Rail Transit Won't Reduce
September 30, 2003
Publication by the Texas Transportation
Institute (TTI) of its 2003 urban mobility report on September
30, 2003, led the transit lobby to make false claims about
the role transit can play in relieving urban congestion. The
American Public Transportation
Association claims that the report says that
"more public transportation is needed to relieve traffic
congestion". In fact, the report says no such thing.
TTI, which is part of Texas A&M's engineering program,
has published its annual urban mobility report for over a
decade, and the latest report tracks highways and driving
in each of seventy-five urban areas from 1982 through 2001.
This year, TTI added a new feature: an evaluation of how
bad congestion would be if public transit were somehow eliminated.
The Institute made the unrealistic assumption that, without
publicly supported transit, everyone who now rides transit
would start driving everywhere where they now go by transit.
Since a large share of transit users in most cities are people
who can't drive, and since privately operated transit services
would quickly replace many public transit routes, this is
Based on this assumption, TTI calculated that transit greatly
reduces urban congestion. Even this is unlikely in most urban
areas. When the main Los Angeles transit agency went on strike
for a month in 2000, few could discern any increase in congestion.
Except in a handful of major urban areas (mainly New York,
Boston, Washington, Chicago, San Francisco, and Philadelphia),
transit carries too few people to make any difference to congestion
outside of downtown areas. This makes transit really just
a subsidy to downtown densities.
Even if TTI's calculations are correct, the report says absolutely
nothing about whether further investments in transit will
reduce congestion. This is especially striking, because the
report DOES calculate that further investments in other programs
can reduce congestion:
- Freeway ramp metering currently saves motorists 73 million
hours a year, and adding it to congested freeways that do
not now have it could increase the savings by nearly 200
million more hours;
- Traffic signal coordination, which TTI calls "one
of the most cost-effective tools to increase mobility"
on signaled roads, could save motorists an added 17.2 million
hours a year;
- Incident management -- a coordinated effort to quickly
remove stalled vehicles and other highway obstructions --
could save motorists 100 million hours a year.
TTI also examined high-occupancy vehicle (HOV) lanes but
could not find evidence that they had significantly reduced
congestion in most areas. TTI said this was partly due to
a lack of data, but in fact many HOV lanes do not carry enough
multi-passenger vehicles to justify their use. TTI did not
consider the effect of turning HOV lanes into high-occupancy/toll
(HOT) lanes, as proposed by the Reason
Foundation and others.
In contrast to its statements on ramp metering, signal coordination,
and incident management, the TTI report makes no statements
about the effects of investments in transit. Or does it?
A close look at the ranking of regions over the last two
decades reveals that congestion grew fastest in those regions
that invested mainly in rail transit. By contrast, regions
that invested heavily in highways had much slower congestion
growth, even in the case of many regions that grew faster
than the rail regions.
To see this relationship, you can download the basic
TTI data in an Excel spreadsheet
summarized on the American Dream Coalition web site. You should
also download an explanation
of all the columns in the spreadsheet. This spreadsheet shows
population growth, growth of the "travel time index"
(the institute's best measure of congestion), and other pertinent
data for all seventy-five urban areas.
Although you can sort the spreadsheet in any order you wish,
it is currently sorted by the growth of the travel time index.
The travel time index is a measure of how long it takes to
get somewhere during rush hour compared to other times of
the day. If, in uncongested conditions, it takes an hour to
get somewhere, and it takes 1.5 hours in congested conditions,
then the travel time index is 1.5. If the index in 1982 was
1.1 and in 2001 it was 1.4, then the growth is .3 or, as the
institute puts it, 30 points.
The striking result is that nearly all of the ten urban areas
with the fastest congestion growth are rail cities. Two of
the areas, Seattle and Minneapolis-St. Paul, did not start
building rail lines until the end of the 1982-2001 period,
but both adapted anti-highway policies by the early 1990s.
In contrast, fast-growing communities such as Orlando and
Houston all have low rates of congestion growth, mainly because
they invested in new highways rather than rails. Las Vegas
is particularly striking. Despite being the nation's fastest
growing major urban area, new roads allowed it to have only
the seventeenth-fastest growing rate of congestion.
Las Vegas also improved its bus service by contracting out
buses to private operators, which led to a doubling of the
region's transit market share of commuters in the last decade.
No other urban area has been able to double transit's market
share in this time period, and certainly none that focused
on rail transit. About half of all rail cities, including
Baltimore, Chicago, Cleveland, Dallas-Ft. Worth, Hartford,
Philadelphia, Pittsburgh, St. Louis, and Washington, actually
had fewer transit commuters in 2000 than 1990 despite having
tens to hundreds of thousands of new commuters.
There's a good reason why rail transit doesn't work: It is
slow and inconvenient. Light-rail lines average around 20
to 25 miles per hour. Heavy-rail and commuter-rail lines are
a little faster, but when the time required to get to and
from rail stations is taken into account, rails just cannot
compete against the door-to-door convenience of autos for
must urban trips.
New rail lines often get a boost in riders over their bus
predecessors because the rail cars operate more frequently
and stop less frequently (thus going faster) than the bus
services they replace. But operating buses more frequently
with fewer stops (sometimes called "bus rapid transit")
will also boost ridership -- and cost far less.
Compared to buses or highways, rail is extremely expensive.
Light rail typically costs as much to build as a four-lane
freeway (see typical
costs). Yes, as shown in this
file (Excel spreadsheet) for
almost every operating rail line in the country, the average
American light-rail line carries as many people as just one-third
of a freeway lane. The only heavy-rail lines that carry more
people than a single freeway lane are the New York City subways.
If half of rail riders were former auto drivers--which is
optimistic--urban areas would need to build six miles of light
rail, at twenty-four times the cost, to get the same congestion
relief provided by one lane mile of freeway.
If rail transit won't reduce congestion, what will? Some
answers are provided by the TTI report, which evaluated the
effects of expanding freeway ramp metering, traffic signal
coordination, and incident management systems to all urban
Freeway ramp metering, which puts traffic signals at on ramps,
seems annoying, but it can save motorists' time by smoothing
out freeway flows. The institute says that ramp metering now
saves motorists 73 million hours per year, and this could
be quadrupled if it were implemented on more congested freeways.
Traffic signal coordination allows motorists to drive at
a steady rate of speed without stopping at each signal. The
Texas report calls it "one of the most cost-effective
tools to increase mobility" on roads that have signals.
Yet more than half the major roads that could use signal coordination
do not yet have it.
Another congestion program, called incident management, aims
to quickly remove crashed and stalled vehicles and restore
free-flowing traffic. Half of all congestion is due to such
incidents. About half of all urban areas had incident management
programs in 2001, which the Texas report says saved motorists
more than 100 million hours.
In contrast, data in the TTI report suggest that HOV lanes
haven't been very effective at reducing congestion. They don't
particularly encourage people to carpool, so they only work
when there are already enough multi-passenger vehicles for
them to succeed. However, converting HOV lanes to high-occupancy/toll
(HOT) lanes, as suggested in a Reason
Foundation report by Robert Poole and Ken Orski, could
make these lanes work much more effectively. Like HOV lanes,
HOT lanes allow high-occupancy vehicles to travel for free,
but low-occupancy vehicles could also use them provided they
paid a toll.
On one hand, the TTI report clearly showed that low-cost
programs such as ramp metering, traffic signal coordination,
and incident management can reduce congestion without building
new roads. On the other hand, the report did not evaluate
rail transit, but makes it clear that rail cities tend to
have the fastest-rising congestion. This information does
not support the rail-transit lobby's contention that diverting
more federal gas taxes from roads to transit will help reduce
In the past the Texas Transportation Institute's mobility
reports were sponsored by state departments of transportation.
This year, the American Public Transportation Association,
which represents most transit agencies as well as rail transit
engineering and construction firms, was a major co-sponsor.
The group issued its press release urging more spending on
transit within minutes of the Texas Transportation Institute's
release of its report. It is disappointing that the Institute,
which in the past has presented its data in an objective manner,
has allowed itself to become a tool of the rail-transit lobby.