the latest press release from the autoist and highway lobby:
More jobs and cheaper gasoline come with a big, honking downside: U.S. roads are more clogged than ever now that the recession is in the rearview mirror.Over at the City Observatory, they've got a handy critique, "Questioning Congestion Costs." One of the slides has an especially damning methodological point:
Commuters in Washington, D.C., suffer the most, losing an average of 82 hours a year to rush-hour slowdowns, a new study finds. Los Angeles, San Francisco and New York come next on the list of urban areas with the longest delays.
But the pain reaches across the nation.
Overall, American motorists are stuck in traffic about 5 percent more than they were in 2007, the pre-recession peak, says the report from the Texas A&M Transportation Institute and INRIX Inc., which analyzes traffic data....
Overall, Americans experienced 6.9 billion hours of traffic delays in 2014 compared to 6.6 billion in 2007 and 1.8 billion in 1982.
The way the travel time index is used to compute “costs” is to compare what are called “free flow” speeds with the actual speed on the roadway system.Slowing in order to comply with the lawful speed limit is counted as "congestion." That's messed up, and a terrible instance of padding the results. But counting anything less than free-flow as a fault is the essence of hydraulic autoism!
The baseline assumption used by the travel time index–that any reduction in speed from free flow levels on the roadway system represents a “cost” is simply wrong. Free flow travel speeds on many roads exceed the posted speed limit, and so the travel time index methodology can compute a cost associated with the time lost to travelers who cannot exceed the speed limit. Todd Litman estimates that a significant fraction of what is labeled congestion costs is actually compliance with posted speed limits.
Somewhere between a quarter to half of estimated congestion costs represent speed compliance. In more congested cities like Los Angeles and Miami, a majority of all time losses attributed to congestion involve slowing down to the posted speed limit. [italics added]
Maybe this latest study's different, but it would be surprising. Be very wary of its claims.
|From back in June, with assist from CO2Now|
Additionally, we should also consider safety, and crashes cost far more than congestion.
|2011 AAA Crashes vs. Congestion Study|