You often see claims that transit project X will reduce/alleviate/eliminate traffic congestion. E.g. This article discussing the issue
First this is usually wrong. Most transit users would not otherwise drive themselves. E.g. The 2004 Metrotransit strike could not be detected in the traffic counts. Most displaced users carpooled, walked, or biked. That is not to say there was no hardship, there was, but it was felt by transit users not drivers.
Second congestion reduction is not a good reason to support transit, anymore than claiming a new road will reduce crowding on the bus.
The purpose of transit is also not economic development, though that might occur as some people will pay a premium to live in places or work in places with good transit service. This indicates a willingness to pay above the fare being charged as well as an option value.
The purpose of transit is moving people from A to B who want (and/or don't have a good alternative) to use transit. Their willingness to pay for that trip is the primary (and perhaps dominant) benefit transit provides.
All else is noise.
- dml
Transit and road congestion
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This page contains a single entry by David Levinson published on September 17, 2011 6:06 AM.
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Many transit critics are quick to point out the impacts of the 2004 transit strike in the Twin Cities (Mpls-St.Paul). Unfortunately, they fail to look closely at the data from this interesting time period.
First Prof. Levinson says most people who bused switched to carpooling, biking or walking. True, but would that have been the case over the long haul. The strike was for 41 days-- a period of time in which many commuters could be expected to try something new (for a limited time period), but not long enough to confirm a commitment to not driving alone.
Also, more then 10% of the regional transit system did not go on strike, including all of the suburban opt-out providers which travel nearly exclusively at peak periods on typically highly congested highways. These routes not only continued to help manage congestion but picked up additional riders from routes typically served by the on-strike Metro Transit buses.
It should also be noted that half the 30,000 riders per day on the Hiawatha LRT (which the attached article discusses)did indeed leave their car to beging travelling by light rail.
Somehow, it seems that 15,000 fewer cars per day on a couple of consistently congested roads (Hiawatha Ave and 35W) would help manage congestion (note not eliminate) -- and constitute more than noise.
Play this out further, is Prof. L. suggesting that transit doesn't contribute to congestion relief in NYC or in serving Minnesota sports events or the state fair (in which 1 in 4-5 typically use transit rather than driving).
It should also be noted that half the 30,000 riders per day on the Hiawatha LRT (which the attached article discusses)did indeed leave their car to beging travelling by light rail.
That's 30,000 boardings, not 30,000 riders. Even if the 50% figure is correct (I've seen several estimates that either confirm or deny this), that would be 50% of 15,000 or 7,500 riders who are former drivers, assuming each user boards twice per day. Many of these people aren't traveling at congested times of day, as boardings on Hiawatha are spread more evenly throughout the day than a typical commuter service (e.g. Northstar). It is also a mistake to assume that all of them would be driving on congested routes (and at congested times) in the absence of Hiawatha.
Splitting hairs even further, it is hard to imagine providers that operate 10% of the transit service in the region (transit commute mode share is about 5% regionwide, so if ridership is proportional to service we are talking about 0.5 percent of regional work trips) having an impact on congestion, especially since this 10% is spread out thinly across the metro suburbs.
The lesson learned from the I-35W bridge collapse, and to an extent, from the bus strike, is that regional transportation networks are surprisingly robust. That is to say, the users of these networks are able to respond to disruptions in ways that would not be predicted by most conventional transportation models. We are left with counterfactuals that assume the worst. Somehow the Twin Cities dealt with major sporting events before Hiawatha was built (carpooling had a lot to do with it, I'm sure). New York City has managed to adapt. It has one of the best public transit networks in the country, if not the world, yet still has paralyzing congestion. That is not a coincidence.
Or to put it another way:
"You often see claims that road project X will reduce/alleviate/eliminate traffic congestion.
First this is usually wrong. Most road users would not otherwise use transit or carpool.
Second congestion reduction is not a good reason to support roads, anymore than claiming a new rail line will reduce crowding in personal automobiles.
The purpose of roads is also not economic development, though that might occur as some people will pay a premium to live in places or work in places with good road access. This indicates a willingness to pay above the fare being charged as well as an option value.
The purpose of roads is moving people from A to B who want (and/or don't have a good alternative) to use roads. Their willingness to pay for that trip is the primary (and perhaps dominant) benefit roads provide.
All else is noise."
"The purpose of transit is also not economic development"
Consider: you cannot have more people working in a central business district than can travel there every day. Buses allow more people to travel into a CBD within a given road capacity than cars. Therefore, the presence of bus service allows a CBD to have more jobs than if everyone commuted by car.
So, transit's purpose may not be economic development, but it can remove one of the constraints
You seem to be on a special screed aimed at public transit lately (see here). I'm curious about whether there was some special event or article that has led to these recent posts. I'm also curious why you don't expand these critiques to multiple forms of transportation: false claims of congestion relief and financial sustainability apply equally to road building, as many commenters have already pointed out.
@ Tom. I agree about the existence problem, that is, large cities could not exist without extensive transportation (and public transit) systems (I am after all, editor of the Journal of Transport and Land Use and have written about this). We operate at the margins of a mature system, where a marginal increase in transit has a negligible increase in economic activity. We have diminishing returns. The transit should however, like all transportation should be, self-supporting. It should be able to capture the value it provides. If it cannot charge fares or subscription services, it should get to capture value from development (e.g. by being built jointly or owning the land under high rise apartments and offices and collecting rent). But the development is not the output of transit, transportation service is the output of transit, and the tail should not (and cannot be expected to sustainably) wag the dog.
@Julie. This is not about cars vs. transit (but so many people want this to be modal warfare). The purpose of cars is moving people from A to B, and roads enable that. To fund roads on a basis other than that (economic development) is also mostly a waste, especially in a mature network. They should be evaluated on what the do or could earn.
@Mike and @Dave. There is also the induced demand problem. The congestion reduction is eaten up with new demand. That is not a bad thing or a good thing, but it is a thing which greatly diminishes the "congestion" reduction aspect of system expansions.
There is also the induced demand problem. The congestion reduction is eaten up with new demand. That is not a bad thing or a good thing, but it is a thing which greatly diminishes the "congestion" reduction aspect of system expansions.
Here's another "small L" libertarian critique. The "induced demand problem" to the extent that it exists, results from the owners (typically government) mispricing access and, by extension, capacity. It is surprising to me how often the hypothesis of induced demand is invoked without noting this. It is difficult to ascertain the demand for a good when the price is zero (or close to it).