How to Stop Highway Expansion (And Why)

(With Special Attention to Modeling and Wildlife)

Michael J. Vandeman, Ph.D.

Roads are one of the linchpins of environmental destruction. What are the myths used to promote their expansion, and how can they be countered? I plan to speak extemporaneously on these issues and those described in the following materials.

The First International Conference for Auto-Free Cities

May 3, 1991

The Age of the Automobile is over. The atomic bomb became obsolete the day it was dropped on Japan. The automobile (and its accoutrements, the highway and the parking lot) has just taken a bit longer to become obsolete.

The stratospheric ozone that allows life to exist on the earth (by protecting it from ultraviolet radiation) has already been reduced 4-5% over North America, causing an epidemic of skin cancer in California. About 75% of the oxygen we breathe comes from marine algae which can be killed by ultraviolet radiation. In the U.S., the biggest threat to the ozone layer is automobile air conditioners.

The automobile, in the U.S., is also the biggest contributor to global warming (or as some prefer to say, the coming ice age!). According to the U.N., we need to reduce fossil fuel consumption 50% in order to avoid the effects of global warming. Clearly, we won't need any more road space, and most likely can do with a lot less than we have. Global warming threatens thousands of species that cannot adapt or migrate fast enough.

Roads are a major factor in the destruction and fragmentation of wildlife habitat. Not only are thousands of animals killed on our roads, but many will not cross a road even if they are physically capable of doing so. The result is a loss of biodiversity and, quite often, extinction. Just as we need to travel, wildlife need migration corridors. Instead of a new round of superhighway construction, we should use gas tax funds to restore continuous wildlife corridors from border to border. Rather than bisecting essential wildlife habitats, roads should tunnel under them. (I don't think this conference is about auto-free cities; I think it is about the survival of life on the earth!)

Do you remember what fresh foods taste like? We are paving over and degrading our farmland, so that we have to bring food in from far away, even from foreign countries. Even if we can get it, it may be contaminated due to the proximity to highways. We need to eat low on the food chain, but we also need to eat low on the transportation chain!

According to the EPA, 75% of water pollution is due to runoff. A great deal of that is from roads.

Oil is due to run out in the U.S. in 30 years, and in 40-50 years worldwide. I would rather save it for making toothbrushes.

As our motor vehicle-dependent economy falls farther and farther behind, nations (like Japan, France, and Germany) that have invested in energy-efficient rail transportation have leaped ahead.

And, of course, there is air pollution. Although all scientific research on the subject shows that expanding highways increases air pollution and fuel consumption, the highway lobby continues to propagate their old myth that the way to clean up the air and save fuel is to speed up traffic by expanding highways. In the San Francisco Bay Area, federal judge Thelton Henderson recently gave our transportation planning agency the green light to continue expanding all of our highways. All they have to do is run the projects through a phony computer model that "proves" the projects will improve air quality.

What Can We Do About It?

Most people's approach is to (a) blame someone else, and then (b) try to get that other person to change. This ignores a basic fact of life: the only behavior you can control is your own. However, this is quite sufficient. If everyone decided to stop buying cars and gasoline, there would have been no war in the Middle East. Our air pollution problems would be minor. Nobody could seriously suggest that we need more freeways. The oil and automobile companies could ensure their future by converting to businesses compatible with an environmentally sustainable society.

There are a few who are profiting from the status quo, whom no amount of information will penetrate. But from what I have seen, most people, given the right information, will do the right thing. We need to make sure that information about the environmental effects of the automobile and of highway construction is spread worldwide, as rapidly as possible. The "media" are mostly owned or controlled by those who want to preserve the status quo, so we are left with personal communication, the mail, the xerox machine, and computer networks. Everywhere I go, I look up the local environmentalists and exchange names, addresses (computer and otherwise), phone numbers, and information about the effects of highway expansion. If people don't listen well enough at home, go abroad!

We have been gloating over the fact that eastern Europe has been moving toward democracy, but we don't have democracy! We can vote for someone, but once they are in office, we lose control over them, and they are "bought" by big business. Unlike some countries, we have the ability to say how we feel about a project, and then get ignored. The highway department has to describe all the negative environmental effects of its projects, but then it can go ahead and build them anyway. However, nobody can force us to buy something we don't want! We need to boycott the oil and automobile companies.

The environmental problems we face cannot be solved by one person, one organization, one government agency, one company, or one country. They are so huge that they can only be solved by everybody doing their part. My part is to not own a car, to invest in and purchase from companies that protect the environment, to learn everything I can about the environmental effects of highway construction, and to spread this information all over the world. What is your part?

March 10, 1991


I am campaigning to stop all road construction around the world. Everyone is aware of the environmental costs of oil drilling, rainforest burning, and the automobile, but few people, even among environmentalists, have given much thought to the destructive power of road, highway, and freeway construction. Roads are taken for granted. Most people have allowed themselves to become so dependent on the automobile that the destruction caused by cars and roads has become invisible to them.

Roads are at the crux of almost every current environmental problem, and hence, halting the expansion of the highway system (and other parts of our auto-dependent culture) is one of the most effective spigots by which we can choke off environmental destruction.

The automobile (due to auto air conditioners) is the greatest threat in the U.S. to the ozone layer that protects all life on the Earth. It is also the largest U.S. contributor to global warming. Highways kill wildlife (including many endangered and threatened species) in huge numbers, both directly on the road and through habitat fragmentation and degradation. They are a big factor in the loss of biodiversity and its consequent extinctions. Highway expansion -- and the urban sprawl that it feeds -- destroys precious farmland and open spaces. It increases per capita energy consumption and pollutant emission. And, of course, it kills and maims thousands of us, too, every year (my own mom died in a highway accident in 1951). I have never heard this mentioned, but it is obvious that sprawl begets more sprawl, because people who grow up in an auto-dependent environment acquire the values that perpetuate it (have you ever heard of "cognitive dissonance"? -- people who invest a lot in something have a tendency to defend it).

It is impossible to drill for oil, log, or even deluge the wilderness with tourists without roads. Roads are key. And, of course, while diverting funds away from road construction, we can make them available to promote (in order of priority) walking, bicycling, rail, and buses (or even to pay off the national debt or house the homeless -- equally worthy causes).

Please accept the enclosed information and help me spread it as far and widely as possible. If you are fighting against road construction in your area, please let me know if I can help you in any way. In the San Francisco Bay Area, I and my friends have managed to bring all freeway construction to a halt (at least temporarily) via a lawsuit under the federal Clean Air Act. If you have information about the environmental effects of highway expansion, I would appreciate it very much if you could send me a copy of it.

Snake Oil in a Computer --

The Pseudo-Science of Transportation Modeling

Michael J. Vandeman

August 16, 1991

This is the Decade of the Environment. Planners, politicians, and other decision-makers want to know what effect their projects will have on the environment. In many cases they don't really want to know, but want to convince their constituents that the results will be beneficial, or at least neutral. In both cases, computer modeling is being used to "answer" the questions. But does computer modeling answer the questions?

If you buy a ballpoint pen, you can quickly determine if it does what it is advertised to do. The pen either writes well enough, or it doesn't. If you buy a medicine, it becomes more difficult. Perhaps the improvement in your illness is a placebo effect. Maybe there is an effective ingredient, but you are also paying for several "fillers". Maybe you get worse before you get better. Maybe the body cures itself and the drug is irrelevant. "Snake oil" is any medicine that has not been proven effective. Computer modeling of transportation projects (e.g. air quality impacts) is, precisely speaking, snake oil.

First a word about my qualifications: I have a B.A. Magna cum Laude from the University of California at Berkeley in Mathematics, With Special Distinction in Mathematics. As a Junior at U.C. Berkeley, I ranked 37 1/2th out of 1300 college math students in the nation in the annual mathematics contest sponsored by the Mathematical Association of America. I have an M.A. in Mathematics (including study in Statistics) from Harvard University. And my Ph.D. from the University of California at Los Angeles is in Psychology, concentrating in Psychometrics. Psychometrics is the science of the measurement of human behavior and traits, and forms the scientific basis upon which transportation modeling and all other forms of human measurement rest. I taught measurement theory -- specifically, Reliability and Validity -- at California State University, San Francisco. I have been a computer programmer for 29 years. I taught computer science for U.C. Berkeley Extension. In other words, I am an expert in mathematics, statistics, scientific method, measurement science (including modeling), and computer science.

Modeling is really a very simple process, when the modeler is not trying to make it mysterious. A scientific principle is expressed in the form of a mathematical formula. Then data are substituted for the variables in the formula, allowing a result to be computed (e.g. emissions of CO, from vehicle type, speed, temperature, etc.). When the formula is in dispute, statistics must be used to determine if it does what its users want it to do. The relevant factors are reliability (giving repeatable results) and validity (measuring what it is supposed to be measuring). Both are measured using correlations, and only qualify the model to be utilized in situations similar to those in which it was validated, if at all. For example, an intelligence test that was validated only on white, middle class Americans could be expected to give meaningful results only when used with such subjects.

If every measure must be validated by comparing it with "the real thing", one might ask why measures and models are used at all -- why not just use the "real thing"? The answer is simply practicality: the test is relatively quick and easy to administer, whereas rigorous scientific research is very slow and expensive. A yardstick is available in any hardware store, but a highly accurate scientific instrument is unwieldy and extremely expensive. However, one must never forget that the reliability and validity of the measure or model is strictly limited; a judgment of reliability and validity doesn't confer any magical ability to predict accurately in all situations, nor any special consonance of the formula used with the forces that guide the universe!

Even in physics, the "hardest" of the sciences, reliability and validity are limited. Newtonian physics may be adequate to predict events on Earth, but fails utterly when applied to the behavior of the stars or the nucleus of the atom. There, the more accurate formulas of Einstein's Relativity must be used. When we come to predicting human behavior, both reliability and validity tend to be so low that accurate predictions are impossible. In other words, the probability that your conclusion is correct would be very close to 0.5. It could not be relied upon. And where the stakes are as high as they are with highway construction (air pollution and massive environmental destruction on one hand, loss of millions of dollars of federal and state subsidies on the other), transportation models are far too unreliable a tool.

Take, as an example, a bathroom scale. It is "calibrated" by turning a thumbscrew until it reads zero when no weight is on it. This only guarantees an accurate reading at one point -- zero. It does not guarantee that any other reading of the scale is correct. Bathroom scales are generally fairly "reliable". In other words, if you weigh yourself several times, and if others weigh you using that scale, the readings will all be very close, if not identical (assuming, of course, that you don't snack or go to the bathroom in between weighings!). The scale is also fairly "valid": the readings are close to those that our most accurate scientific scales would give. This is because the internal mechanism of the scale responds in a fairly linear fashion to weight, and because the dial has been designed ("calibrated") in such a way that a 100 pound weight causes it to read "100". However, it is not perfect. Jumping up and down on it might affect its future accuracy, as might metal fatigue. It is also important to use the tool properly: it is not designed to accurately weigh either bacteria or sumo wrestlers: it is reliable and valid only within a certain range of uses.

It is extremely important that the reliability and validity of the instrument actually be measured, within its intended domain of use (e.g., in this case, with humans between, say, 50 and 250 pounds), and that the results be publicly available: without these two numbers (usually given in terms of a "correlation coefficient"), the manufacturer has no right to advertise and sell the scale as a measuring instrument! (Some manufacturers circumvent such requirements by advertising their device as a toy, conversation piece, decoration, etc., instead of a measuring instrument.) In commercial use, such instruments must pass strict regulations. For example, a grocer can be jailed for deliberately using an inaccurate scale for weighing his goods.

In the case of instruments that purport to predict the future, similar criteria obtain: their results must be reliable (achieve very similar results when repeated by the same or different measurers) and valid (correlate highly with "reality" -- that is, with actual values of the variables that are being predicted). For example, independent parties should be able to obtain highly correlated (close) values when using a model to predict future pollutant emissions from a highway project, and these predictions must correlate highly with actual emissions in test (validation) situations. In addition, a model developed and validated in Los Angeles might not be valid for use in another part of the country, such as Berkeley (due, perhaps, to different attitudes toward the automobile?).

MTC (the Metropolitan Transportation Commission, of the San Francisco Bay Area) and its consultants violate all of the rules of measurement science in attempting to predict emissions changes due to highway expansion. The documentation for both MTCFCAST and STEP (MTC's computer models for predicting the impacts of transportation projects) reveals no evidence that reliability was ever measured. It makes vague, non-quantified claims of validity, but shows no evidence that the concept of validity was even understood. After running the model, the results were compared with one set of data. Then in a process they called "calibration", they modified the coefficients of the formula to make the model conform to that set of data. They imply that this process makes the model valid. Actually, all that it does is to make the formula "predict" one set of data. If it were to be applied to another set of data, or if a different factor were to be "predicted" using it, even if it were applied to a similar set of data, there is absolutely no guarantee that it would continue to predict accurately. In other words, this process does not result in a valid model. It merely conforms the data to the model. As an analogy, it is as if MTC had a ruler made of putty, and stretched or shrank it in different situations to make it register in a way convenient to the situation. If the formula is wrong, changing its coefficients won't help. An entirely different formula may be required!

All of the models use a standard formula that they call a "logit model equation". An example is P(q,i-j) = exp(Uj) / SUM(exp(Uk)) (k=1 to j). Here "exp" means e raised to a certain power, where e is the base of the natural logarithms. Out of the billions of possible formulas that could be used in the model, there is absolutely nothing special about this one, that qualifies it to be used in transportation modeling! The probability that it is the best formula to use is practically zero. The fact that it has been used by others has nothing whatever to do with whether it is valid.

In short, it is extremely unlikely that MTC's models have sufficient validity even to predict in situations similar to ones used in the past. And even if they had some reliability and validity in such situations, the probability that the models would continue to work in new situations (e.g. the collapse of a segment of a freeway, or the expansion of a freeway not studied before) is vanishingly small. Stated more simply, "Garbage In -- Garbage Out" (GIGO). Saying that they are "state of the art" with regard to transportation and air quality modeling merely compares garbage with garbage. Transportation modelers are not known for their impartiality, nor for their sophistication with regard to statistics or measurement science.

So how, then, are we to predict the effects of freeway expansion, if all current models are worthless? We have to fall back on basic scientific research, which is not easy or cheap, but which is the only way we have of reliably answering such questions. Agencies or researchers that receive funding for supporting the building of freeways have little motivation to develop accurate models, when they have models that give them the conclusions that they wish (basically, an extension of the status quo). They have even less interest in funding or conducting honest, unbiased research on this question. It can only be accomplished by scientists who have not been "bought" by highway interests.

On the other hand, why do any research? Isn't it obvious that expanding highways can only encourage prople to drive more, and hence worsen air quality?! And if, as required by the greenhouse effect, we must decrease traffic by 50% below current levels, isn't it obvious that we won't need all that extra pavement?!

Common sense leads one to ignore lies told by computers, just as we learned in the past to ignore the lies told by statistics, politicians, and snake oil salesmen.

Unfortunately, some decision makers still take these models seriously, and some of their constituents are taken in by them. The Bay Area Air Quality Management District, in the Draft Environmental Impact Report for its proposed State Clean Air Plan, called the MTC modeling process "beyond state of the art"! U.S. District Court (Ninth Circuit) judge Thelton Henderson rebuked MTC for its earlier air quality conformity (with the federal Clean Air Act) assessment procedure for highway projects, where they simply rated them as "Beneficial", "Neutral", or "Potentially Detrimental", and put all highway expansion in the Bay Area on hold with an injunction. However, he accepted their new procedures -- apparently because they used a computer and some formulas in common use among planners -- in spite of the fact that the models have never been validated! In other words, Judge Henderson has nullified the conformity assessment requirements of the Clean Air Act: if you want to build a new freeway, all you have to do is run some numbers through a computer model that "proves" it will improve air quality. If the computer says highway expansion is good for the air, then, by golly, it must be true!

Because this was a federal suit (Sierra Club vs. MTC), Henderson's decision has set a precedent for the whole United States. MTC's consultant, Greig Harvey, is now in great demand around the country, where other pro-highway planners and agencies will have to use similar procedures to prove that their highway projects will help clean up the air. For those of us who don't want to see our neighborhoods and the rest of the world turned into another Los Angeles, it behooves us to arm ourselves with some knowledge of mathematics, computer programming, and measurement science. Learn to recognize snake oil! And let's use our freedom of speech to demand honesty (and clean air) from our government.

May 21, 1991

Richard Tolmach, President

Modern Transit Society

P.O. Box 981

Sacramento, California 95812

Re: May-June, 1991 "Moving People"

Dear Richard:

I just finished reading the May-June issue of "Moving People". I loved it! This is exactly the informative, hard-hitting, no-punches-pulled kind of journalism that caused me to join the Modern Transit Society (and the California Transit League) in the first place. The highway lobby has never bothered to "fight fair"; why should we be burdened with decorum? Truth is our currency, and is the only one that has any value.

I especially appreciated R.D. Jones's letter regarding hypocritical environmentalists. Can you please send me his/her phone number or address, or send him/her a copy of this letter?

A few heretical thoughts: In answer to Mr/Ms Whitsell, who wants separate bike lanes: construction is expensive. And besides, bike lanes won't be necessary when we get enough cars off the road. I almost never have to ride with auto traffic, because I use residential streets where such traffic is almost nonexistent. And when I have to ride with cars, I have perfected some wobbling movements that tell approaching cars that "this guy is out of control and not to be trusted"! It is amazing how they slow down. (Of course, at the last minute, I wobble back over to the right.) Besides, oil in the U.S. is expected to run out in 30 years, and we will have far fewer cars to worry about; then we will have all roads for bike lanes!

Akos's article on the destruction of rail transit was great, but it didn't go far enough. At this very moment, we are repeating the very same process! We are destroying our farms and paving over our most valuable farmland in the same way that we destroyed our rail transit systems! One of these days, we are going to wake up and notice that all of our food is being shipped in from hundreds or thousands of miles away. Or it is contaminated with lead or other toxics due to the proximity of the farm to a freeway. And we will suddenly realize why our health has been gradually deteriorating. The yoghurt I eat every day for breakfast is labelled "Eugene, Oregon". (Of course, it didn't necessarily come from there.) All items for sale should be labelled with where they came from, how they were transported, and how they should be recycled.

And in like fashion, we are blindly driving most of the wildlife endemic to the U.S. to extinction. Roads (and, to a lesser degree, rail lines) divide and fragment habitats, causing a loss of biodiversity (animals often are psychologically unable to cross roads, even if they are physically capable). Or the animals are directly killed by high-speed traffic. The only way to halt this tragedy is to create continuous wildlife corridors from border to border, east-west and north-south. Roads, and possibly rail lines, should tunnel under the corridors, and they should be largely off-limits to human beings. We need to take our heads out of the sand and notice that we share the Earth with other forms of life.

Thursday I went to a hearing at the Air Resources Board on whether expanding highways (in the form of HOV lanes) is a valid air quality improvement measure. Out of the whole state of California, only 2 people besides myself showed up to testify -- Katharine Thompson (whom I notified of the meeting), and Prof. Bob Johnston of U.C. Davis. How are we going to get more people with the time and energy to work on protecting the community? Car ownership and child-rearing are two activities that come to mind that cause people to have little time to devote to improving and protecting the community. It would be clearly impossible for me to do the reading and information-spreading that I do if I had to spend time driving, taking care of a car, or taking care of a child (and, of course, human population growth is one of our major problems). Mr/Ms Jones was on the right track, but didn't say it: we are all too selfish: we spend too much time feathering our own nests, while the community crumbles around us. Thank God for the people like Katharine and Bob who work to protect the rest of us!

October 19, 1991

Stephen Wheeler

Re: Bicycle Activism

Dear Stephen:

After our conversation yesterday, I tried to understand my uncomfortability with your approach to forwarding the cause of bicyclists in Berkeley. I think I have discovered the cause.

Bicycling has been around for about a hundred years, as has the automobile. In that time, bicycling has steadily lost ground, while the automobile has steadily expanded its power and sphere of influence. Let's be honest. In over a hundred years, in spite of the efforts of millions of enthusiastic activists, bicycling has made no meaningful progress whatsoever!

Why? Obviously, because we have allowed the automobile and its proponents to take over our lives, our natural resources, our land, our time, our government, and our wealth. We ourselves have fallen for the same myths that have imprisoned the whole world in a race to see who can squander the world's natural legacy the fastest. We own cars. We fill them with oil and gasoline. We drive them to our backpacking trips and to our Sierra Club meetings. We support our government in its rush to kowtow to the every whim of the auto users. We allow our tax dollars to be spent paving over our most valuable farm land, putting out car fires, dealing with traffic accidents, signalizing streets, and providing everyone with free parking. We are our own worst enemies!

As the highway lobby bulldozes aside the needs of the local community in order to rape West Oakland once again with a 20-lane freeway (no, that is not a misprint; the right-of-way is 262 feet, as shown in Exh. 12-2.6!), the mild-mannered Alex Zuckermann merely asks "that bicycle access be incorporated into the design of the proposed Cypress facility" (1/18/91 letter to Caltrans). There seems to be a bit of a reality gap here. Who with any sense would want to bicycle near a freeway?! Bicyclists, because they exercise (even near cars!), incur a much greater risk from air pollution than drivers and even walkers. They, of all people, would seem to have an interest in clean air, and hence in stopping the progress of the freeway juggernaut.

It is high time that bicyclists, transit advocates, and other pedestrians stop begging for the crumbs dropped from the table of the auto users. We have all stolen the homes and habitats of our wildlife. Wildlife have no way to defend themselves. But bicyclists don't have that excuse. We vote. We spend money on the products of the auto and oil industries. We pay the taxes that subsidize the automobile-dependent government, the auto-dependent industry, the auto-dependent landscape.

No significant progress will ever be made until bicyclists stand up on their hind legs and demand an end to their imprisonment. We can't do this while surviving on hand-me-down crumbs from those with the real power. We have to break the back of the automobile/highway system: stop voting for pro-highway politicians; stop spending our hard-earned money (what's left after the auto/highway lobby takes its cut) on auto company and oil company products; start demanding an end to the welfare system for the (rich) auto users. And in general make sure that our every movement tends in that direction, and not in the direction of more accommodating of the automobile (and the truck and other relatives of the auto). Nobody is forcing us to buy the products that finance the auto/highway lobby.

Are we slow learners? Isn't 100 years of enslavement enough? Lincoln freed the involuntary slaves in 1861. We another Lincoln to free the voluntary slaves.

November 28, 1991

The Editor

Sierra Club Yodeler

Re: The Mokelumne River, or Wilderness -- Who Owns It?

It is high time that the premier environmental organization in the world address this, the premier environmental issue. I have noticed lately at environmental and transit conferences an unspoken assumption that people own the world and that only people matter. There are talks and meetings on how to divide up the world -- among us humans -- with at best a paltry crumb of the pie for wildlife. Usually, wildlife's share is not even discussed. When it is discussed, the assumption is always made that, of course, hiking trails and other human access is to be included.

Recently, I have been suggesting that we need continuous, inviolate wildlife corridors running from border to border, north/south and east/west (with all human facilities such as roads crossing them only by tunneling underneath). One person responded, with no hesitation, that of course to make them politically palatable, they should include hiking trails! Of course that completely misses the point. Not all wildlife can tolerate close association with humans. We must also have areas that are completely off-limits to humans!

The Sierra Club should not be lobbying to open up more wilderness areas to human access (even for "responsible" uses, such as rafting), but rather the reverse: lobbying to protect wildlife (who cannot lobby or protect themselves) by closing off large, interconnecting habitats to human access and remove the roads that provide and invite human access. The Conservation Committee's vote to try open up the Mokelumne River to more human access is misguided and should be reversed!


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