With this post I decided to piggyback off of the discussion currently occurring on the Institute of Transportation Engineers (ITE) forum regarding phantom trips and the critique of the ITE Trip Generation Manual. For those of you who do not know what phantom trips are, they are trips that magically appear. The document in question is located here: http://people.ucsc.edu/~adammb/publications/Millard-Ball_2015_Phantom_Trips_preprint.pdf. The discussion has been as such: folks have either been either defending or denouncing planning models and the trips they generate, and it has been an interesting back-and-forth to nerdy bystanders like myself (and to you reading this blog). However, I think the bigger question is: why the heck are we putting so much reliance on trying to predict the exact number of cars using a roadway 20 years from now? This number could possibly be a million percent off. It does not make sense!!
I will give you an example: in my previous life as a Federal employee (keep it real Barry Obama), I was the technical resource for Florida for all traffic projections for Federal projects in the State of Florida. One constant issue I dealt with were studies that consistently said that if they add this one lane, or change this one interchange, or add a single ramp, that there would be no traffic 20 years after it was built. Wow, I never knew it was that simple. Is that all we had to do? Add a lane and there will be sunshine and rainbows for everyone? Obviously, I had to hold my tongue after each of these reports came in, but it was seriously troubling. There is absolutely no way we know this is possible. Can anyone predict the future 20 years from now, let alone 6 months? The answer is no, and these reports tried to defend these future projections down to individual car. (I have to say that the folks doing these reports are doing the best they can and are following federal regulation, but the whole process is pretty ridiculous.)
So, you may ask yourself, “Okay, so what’s the harm? Why should I care about this issue?” Well, the answer is simple: billions of dollars of tax money are being justified with seemingly willy-nilly numbers. Roads are being built/expanded/rehabbed with risky data and numbers, and your gas/sales/property taxes are used inefficiently.
The most glaring of these issues is shown with new toll roads. Numerous bonds for toll roads have been rated either just above junk bonds or at junk bonds (Austin: http://usa.streetsblog.org/2013/10/23/tifia-backed-privately-operated-texas-toll-road-flirts-with-default/, Indiana: http://usa.streetsblog.org/2014/11/18/the-indiana-toll-road-and-the-dark-side-of-privately-financed-highways/, Ohio: http://streetsblog.net/2013/11/25/toll-roads-increasingly-put-taxpayers-at-risk/). To my non-finance friends, this means that, in the eyes of the investor, your deadbeat Uncle Charlie and a toll agency have the same potential to pay back the invested capital. This is troubling, as these people are not just trying to sell you a toy (KB Toys), give you internet (AOL), or trying to give you the blue light special (Kmart): they are building roads! They are placing thousands of tons of concrete, volumes of asphalt and steel, and bulldozing the environment.
The next question you might ask is, “Well, if it ain’t broke don’t fix it. Why should I care now and not 10 years from now? Why is this issue urgent today?” Well, for the first time in our history, our fundamental assumption that traffic increases with time is wrong. In the transportation world, this is like saying that force does not equal mass times acceleration. This goes against the fundamental first rule of planning is that: if you build it, they will come. However, this is no longer the case! USDOT has owned up to this fact. Wow! The agency that lives and breathes by people buying more gas and driving more has let the cat out of the bag.
Now, not only is reduced traffic demand an issue we need to consider. In planning models and project traffic, I have yet to see a report that shows induced demand (i.e., when a roadway gets built and drivers who had originally used a different roadway switch over to the “new and improved one”), implementation of technology on transportation (e.g., the advent of Uber, automated vehicles, etc.), or any sort of futurism (e.g., what if oil prices skyrocket or drop, what if we all got jet-packs, and other crazy futurist ideas: honestly, if you have never met a futurist or heard one speak, check this out as it is pretty wild: http://www.ted.com/talks/bruce_mccall_s_faux_nostalgia?language=en)
Well, my friend, there is a light at the end of this tunnel, and it lies within another industry: finance. I found this out by studying and attempting to pass the Chartered Financial Analyst (CFA) Exam Level 1. Now, while I did not pass (trying to study for 6 months to take the hardest test that was multitudes harder than the PE or PTOE was definitely not enough time), I learned a valuable lesson: trying to predict the future is really, really hard! Financial professionals live and die on their ability, or perceived ability, to predict the future. This is how they make money. You would think that they have found a magical recipe or at least a commonly agreed upon metric to use. However, with all the financial incentives and troves of data and analysis, their predictions are more befuddled than ever, and that is okay! To them, there is never a definitive answer, only inclinations and a bet that their predictions are correct. From the limited knowledge I have, they utilize Monte Carlo simulations showing an array of possibilities.
The figures below show a simple, although slanted, comparison to what finance
However, we were not taught this concept of a realm of possibilities, with exception of maybe a probability course. Every other class told us that “X + Y =Z,” which is not how the real world works. I remember in all my classes, whether it be fluids, structures, or even transportation that there was a certain formula and I was graded on whether or not I got the answer exactly correct. Unfortunately, I got the answers mostly wrong and am surprised that they gave me a degree, but that is another story entirely (another blog post…?)
What we should have been taught is: there is no one output for a set of inputs in the planning/forecasting/simulation realm. That type of logic is asinine. Instead, “X + Y = Z, C, V, Q, and a batman symbol.” One must understand the inputs and the reason for the inputs and conclude on an array of answers. If a single answer is preferred for whatever the case (with the key word being preferred), then the transportation professional needs to be able to detail why the other 5 or so answers did not make the cut. The answer should not be: “Well, I plugged it in the equation and it came out right.” My mentor, CT (he still has a job, so I don’t want to call him out), called these people KTI’s (knob turning idiots). I like to stereotype them as something a little more politically correct: cookbook engineers. Their knowledge is gained by how they read the cookbook, not by how well they understand the intricacies of the inputs and outputs.
So, with all this said, I feel that I have offended some of you and it would be wrong of me to denounce an important part of our profession without providing some thoughts on what we should actually do. I think, first and foremost, is we need to reexamine our long-standing laws. These include:
- Increased Capacity = Less traffic
- Suburbs are growing (more on this in a later blog post, after I finish “The End of the Suburbs,” by Liam Gallagher)
- People = cars
After these traditional items are revised, this will help bring realism back. Then, we can get to the enormous challenge of bringing accountability to planning. Will this raise the cost of planning? Yes. Will the issues of change? Most likely. Our industry is on the precipice of major change, with increasing technology and decreasing senior engineers.
*I have to thank Streetsblog for most of the resources. Without their research, I would not have been able to defend some of these items
**Note: All of these issues I have been guilty of myself at some point in my career. While it may seem that I have a finger pointed at the transportation industry, I definitely have 3 more pointed back at myself.
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