"Martin Edwards" wrote in message
...
Martin Rich wrote:
On Sat, 10 May 2008 19:42:03 -0700, "Jack May"
wrote:

Instead they find that a very high percentage of the people are already
using transit and just switch to other transit systems when they open
because of an advantage in getting to work cheaper, faster, better than
the
transit system they were using. So building new transit systems tends
to
not decrease car traffic.

Wading into this late but still...

The statement above presupposes that the only measure of success of
public transport investment is whether it gets people to switch out of
their cars. In practice, in a place where cars account for quite a
small minority of travel (such as Inner London) investing so that
people switch from one mode of public transport to another cheaper,
faster mode, sounds a good deal, especially if it results in
alleviating congestion. As I understand it, a lot of the cost-benefit
analysis for transport investment in London, going right back to the
Victoria Line in the 1960s, recognises this, though I'm very happy to
be corrected on the specific point.

In the same way, the Midland Metro has not reduced car use,

Croydon Tramlink, as expected, has captured a lot of its passengers from
buses, but it has also achieved a worthwhile modal shift from car to tram -
this was expected particularly from New Addington, where car or bus journeys
into Croydon at peak times were very slow because of congestion, so the tram
is much quicker.

Fastrack, the segregated bus network in Dartford and Gravesend, has also,
and less expectedly, achieved a significant modal shift fromn car to bus -
possibly because of the time and cost of finding somewhere to park.

Peter