane road (which is the configuration for the two proposed “2 GP car lanes” design options on 30th ) carries about the same volume as a 4-lane road. That, in addition to the rather large number (and significant) benefits that converting from 4 GP car lanes to 2 GP car lanes delivers, helps explain why City of Boulder staff supported the “2 GP car lanes” design option a few years ago for 30th. The reason 3 lanes carries about the same as 4 lanes is that like on 30th, when there are many left turns not supported by a left-turn lane, the inside lane of a 4-lane road behaves as a 3-lane road because the inside lane is regularly acting like it is a turn lane.

Some on the CWG objected to the evaluation criterion of “reliable” travel times. The thinking of those who objected was that this did not capture the overwhelming objective held by most Boulder residents: That travel time not be increased by a design option. I pointed out that we must first define what we mean by “increased travel time.” Is one additional second of travel time considered unacceptable (in exchange for far fewer car crashes)? Is five seconds unacceptable? How about three minutes? Without defining what we mean by an unacceptable increase in travel time, I don’t believe it is a good idea to change this criterion from “reliable” to an “increase in travel time,” as some CWG members suggested. Personally, I don’t believe it is possible for Boulder to come up with a community-wide, agreed upon definition for what is the unacceptable threshold for increased travel time. In part because there are so many trade-offs (safety, promoting bicycling, retail health, etc.).

In sum, of the six proposed design options, only the two options which propose 2 GP car lanes (Options 1 & 2) have any chance of achieving land use, transportation, climate change, or safety goals adopted by Boulder. Besides the “No Build” option, the other three options which propose 4 GP car lanes (Options 3, 4, & 5) are essentially also “No Build” options with window dressing such as added landscaping or wider bike lanes. In part, these three are “No Build” options because they do almost nothing to advance Boulder objectives. In addition, as Charles Marohn has pointed out in his work for strongtowns.org, the four options which maintain 4 GP car lanes impose a severe and unrelenting financial burden on Boulder because they induce high car crash and maintenance costs, as well as inducing land uses which do not produce taxes that are high enough to support the costs they impose.

For the record, I support Option 1a (2 GP car lanes, center turn lane, and protected bike lanes).Road-Diet

It should be noted that in the scoring of the six design options by staff and the consultant, Option 2 (2 GP car lanes and two bus lanes) scored far better than any of the other options. Curiously, at the January 22nd CWG meeting, nearly all CWG members indicated a preference for one of the three “No Build with Window Dressing” options (4 GP car lanes). Option 3 was particularly popular. Tellingly, even though these three “No Build with Window Dressing” options were by far the most popular among CWG members in attendance, there seemed to be great reluctance for anyone to speak up and explain the benefits. My speculation as to why the three “No Build with Window Dressing” options were preferred by most, then, is either that CWG members were looking out for their own personal interests (despite being told up front that community interests should take precedence over personal interests), or that CWG members were considering the reaction to the Folsom Street project and deciding that the political winds would not make Options 1 or 2 viable.

As I have pointed out previously, I don’t believe Boulder is politically ready to adopt a design option for 30th that will meaningfully achieve a great many important community objectives. I therefore believe that Boulder should suspend this project until such time as the residents of Boulder are politically willing to support a design that is effective in achieving community objectives. Proceeding under existing political conditions wastes time, effort, and money.



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It Must Be the Fault of the Pedestrian

By Dom Nozzi

October 7, 2017

A century ago, as Peter Norton points out in his book Fighting Traffic, nearly all of us would blame a motorist in a crash that injured or killed a pedestrian or bicyclist.

But today the situation is reversed.

The knee-jerk response in our age is to blame the pedestrian. To blame the victim. It is akin to blaming a woman for being raped because she dressed “too provocatively.” Or was walking alone at night.

In the very rare instances when a community decides to use effective tactics to reduce the number of times a motorist kills a pedestrian (by, for example, designing the street to obligate slower, attentive driving), many motorists will scream “WAR ON CARS!!” This creates an enormous political obstacle to the creation of a safer transportation system.

Such WAR ON CARS! screamers conveniently forget that tens of thousands of pedestrians are killed by motorists every year. And that not a single motorist has ever been killed after being hit by a pedestrian.pe

Sounds more like a war on pedestrians to me…

I refer to “effective” tactics to improve safety, because nearly all US cities are guilty of spending the past century using, over and over again, ineffective tactics: More safety signage. More safety lighting. More safety paint. More safety education. And more safety enforcement.

Since our roads are now more dangerous than ever following a century of repeatedly doubling down on those ineffective tactics, maybe it is finally time to realize that these conventional safety tactics are a failure.

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Are Cell Phones the Main Cause of a Recent Increase in Traffic Fatalities?


By Dom Nozzi

April 1, 2017

It is surprisingly difficult to isolate causes of crash/fatality trends in driving. One source has made the persuasive case a while back that the only good correlation we can find is based on the health of the national economy, of all things.

In any event, pointing to something like cell phones is a “pay no attention to the man behind the curtain” method that distracts people from a major cause of crashes: our roads are shockingly dangerous in how they are designed. And this follows over 100 16598647019_2c1634cb89_zyears of annual campaigns to make roads safer. Talk about a failed track record. Talk about a need to change course on our efforts to improve safety…

The US has seen over 30,000 people die on the roads EACH YEAR since the 1940s. Cell phones did not arrive until the 80s or 90s. The number of annual deaths is a crazy high number and should be utterly unacceptable to any civilized society. Given the American love of the death penalty, our failure to adopt universal health care, our 240 years of being a Warrior Nation, and our abusive criminal justice system, a great case can be made that the good old USA is one of the most uncivilized nations in human history (probably at least partly due, ironically, to our high level of religious belief – which is infamous for inspiring hatred, violence, and intolerance).

I agree that cell phones (and many other distractors) are very dangerous for a driver to engage in while driving. But we need to keep our eye on the ball. We’ve had over 100 years of failed efforts to make driving safe.

In sum, if no driver ever used a cell phone again, we’d STILL be seeing over 30,000 traffic fatalities in the US each year.

In my view, successfully reducing the number of drivers distracted by cell phone use is unlikely to produce the safety benefits we expect. Efforts to point to cell phones as a silver bullet solution to making our roads significantly safer is quite likely to distract us from the much more important, pressing fact that our car-happy transportation system is inherently deadly (largely due to car-happy, “forgiving” road design and a dispersed land use pattern that requires us to drive everywhere — and at high speeds).


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What Do I Think of the Diverging Diamond Interchange?


By Dom Nozzi

Febuary 2, 2017

Superior, Colorado built a “diverging diamond” interchange that opened in October 2015. It was only the second such interchange to ever be built in Colorado. Traffic engineers are imagessinging its praises throughout the nation. A newspaper article appearing in the February 2, 2017 edition of the Boulder Daily Camera fawned over the fantastic new addition to the region’s transportation system.

I am not joining the engineers or the newspaper in their love affair with the design.

Instead, I find such designs a colossal waste of money – money that could have been used for, say, transit. They are also a colossal waste of land. An entire city could fit inside one of these intersections.

The diverging diamond is a boondoggle for those reasons. But it is also a blunder because they promote increased per capita car travel. Why? In part because they are nearly 51df393d218c6-imageimpossible to cross by foot or bicycle. And in part because in the long run they will further disperse land development in a more sprawling way. Those increased distances will make it increasingly impractical to walk, bicycle or use transit.

Ironically, the major justification for the car-only design is that it briefly reduce intersection congestion, which will initially save a few seconds of motorist time (think of the fiscal irresponsibility of spending millions of public dollars spent to save a few seconds temporarily). Ironic because by artificially inducing more car trips than would have occurred had the diverging diamond not been built, the design will lead to MORE traffic congestion and MORE time delay for motorists in the long term (both at their location and areas in the region).

To hide the embarrassing fact that the millions spent ($14 million in this case) to briefly save a few seconds of time, the publicly proclaimed explanation is that it will improve safety. For the conventional traffic engineer, “improved safety” actually means that motorists can now drive faster and more inattentively with less fear of crashing. No mention is made of the fact that the intersection is much less safe for pedestrians or bicyclists, or that faster, less attentive driving is very dangerous for everyone.

The diverging diamond, therefore, is an excellent example of the century-long failure by conventional traffic engineers to understand induced car trips that are created by (briefly) reducing traffic congestion with these designs. There is a reason, after all, that many researchers repeatedly urge us to understand that it is impossible to build our way out of congestion. It is like loosening your belt to solve obesity.

But wait. There’s more.

Not only is the diverging diamond a boondoggle in the above mentioned ways. It also damages our world by adding more auto emissions into our air (by increasing per capita car trips) and reducing potential tax revenues in the region (by encouraging dispersed rather than compact land use patterns).

Future generations will shake their heads in disbelief over why our generation built these monstrosities.

There is one tiny upside to this overwhelmingly negative idea: it produces future jobs for people hired to remove these mistakes after we regain our senses.

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The Undesirability of Autonomous Cars

By Dom Nozzi

December 16, 2016

Autonomous cars remind me of the many techno optimists in the 60s and 70s who assured us that we would soon be driving flying cars like The Jetsons.jetsons

So much faster! End of traffic jams! No air pollution!

Assuming autonomous cars become a significant part of our lives — which is highly unlikely given enormous difficulties associated with making autonomous vehicles work in the real world — such vehicles are likely to create a great many negative unintended consequences.

First, there will be a huge increase in per capita car travel due to the relative ease of car travel by such vehicles. Many trips that were formerly made by walking/biking/transit (or not at all) will now be by car — including by kids, the handicapped, and seniors who are now unable to drive.

Second, there will be a need for wider roads to handle that per capita increase.

Third, we will see higher average car speeds.

Fourth, we will see more pedestrians and cyclists killed by cars since the software will direct the car to kill such people rather than the driver.

Fifth, there will be a big increase in obesity due to the increased amount of travel by car.

And finally, we will suffer from a perpetuation of unsustainable transport energy consumption, toxic air emissions, and dispersed land use patterns.

uber-carOverall, like standard cars, autonomous cars are extremely toxic to cities. To be healthy, cities require slow speeds (which promote the agglomeration economies that cities require). Higher speeds induce more low-density dispersal, which destroys city health and the essential need for social capital. Cars isolate us, yet our genes and our cities need interaction.

In general, autonomous cars are a solution looking for a problem.

Given the consequences I mention above, we need to hope that autonomous cars are as “successful” as George Jetson’s flying cars. I’m not worried because I am confident autonomous cars will soon be forgotten.

What bothers me most is that such pie-in-the-sky vehicles distract us from pressing city and human needs we have neglected and failed to address for several decades.

How much progress have we made on passenger rail design and implementation, for example?

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Promoting Traffic Safety


By Dom Nozzi

August 20, 2016

After three years of trying, I have finally been given the opportunity to give a presentation to the Boulder transportation advisory board – of which I have been a member. The topic will be on traffic safety, and I will be making the presentation in either early September or early October.

I decided one point I’d like to make is that if anything, streets have become much less safe than they were in the past – despite decades of often aggressive, extensive, expensive boulder-traffic-safetysafety efforts. This morning, I looked for a chart showing the trend in the number of annual deaths on US roadways. I have included a few charts from Wikipedia in this blog. “Annual Traffic Deaths” shows the crazy high number of annual deaths.

But the “Annual Deaths Per Mile Driven” chart shows that we are making a lot of progress on safety! I was surprised and realized I’d have to revise my presentation.

Then I came across a “Traffic Deaths” essay.

I learned from the essay that several decades ago, the auto folks needed to find a way to address the great alarm on the part of many Americans when they saw the huge number of traffic deaths. The solution to this PR problem – to head off serious efforts to reduce car dependence in our society – was to convey deaths based on MILES DRIVEN. It turns out that applying “miles driven” as a way to measure deaths is quite misleading. After all, if we used miles traveled, the space shuttle would be the “safest” way to travel…

Using that metric, the auto folks were able to reduce alarm (and meaningful efforts to reduce car dependence), because the metric shows improving traffic safety. Now we can sidestep the thought that 30,000 to 40,000 traffic deaths per year is barbaric (and demands our society reduce car use) and instead focus safety on individual motorist mistakes or mechanical solutions (which does almost nothing to correct this shocking, unacceptable road carnage problem).

One of my points about traffic safety is that our forgiving roadway design induces dangerous and growing levels of inattentive driving and excessive speeding. I believe inattentive driving and speeding are epidemic mostly because of our decades of employing forgiving roadway design. But if this is true, why does the chart show a decline in deaths since 1970?

My explanation is that while roads ARE more dangerous today than in the past, much of the reduction in deaths is associated with making cars (and, therefore, the motorists bike-car-crash1inside them) safer with such things as seat belts, air bags, and aggressive efforts against drunk driving – not to mention our removing a lot of trees and other “hazards” from near the side of roads.

I found another chart that shows a big increase in bicyclist deaths since the 1970s. That can partly be explained, I guess, by the growth in cycling since then, but I think it is also compatible with my belief that roads are more dangerous today. Motorists are safer in certain ways, but the growth in inattentiveness and speeding are leading to motorists killing more people bicycling.

In sum, it is clear to me that our roads need to be substantially redesigned to obligate slower, more attentive driving by motorists through various traffic calming, as well as reductions in the size of roadways and intersections. More warning signs, warning lights, warning paint, warning education, and warning enforcement has utterly failed to make our streets safe.

It is way past time to get serious and redesign our appallingly dangerous roadway system.

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The Perversity of American Subsidies

by Dom Nozzi

It is perverse that the US government so heavily subsidizes and provides for a form of travel (car travel) that is largely or fully responsible for…

About 45,000 deaths (not to mention the injuries) per year

The destruction and abandonment of so many US town centers and their quality of life 

The bankrupting of households and all levels of government

Suburban sprawl

The obesity epidemic and associated health problems

Enormous dependence on foreign oil produced mostly by nations that dislike the US

The gigantic and on-going loss of important wildlife habitat

The loss of peace and quiet

The huge loss of human interaction with their fellow citizens (we have become a nation of loners)

The loss of civic pride as a result of the homogenizing, strip commercial transformation of our communities

The diminishing returns that promotion of car travel now provides

The loss of small, locally-owned businesses

This is a recipe for societal dysfunction.

I believe so few of us are pointing out this elephant in the bedroom at least in part because we believe, mostly accurately, that our lives are impossible without cars, so we put ourselves in a gigantic state of denial with this Faustian Bargain.


Visit my urban design website read more about what I have to say on those topics. You can also schedule me to give a speech in your community about transportation and congestion, land use development and sprawl, and improving quality of life.

Visit: www.walkablestreets.wordpress.com

Or email me at: dom[AT]walkablestreets.com

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