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Re: SG-W:/ Transportation website

The Texas Transportation Institute (TTI) 1999 Annual Urban Mobility study
that the Tripnet analysis is based on has set off a flurry of analyses.  The
Surface Transportation Policy Project (STPP) has produced their own report
"Why Are The Roads So Congested?" that pins the blame on sprawl development.
STPP disagrees with Tripnet on whether the solution is to build more roads.

The big argument is to what extent does added capacity induce increased
usage.  Tripnet refers to a 1998 FHWA study that they say concluded that
only 5-13% of increased usage on increased capacity roadways is due to
induced trips.  Without knowing the time-frame of that study, it's hard to
know whether that figure is relevant.  Increased trips due to increased
capacity has both immediate and long-term inputs, as people change their
transportation choices and then their lifestyles to take advantage of the
increased capacity.

The STPP report refers to the TTI data as well as a 1997 FHWA study to
conclude that each 10% increase in size of the highway network (or 10%
improvement in travel time) results in a 5.3% increase in induced travel (5%
in the travel time case).  The STPP report mentions the longer term
lifestyle changes, but it isn't clear whether that's included in the
percentages they list.

The TTI report can be found at http://mobility.tamu.edu
The STPP report can be found at http://www.transact.org
Steve listed the Tripnet address below.


----- Original Message -----
From: Steve Bean <sbean@berginc.com>
Subject: SG-W:/ Transportation website

> Ken and other who might be interested,
> I've come across two interesting articles on a website called "The Road
> Information Program" (TRIP), at http://www.tripnet.org/.
> "A Balanced Approach to Relieving Traffic Congestion: An Analysis of the
> Texas Transportation Institute's Report on Regional Traffic Congestion
> Trends" comes to some interesting conclusions about the affects of road
> widening.
> "Smart Growth: A Wolf in Sheep's Clothing? (March 1999)" seems to be
> working off a number of assumptions that we would do well to expose in
> any efforts to stop sprawl.
> I haven't had time to read either one very closely, but they seem worth
> examining. The site also has pages on clean air issues and gasoline taxes.
> Steve

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