The decline in rural VMT is partly because rural areas are associated with so much more travel than urban areas. States that have higher shares of urbanization has lower VMT per capita than the national average. Using data from the FHWA I calculated the correlation between the percent of the population that is urban and VMT per capita at -.58, which is a fairly strong association between increased urban population and lower VMT.
Rural drivers probably drive more in total, so it would make sense that an overall drop in VMT nationwide would be driven by rural drivers. Urban drivers, I suspect, can’t really drive any more. Urban congestion is such that there simply aren’t enough hours in the day to spend any more time driving.
Any data from post recession years?
That’s 2005 and a lot has happened since then. VMT’s in generally have been down or flat, prompting lots of forecasting measures to be out of date with reality. Here locally, they effect highway congestion for the periods we are forecasting transit in 2030, with associated increased travel times and time/$$ savings to justify transit improvements.
Road expansion has to adjust their programs in a similar way.
From the PSRC, 2010 Data:
“VMT per person increased substantially during the
1980s, rising from 16.3 vehicle-miles per person in 1980 to 23.2 in 1989 due to increased
vehicle ownership and an upsurge in two-worker households. VMT per person generally
leveled off or increased minimally during the 1990s and has been declining slightly since
1999 when it peaked at 24.2 VMT per person.”
Seems like even in rural areas there is more infill, more jobs, more modern shopping centers. Go to the remoter parts of Washington and Oregon, you’ll find camping grounds — but malls a few miles away!
Connecting the obvious dots:
As people have moved (back) to cities, miles travelled has gone down. Of course, prices have gone up because we aren’t increasing supply as fast as demand. We haven’t increased supply as quickly as we could because there are artificial constraints on building like height, setbacks, and parking that limit the number of homes we can build in cities. In our region the largest global warming impact comes from driving, though this is a significant source of carbon in any area.
So the best way to decrease carbon emissions is to upzone, and to start eroding the edges of single family zoning with multifamily. A similar lesson applies to anywhere in the country, or the world.
Well….I’d be careful what conclusions you draw from that data.
If you look at the totals, urban VMT is actually about twice as high as rural VMT. And, if you calc the per capita VMT for rural and urban areas you will find that per capita VMT is lower for urban areas.
So the reduction in total VMT could be driven by a reduction in per capita urban VMT, or a larger reduction in per capita rural VMT, or simply by a shift from rural to urban living (high driving rural drivers become lower driving urban drivers).
What is needed is trend data – is total urban and rural VMT reducing? And is per capita urban and rural VMT reducing? Or is it a population shift?
Why is it important? Because if the reduction in total VMT is being accomplished by a switch to urban living, then total VMT in urban areas might be stable or even increasing. Thus certain “mega-projects” in urban areas might make sense even if total VMT is declining nationwide.
There is a migration from rural to urban areas, but that’s continuous, without a sharp change at the right time.
However, there’s another, more depressing possible reason. Rural poverty.
Rural areas are getting poorer much faster than urban areas. Rural people may simply not be able to *afford* to drive as much — even though they have no other means of transportation. Combine dropping incomes with rising gas prices, and large swaths of rural America may simply have dropped below the income level where they can afford to take joyrides. I’ve seen this happen to some people in the hinterland of my city… so I wouldn’t underestimate this depressing possibility.
Retired baby boomers.