By Randy Salzman
Although a Daily Progress editorial thinks otherwise, data from around the country is clear: When you build additional highways, you quickly create more traffic congestion.
Every highway project has different effects, but overall the data illustrates that more lanes of highway induce more people to drive more times and more places, until not only is any new roadway oversubscribed but the roadways it was intended to relieve are again backed up. A 1998 Surface Transportation Policy Project titled “If you Built it, They Will Come: Why We Can’t Build Ourselves Out of Congestion” found that 90 percent of new urban roadways in America are overwhelmed within five years.
A different analysis of 70 urban areas across 15 years concluded:
“Metro areas that invested heavily in road capacity expansion fared no better in easing congestion than metro areas that did not. Trends in congestion show that areas that exhibited greater growth in lane capacity spent roughly $22 billion more on road construction than those that didn’t, yet ended up with slightly higher congestion costs per person, wasted fuel, and travel delay… . On average the cost to relieve the congestion reported by TTI [Texas Transportation Institute] just by building roads could be thousands of dollars per family per year.
…
Unfortunately for those of us who want our tax dollars spent wisely, as both a nation and a community we’re invested in out-dated, short-term thinking. Media rarely understand or report the whole story of the American “love affair with the automobile.”
But even without the full story, all of us need to understand this: It is not population growth that creates congestion, it is new driving — which grows at an annual rate at least twice population, regardless of where the rate is measured. Since 1970, U.S. vehicle miles traveled have increased 121 percent — four times population growth.
If you think this is a chicken-and-egg problem, consider: “A 2000 study of 26 years of transportation data determined that one-third of all new road capacity in the Baltimore/Washington area has been used up by new travel that wouldn’t have occurred without highway expansion,” a 2002 report noted. “Between 64 percent and 94 percent of properties in nine Maryland highway corridors were developed after the completion of the highway — a clear demonstration of how highway construction can alter land-use patterns.”
In 2004, a study of the entire Mid-Atlantic region found “changes in lane-miles precede changes in travel” and a meta-analysis of dozens of studies found that, on average, a 10 percent increase in lane miles induces an immediate 4 percent increase in vehicle miles traveled, which climbs to 10 percent — the entire new capacity — in a few years.
Please note that these studies are all past tense. In future tense, construction advocates apply today’s driving rates to a simplistic formula and claim that “X minutes of savings per driver” will accrue due to the new highway. Although politicians and transportation boards rarely compare figures after expensive construction projects are complete, those projected time savings never exist in any post-construction analysis.
…
https://www2.dailyprogress.com/news/2010/dec/19/build-more-highways-get-more-traffic-ar-726264/oldId.2010122121254219
Biking in Baltimore