A New Vision Zero for St. Paul: Part 3 – Engineering

Part two of “A New Vision Zero for St. Paul” was about the first of the “Five E’s”: Evaluation, which very quickly led to rudimentary Engineering solutions simply to gather data and attain target goals for a transportation plan. Engineering is the second of the “Five E’s”, and often the most contentious, as it often controls what people can and cannot do within a transit system. The topic alone is broad enough to fill more than the volumes it already inhabits, and with that in mind this post will only touch on a few modest suggestions for St. Paul to aid in attaining the goals of Vision Zero.


Vision Zero operates under the assumption that humans are not naturally, evolutionarily, equipped to safely operate motor vehicles in the manner and at the speeds that our infrastructure has been built to encourage, which is why 30,000 people die on American roads every year. No enemy force has been that successful at killing people since the great wars of the mid-twentieth century. It is equivalent to a large passenger jet falling out of the sky almost every other day, a state of affairs that we would never tolerate. The system itself must be re-engineered to scale appropriately for human limitations and capabilities.

  • 25 mph.

Courtesy of guide.saferoutesinfo.org (Safe Routes to School)

Any street in which pedestrians are exposed to vehicular traffic in order to cross a street…i.e. without a protected bridge or other isolated crossing, the speed limit should be capped at 25 mph. This change could also make Saint Paul’s policy of treating every corner as a crosswalk an actual reality, instead of the fantasy it currently is. Recently, Saint Paul made an effort to change the speed limit on Cleveland Ave to 25 mph, but the effort was thwarted by the county.

Courtesy of nyc.gov.

At speeds of 25 mph and under, stopping distance improves by 23% over 30 mph and fatalities are substantially reduced. Furthermore, the speed is low enough that drivers have the opportunity to see – and stop for – pedestrians. The excuse “I didn’t see them”, which is often invoked for failure to stop, is actually, technically true. At speeds faster than 25 mph, human beings are not capable of ensuring that their vehicles – their lethal weapons – are being employed safely and responsibly. In other words, traveling faster than 25 mph in a pedestrian-permissive environment is, by definition, traveling too fast for conditions. The next driver to hit a pedestrian might cynically argue in court that the infrastructure and laws were built in such a way to compel him/her to exceed his/her capabilities.

USAF installations have adopted 25 mph, (and 15 mph in most residential areas), because the data is overwhelming regarding pedestrian survivability, and because Wing Commanders are tasked with safeguarding their Airmen, civilians, and families. Whether drivers are irritated about slowing down never enters the calculus, because of the overriding concern for life. Cities are supposedly tasked with the same, and yet care too much about the convenience of drivers.

Images courtesy of NACTO


Saint Paul should join New York City, Boston, Los Angeles, Washington D.C., London, Berlin, and Tokyo in implementing this Vision Zero policy goal. Even cities in, of all places, TEXAS, are considering 25 mph limits.

When I first moved here, there were a lot, but a lengthy ride around Saint Paul revealed that they are all gone. An entirely disappointing Star Tribune poll indicates that 83% Minnesotans oppose 25 mph speed limits. So we apparently prefer speed over life, and also favor distracted driving.The “debates” on social media regarding the latter were depressing in the depths of ignorance they attained.) If policymakers and the public are unaware of the incontrovertible human factors research and survivability data, it represents a staggering gap in Education. But if they are aware, and simply choose to ignore it, keeping speeds high or neglecting to build pedestrian protections is a grotesque ethical failure. Amorality is the state of not possessing a working knowledge of the difference between right and wrong, while Immorality is knowing, and deliberately choosing wrong.

This sign is great, but it isn’t in Saint Paul.

This sign isn’t in Saint Paul. It’s courtesy of the Saint Anthony District Council.

This isn’t in Saint Paul either.

The USAF: home of the need…the need, for speed! But you have to drive 25, except in residential areas, where the limit is 15, because the USAF is a data-driven organization, and the Wing Commander doesn’t care how fast you want to drive.

  • Reduce – or eliminate – signals and signs.

The purpose of most electronic traffic controls, and many signs, is to facilitate the (relatively) rapid and smooth flow of motor vehicles. Pedestrian and cyclist safety is a tertiary concern. In October 2015, the Yorkshire town of Beverly, England, suffered a failure of 42 electronic traffic signals…and found that traffic suddenly flowed more smoothly. Cities in England are now experimenting with removing lines from streets, finding that it induces uncertainty and reduces speeds by 13%. In fact, electronic traffic signals are where nearly half of the crashes in a city occur, because all eyes involved are on the signal, rather than on the other vehicles, or the cyclists and pedestrians who share the roads.

This idea, the concept of “shared spaces” or “naked streets”, is almost a form of anti-engineering; a kind of de-marking developed by the late Dutch traffic engineer Hans Monderman. His approach is more psychological than anything else, predicated on the notion that lines and signs provide a false sense of security, and even encourage drivers to only partially attend to their environment, since the signs are telling them what to do. Light turns green? Go. Sign says 45 mph? Drive 45 mph. Monderman’s idea was that if the directives and the false safety were to be removed, drivers would slow to the point where they are capable of looking out for their safety, and the safety of others. In other words, self-preservation will induce drivers to operate at speeds appropriate for conditions. To Monderman, most signs are not only dangerous, but an admission of failure on the part of the road designers.

The painted double-circle in Poynton’s de-signed monster intersection. Photo courtesy of The Guardian.

The removal of signs and directive lines has achieved remarkable things in some places, such as Poynton, England, where a monstrous five-way intersection was painted in an interesting double-traffic circle pattern, and all signage was removed. Following the change, average speeds dropped below the target of 20 mph, and there have been no fatalities. Multiple cities in Europe are now experimenting with the complete removal of traffic signage, and the results have been positive, and stunning. As the saying goes at some of the planning conferences: “Unsafe is safe”, a statement which highlights the counter-intuitive notion that signing, and particularly signaling, exists to allow people to operate motor vehicles beyond their actual capabilities. Eliminating signage has been demonstrated multiple times to actually make things safer, to the extent that municipalities in England are even considering removing white dividing lines on the road, having found that in many cases it causes speeds to drop by 13%. I hesitate to bring up bike lanes, since Saint Paul would likely seize an opportunity to eliminate them while ignoring the associated body of theory regarding signs, but cameras in Lancashire, England, have found that cars pass cyclists 7 inches close, and faster, when there is a bike lane than when there isn’t. The firm paintbrush of guidance gives people false confidence in their capabilities.

In Saint Paul, the best traffic planning is often accidental. Recently the electronic signal at Randolph and Cretin was out, temporarily replaced by a four-way stop. The result? Drivers no longer “right filtered” past cars attempting left turns on green, a common Saint Paul behavior which converts two-lane intersections into a four-lane road, crowding cyclists and pedestrians while making the left turn exceptionally dangerous. Furthermore, no drivers were racing to beat a yellow light.

This was amazing. First this silver SUV goes. The black one across the intersection is waiting…AND THE CAR BEHIND ISN’T RIGHT-FILTERING AROUND!

Now, black SUV goes. Car behind waiting like one does at a four-way stop. Silver car on the right was at the stop first, after the previous turning vehicle.

Silver car previously on right is passing out left side of frame. Now it’s the turn for the car on the far side. Notice that the Jeep behind isn’t right filtering.

Just incredible. Everyone taking their turn, all because an electronic signal was knocked out, and a temporary four way stop put in place.

A diagram of typical traffic flow at an electronically controlled Saint Paul intersection. While cars queue to turn left at the green light, other cars impatiently step on the gas and right filter, making the situation impossible for everyone.

For the brief duration of the unplanned four-way-stop, it was the safest I had ever felt crossing that street on foot, or by bike, and the safest I ever felt making a left turn off Cretin in my vehicle. Saint Paul might consider the revolutionary approach of reducing (or eliminating) reliance on electronic signaling. Drivers will slow naturally, knowing that they will have to suddenly rely on their own limited faculties. Additionally, defunct programs like “Paint the Pavement” should be revived and re-invigorated.

  • Adopt NACTO guidelines.

If Saint Paul does not want to make the bold step towards unsigned spaces, a firm commitment to the adoption of the National Association of City Transportation Officials’ guidelines are another start. St. Paul should utilize the NACTO Urban Street Design Guide and the Urban Bikeway Design Guide as foundational documents for street planning. Additionally, “road diets” and “pop up” cycletracks should be the rule, not the exception, and are low-cost, high-impact ways to nudge existing design towards NACTO guidelines.


For decades, traffic engineers have treated vehicular traffic in the same manner as plumbing: Build it bigger, wider, faster, and engineer the intersections to maximize flow throughput. The result has been the dividing of neighborhoods and communities, isolating people/pedestrians on “safe” islands that have been severed from human scaled connections by lethal and wide roads.

Recently, even West Palm Beach in Florida – a stroad-dominated and nearly unwalkable town – realized the folly of of this approach, and started reconfiguring high-speed/high-volume roads. The result was a drop in speed that made pedestrians suddenly feel safe walking about, and a near doubling of property values. Ian Lockwood, the former transportation manager of West Palm Beach, said of the changes: “What we really need is a complete paradigm shift in traffic engineering and city planning to break away from the conventional ideas that have got us in this mess. There’s still this notion that we should build big roads everywhere because the car represents personal freedom. Well, that’s bullshit. The truth is that most people are prisoners of their cars.” This in FLORIDA, of all places. Florida. Let that sink in for a moment, Saint Paul.

This section on the Engineering aspect of Vision Zero has been lengthy, and that’s because so much Education background needs to be discussed behind the counter-intuitive (or counter-plumbing) Engineering proposals. If one wants to make the optimistic assumption that the current engineering practices and concepts in St. Paul and Minnesota are not immoral, then the present state of amorality might simply be the result of a gap in Education, which will be the subject of Part 4.

Michael Daigh

About Michael Daigh

You might have seen Michael Daigh riding his bike around the Twin Cities metro. He resides in St. Paul, but only since 2015, so his opinions don't count. Michael holds an MA in History, and is the author of the book: "John Brown in Memory and Myth". He is also a decorated fighter pilot.