jueves, 25 de noviembre de 2010

Confesiones de un Ingeniero (de transito) en Recuperacion - Strong Towns Blog - Strong Towns

Monday
Nov222010

Confessions of a Recovering Engineer

Monday, November 22, 2010 |

After graduating from college with a civil engineering degree, I found myself working in my home town for a local engineering firm doing mostly municipal engineering (roads, sewer pipe, water pipe, stormwater). A fair percentage of my time was spent convincing people that, when it came to their road, I knew more than they did.

And of course I should know more. First, I had a technical degree from a top university. Second, I was in a path towards getting a state license (at the time I was an Engineer in Training, the four-year "apprenticeship" required to become a fully licensed Professional Engineer), which required me to pass a pretty tough test just to get started and another, more difficult, exam to conclude. Third, I was in a profession that is one of the oldest and most respected in human history, responsible for some of the greatest achievements of mankind. Fourth - and most important - I had books and books of standards to follow.

A book of standards to an engineer is better than a bible to a priest. All you have to do is to rely on the standards. Back in college I was told a story about how, in WW II, some Jewish engineers in hiding had run thousands of tedious tests on asphalt, just to produce these graphs that we still use today. Some of our craft descends from Roman engineers who did all of this a couple of millenia ago. How could I be wrong with literally thousands of years of professional practice on my side?

And, more to the point, what business would I -- let alone a property owner on a project I was working on - have in questioning the way things were done? Of course the people who wrote the standards knew better than we did. That is why they wrote the standard.

When people would tell me that they did not want a wider street, I would tell them that they had to have it for safety reasons.

When they answered that a wider street would make people drive faster and that would be seem to be less safe, especially in front of their house where their kids were playing, I would confidently tell them that the wider road was more safe, especially when combined with the other safety enhancements the standards called for.

When people objected to those other "enhancements", like removing all of the trees near the road, I told them that for safety reasons we needed to improve the sight distances and ensure that the recovery zone was free of obstacles.

When they pointed out that the "recovery zone" was also their "yard" and that their kids played kickball and hopscotch there, I recommended that they put up a fence, so long as the fence was outside of the right-of-way.

When they objected to the cost of the wider, faster, treeless road that would turn their peaceful, front yard into the viewing area for a drag strip unless they built a concrete barricade along their front property line, I informed them that progress was sometimes expensive, but these standards have been shown to work across the state, the country and the world and I could not compromise with their safety.

In retrospect I understand that this was utter insanity. Wider, faster, treeless roads not only ruin our public places, they kill people. Taking highway standards and applying them to urban and suburban streets, and even county roads, costs us thousands of lives every year. There is no earthly reason why an engineer would ever design a fourteen foot lane for a city block, yet we do it continuously. Why?

The answer is utterly shameful: Because that is the standard.

In the engineering profession's version of defensive medicine, we can't recommend standards that are not in the manual. We can't use logic to vary from a standard that gives us 60 mph design speeds on roads with intersections every 200 feet. We can't question why two cars would need to travel at high speed in opposite directions on a city block, let alone why we would want them to. We can yield to public pressure and post a speed limit -- itself a hazard -- but we can't recommend a road section that is not in the highway manual. 

When the public and politicians tell engineers that their top priorities are safety and then cost, the engineer's brain hears something completely different. The engineer hears, "Once you set a design speed and handle the projected volume of traffic, safety is the top priority. Do what it takes to make the road safe, but do it as cheaply as you can." This is why engineers return projects with asinine "safety" features, like pedestrian bridges and tunnels that nobody will ever use, and costs that are astronomical. 

An engineer designing a street or road prioritizes the world in this way, no matter how they are instructed: 

  1. Traffic speed
  2. Traffic volume
  3. Safety
  4. Cost

The rest of the world generally would prioritize things differently, as follows: 

  1. Safety
  2. Cost
  3. Traffic volume
  4. Traffic speed

In other words, the engineer first assumes that all traffic must travel at speed. Given that speed, all roads and streets are then designed to handle a projected volume. Once those parameters are set, only then does an engineer look at mitigating for safety and, finally, how to reduce the overall cost (which at that point is nearly always ridiculously expensive).

In America, it is this thinking that has designed most of our built environment, and it is nonsensical. In many ways, it is professional malpractice. If we delivered what society asked us for, we would build our local roads and streets to be safe above all else. Only then would we consider what could be done, given our budget, to handle a higher volume of cars at greater speeds.

We go to enormous expense to save ourselves small increments of driving time. This would be delusional in and of itself if it were not also making our roads and streets much less safe. I'll again reference a 2005 article from the APA Journal showing how narrower, slower streets dramatically reduce accidents, especially fatalities.

And it is that simple observation that all of those supposedly "ignorant" property owners were trying to explain to me, the engineer with all the standards, so many years ago. When you can't let your kids play in the yard, let alone ride their bike to the store, because you know the street is dangerous, then the engineering profession is not providing society any real value. It's time to stand up and demand a change.

It's time we demand that engineers build us Strong Towns.

 

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Reader Comments (40)

Here's another TIGER grant project: $250,000 for St. Paul's Complete Streets planning process. Perhaps a step in the right direction? http://www.tcstreetsforpeople.org/node/1305

November 22, 2010 | Unregistered Commenter

Faith

I think that on-street parking is overlooked in the order of how the world prioritizes streets, at least in urban areas. That is often a much higher priority over volume/speed when creating livable streets. Of course, my argument is that 'the fundamental use of streets is to move all road users safely and efficiently-- not to store private property' -- but I think that might have been overlooked in this otherwise great post.

November 22, 2010 | Unregistered Commenter

mcas

Don't discount the value of on-street parking on the pedestrian realm in making walkers feel safer with the row of parked cars blocking them from traffic. How that space is allocated, paid for and/or subsidized is a different question, but especially in urban areas, the row of parked cars can be crucial for the pedestrian experience.

November 22, 2010 | Unregistered Commenter

Steve

Truer confessions were never written. Those engineering standards also fail to take into consideration another important fact: People do not behave like water molecules. "Traffic" is made up of drivers, who are all too human.

Engineering models used to determine "safe" speeds, vehicle load, routing, etc. which fail to adequately consider the human factor --and that would be most of them-- produce flawed standards.

November 22, 2010 | Unregistered Commenter

Tracy Davis

Sweet! Nicely done, Charlie! You couldn't have said it better.

Are you going to describe sometime what and how you changed your perspective?

November 22, 2010 | Unregistered Commenter

Della Rucker

This is a really great post. I hope that traffic engineers all over take this to heart and start thinking beyond existing standards.

In response to Steve's comment:

...street parking on the pedestrian realm in making walkers feel safer with the row of parked cars blocking them from traffic...

The problem with relying on street parking to increase the perception of safety is that it does the opposite for actual safety. The parked cars, as Steve pointed out, "block them [pedestrians] from traffic" reducing the visibility of the pedestrians to traffic, and traffic's visibility to pedestrians. The parked cars (specifically open car doors) are also an enormous safety hazard for bicyclists, especially in poorly designed bike lanes without a buffer zone to keep cyclists clearly out of the doors' way.

A more appropriate barrier could come in the form of trees, planing boxes, or even simple plastic and/or concrete curbs.

November 22, 2010 | Unregistered Commenter

Will

And to add to that feeling of safety, add a bike lane between the pedestrian sidewalk and the parked cars, and you've got a winner. Although, I suppose if the streets were formulated with pedestrians in mind, they might preclude the need for bike lanes by being slower and safer to begin with.

November 22, 2010 | Unregistered Commenter

Tyler Doornbos

ASCE has been talking about these issues for years and engineers in our region have produced some exceptional developments. Professional development is important. As a licensed engineer, I took an oath to protect public safety. That is the primary objective for nearly every engineer I know.

November 22, 2010 | Unregistered Commenter

David Cowell

Sadly the author learned his traffic engineering from people who stayed in the 1950's. As someone coming into the profession in the mid-1990's I learned it as 1) who is traveling? 2) how do you keep them safe? 3) how many can travel? and 4) what will it cost? The who part was important -- it was people whether in cars, on bicycles, in a bus or walking themselves. If you look at the professional publications in traffic engineering and transportation planning from the Institute of Transportaiton engineers, they are all from the more progressive side of the profession -- see the Walkable Urban Thoroughfares book for example --- and have been for at least a decade. The author should get out more and take some professional development classes.

November 22, 2010 | Unregistered Commenter

Contrarian

It takes a lot of education to overcome the intuitive understanding that the private auto is not now, nor has it ever been, a good idea.

November 22, 2010 | Unregistered Commenter

free transit

One thing that is sadly lacking in this discussion is any mention of aesthetics. Too many recent urban streetscape designs are hideously ugly, particularly when they rely on a confusing jumble of different traffic calming strategies. Confusingly designed streets are not only ugly, they can be unsafe, because they force drivers and other street users to focus on negotiating the maze rather than watching out for pedestrians, cyclists, and other drivers. An ugly environment undeserving of care also encourages a careless attitude among drivers. Where a modest additional effort can yield a more beautiful environment it should be taken into consideration. Fortunately a clear, simple design is almost always an attractive one. It's the expensive, over-engineered solutions that tend to be the most offensive to the eye.

November 22, 2010 | Unregistered Commenter

jimble

Why isn't every residential street designed as a woonerf?
5 mph design speed until you get to the collector
(One objection might come from the fire department, unfortunately)

November 22, 2010 | Unregistered Commenter

mm

How about having to use a 22 year old transportation plan now, just because it is the plan. No need to update it, the engineers have to build it the way the plan calls for just because the plan is in place. And then when we add the standards they have for road building you get these destructive ribbons of asphalt through residential neighborhoods just because the plan called for it 22 years ago. Situation changed--so what, we have a plan. Consequences be dammed--we have a plan. Is common sense taught in engineering school?

November 22, 2010 | Unregistered Commenter

fran bates

Great article Charles.

"If we delivered what society asked us for, we would build our local roads and streets to be safe above all else."

Unfortunately, as long as government remains in control of the roads, this will never happen.

November 22, 2010 | Unregistered Commenter

Patchwick

@Contrarian: What Mr. Marohn describes is exactly the situation with my state department of transportation (NDOT - Nevada). They are living, and designing, in the 1950's, today as we write. Some of the engineers were trained in the 1950's, and if they've taken any professional development, it hasn't sunk in, and some were trained later but have been indoctrinated into the old ways. The local transportation agencies are much more enlightened, but unfortunately have to spend a lot of their energy fighting to improve the design of state projects, and spending large sums of money undoing the damage of past projects when the state dumps these projects onto the local entity.

November 23, 2010 | Unregistered Commenter

Dan Allison

Regarding this quote:

"The rest of the world generally would prioritize things differently, as follows:

1. Safety
2. Cost
3. Traffic volume
4. Traffic speed"

....

I would argue that the "rest of the world" is usually only the people who live near the project, and not the community at large. In other words, I want people to travel at 10 MPH down my street, but I want to travel as fast as possible through other people's neighborhoods. Because there are always more people who don't live on my street than do, I always lose the vote. This reverse NIMBYism may create the political mechanism that facilitates faster streets.

November 23, 2010 | Unregistered Commenter

Brent

Adding a bike lane to a street is merely adding a shoulder with a name. The purpose of shoulders is to support higher speed traffic! A higher order of road is created. Further, by removing bicyclists from the normal travel lane where they would induce caution in motorists, motorists are then enabled to to go faster. It's a double whammy of improving motoring convenience.

November 23, 2010 | Unregistered Commenter

Wayne Pein

+1 Wayne!

@Will: Bike lanes between parked cars and the curb sound like a nice idea, but have the following serious problems for practical bicycle transportation: (1) They don't allow the bicyclist to leave the bike lane for normal reasons like making a left turn and avoiding debris. (2) Debris will inevitably accumulate because bike lanes lack the sweeping action of moving cars that helps to keep the general travel lane clean. (3) Passengers have to open their doors too, and even if there is no passenger, the driver has to walk across the bike lane to get between his car and the sidewalk. (4) No city has ever been successful in enforcing non-bicyclists from using a separated bike lane: rollerbladers, skateboarders, people walking dogs, people pushing strollers, and any other pedestrian, as well as usage for storage of trash cans, piles of lawn waste, and the like. (5) Similar to the pedestrian crossing issue, the parked cars obstruct the view of the motorists in the travel lane and the bicyclists from each other, making intersections much less safe when the bicyclist suddenly pops out from behind the parked cars.

This type of "protected bike lane" is really neither protected (except from moving cars) nor a bike lane (because it prohibits usual bike lane movements). It's really more like a separated path, and those are proven to be dangerous in an urban environment along a road with lots of intersections.

November 23, 2010 | Unregistered Commenter

John Brooking

It's all about liability. If engineers don't design to established standards, they lose expensive lawsuits.

November 23, 2010 | Unregistered Commenter

Transpo

@John Brooking:
I do think that you raise some very good points, and I agree that a protected bike lane/cycle track is not the best option in all circumstances. However, it's a great option for urban environments, and all of your concerns can easily be addressed.
1) Cyclists can turn left very easily. At intersections where they want to turn they proceed to the far side of the intersection and stop at the opposing corner, wait for the light to change, and proceed along with the perpendicular traffic. This is a very tried and true method, having been in place for decades in many cities with cycle tracks.
2) Debris accumulation is not inevitable. I don't see it building up on sidewalks, so what's different about cycle tracks? Any sort of physical barrier between the car lanes and the cycle track would block road debris - even a simple curb of a few inches.
3) You are correct that passengers need to open their doors, which is why a buffer zone of a few feet between the parked car and the cycle track is in place in the best designed installations. This is similar to how parking spaces are often a bit wider than a car, leaving the driver room to step out of the car. Passengers then just need to look for bikes and walk across the cycle track - this is similar to how they would look for pedestrians on a side walk instead of charging immediately into a building.
4) You're simply incorrect. While cities with new cycle tracks have some challenges initially enforcing cycle-only use of cycle tracks, there are many, many cities with cycle tracks that do just fine. Once the community understands the purpose of the tracks the enforcement is much easier. Arguing that cycle tracks shouldn't be installed because they'd be incorrectly used initially by other road users is like arguing that we shouldn't install car lanes because pedestrians will illegally jay-walk.
5) You are correct here - the separated cycle track, especially if it's buffered by a row of cars, does reduce the visibility of the cyclist. However, with a separated lane you can install signals for bicycles that allow them just a few short moments (even as brief as a second) of a head start before cars (especially those turning across the track) begin to travel. This puts the cyclist in the motorist's field of view and greatly reduces interactions between the two. This method has been employed successfully in a great number of cities with these tracks.

The goal is really to make safer roads - not favor bikes over cars or the other way around. Instead of sticking to the textbook in every case regardless of the type of road, surrounding environment, and mode share engineers should be looking to real-world examples where injuries to all road users are reduced. The installation of a cycle tracks has in many, many cases has accomplished this goal as well as facilitated more efficient travel for pedestrians, bikes, and cars.

November 23, 2010 | Unregistered Commenter

Will

Como un ingeniero de transito se percato de que todo su quehacer pasado fue causa de muchos mas males que bienes.
Ayer en junta con Gerardo Jacome, varios asistentes se ufanaban de la omnisapiencia e infalibilidad de los ingenieros de transito en la ciudad de Mexico, y era la unica razon que aducian para aceptar sin estudios de soporte y sin cuestionar lo acertado o erroneo de la solucion planteada en el proyecto de Gabriela Cuevas.

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