One of the books that has most led me to becoming the public transport advocate that I am, is called Asphalt Nation: how the automobile took over America and how we can take it back by Jane Holtz Kay. In essence, it’s a damning indictment of auto-dependency – but one that’s backed up by a heck of a lot of research that turns it into a compelling read.
I will pluck out a few excellent paragraphs to give a taste of what the rest of the book is like – but I do strongly recommend people interested in transport matters either buy the book or at least get a hold of it for a read.
Anyway, without further delay, here’s what Ms Kay says about induced demand:
For decades traffic experts have observed the capacity of more highways to simply breed more traffic. “If you built it, they will come,” the popular phrase, is the bleak truth confirmed by science and history. “Generated traffic” is the professional phrase used to describe the traffic generated by increased roads. “Triple convergence,” another term, describes how more road space promotes more traffic in Anthony Downs’s Stuck in Traffic; that is, if you have more road at peak hours, more cars will converge for three reasons: Some will converge for the improved roadway (spatial convergence), some for the more convenient time (temporal convergence), and some from public transportation (modal convergence). Equally glum and mathematical, the so-called Braess’s paradox confirms that “by adding capacity to a crowded highway network you could actually slow things down”. Add the experience of history, and you see why our road building prompts even some federal highway officials to predict that congestion will quadruple in the next twenty years.
One can only wish that the concept of induced demand had reached transport planning thinking in this corner of the world. We might not be considering spending $860 million to widen the northwest motorway.
And on the amount of space in our cities we dedicate to the automobile:
The numbers are comprehensible. At rest, the automobile needs three parking space in its daily rounds – one at home, one at work and one in the shopping centre. In motion, going through the ritual of to-ing and fro-ing, driving along the street, circling through the garage to read that parking space, it needs more. The space for the car’s entering, the radius for its turning, and the dimensions for us sitting idle mean that asphalt competes for space with architecture and wins.
Put more mathematically, in an office building handing out one parking spot for every employee’s automobile – that’s 150-200 square feet per car, plus aisles and access lanes – adds 300 square feet per driving employee to the actual structure. In a shopping centre the five spaces for every thousand square feet of store means fifteen hundred square feet of parking. Zoning and building codes insist on ever more space for ever more cars at home. Those one-, two-, and three-car garages define the design…
…On the larger scale, city by city, suburb by suburb, we have a hard-topped nation. From 30 to 50 percent of urban America is given over to the car, two-thirds in Los Angeles. In Houston the figure for the amount of asphalt is 30 car spaces per resident. The more distant suburbs are tougher to access but worse. On the outskirts, mall lots, defined by the needs at the most jam-packed periods of shopping at Thanksgiving and Christmas, stand empty much of the year. Ironically, this means that peak time requirements hurt rather than help the surroundings and make real estate pricier.
On the environmental effects of our cars:
While Americans are in denial, we have Germany to thank for a more thoughtful accounting. In the mid-1990s, researchers at the Environment and Forecasting Institute in Heidelberg pieced together a fuller portrait of car pollution and energy consumption. To do so, they divided the automobile’s life into three stages: first, its manufacture; second, its use on the road; and third, its disposal. Probing each period, the scientists diagrammed the car’s typical ten-year life. Taking a German middle-class car and tracing 85,000 miles of traveling, they calculated the making, operating and discarding to do their assessment.
Step one in the Heidelberg study charted the manufacture of the automobile: what was consumed in its creation? The environmental toll in extracting and carrying raw materials to the factory and transforming them to make the motor vehicle was astonishing to those who had reckoned only the life after birth. Before the motor vehicle had even left the plant, the car-to-be had produced 29 tons of waste and 1,207 million cubic yards of polluted air, the researchers reported. In fact, virtually all of the waste of the one-ton vehicle had occurred. Nearly half of its lifetime emissions of dirty air had fouled the atmosphere, and the vehicle had not yet traveled a single mile.
During step two, on the road, researchers reported that the automobile pumped another 1,330 million cubic yards of polluted air into the atmosphere and scattered around 40 pounds of worn bits of road surface, tire, and brake debris on the highway. Now the dream car was ready for the automobile graveyard.
In the third and final step, when the car’s useful life was over, there was still more air polluted in dumping it. At 133 million cubic yards, plus the PCBs and huydrocarbons that accompanied the burial, the car produced another package of 66 tons of carbon dioxide and 2.7 billion cubic yards of polluted air.
The high level of environmental impact from manufacturing cars is a big contributing factor to why I don’t think electric cars are our saviour. If anything, their manufacture will use even more resources and be even more polluting than you typical car these days.
The last extract I’m going to quote relates to the financial cost of our auto-dependency, and the hidden subsidies that accompany it. While these are US figures, the situation in NZ is relatively similar as only state highways are fully funded by petrol taxes – whereas local roads are a 50/50 split between petrol taxes and local rates.
The first [part of this cost] is what we pay out of our own pocketbooks. Every year we hand out $6,000 to own and operate a two-year-old vehicle, to pay for its gas, parking, tires, depreciation, maintenance, and insurance, plus tolls for the administering, building, repairing, and operating of roads. Direct costs are visible. We open our wallets and pull out more for our car dealers, mechanics, and gas stations than for our grocers. According to the US Bureau of Labour Statistics, the average American household allots almost a fifth of its budget for the car and its related costs. With 1.77 cars per household, we’re spending 6 percent more on the car than on income tax, making the car second only to the home in the family budget and close behind our mortgage fees. That’s only the visible half.
The second, the external costs, could be more. This second sum, $3000-$5000 (but as much as $9,400 by some estimates) reflects the indirect costs of market and nonmarket expenditures. Things we rarely consider bear a dollar sign: from parking facilities to police protection, from land consumed in sprawl to registry operations, environmental damage to uncompensated accidents. These intangibles weigh us down as we pay for the car’s share of municipal and state taxes and traffic congestion. According to one estimate, exactions from US cars and trucks carry three-quarters of a trillion dollars in hidden costs each year. Nationally, that’s 35 cents a mile, in dense urban zones up to a dollar and a half…
…By hiding roadway costs in general taxes, property taxes, and sales taxes, our transportation accounting cloaks the price and promotes demand.
The whole economy suffers from the automobile’s disproportionate and unseen costs. The Automobile Club of Southern California assesses the cost of driving a relatively new car fifteen thousand miles a year in Los Angeles at the national high of $7,127. Examined closely, however, that is only a faction of the total expense. Parking given to downtown employees, for one example, is an eleven-cents-a-mile subsidy to the driver, sixteen times more than the federal gasoline tax he or she pays for the commute.
I could go on forever with good an interesting sections from the book, but I really suggest that you read the whole thing yourself.