Link-based Internal and Full Cost Analysis

Full cost of travel on the Twin Cities Road Network ($/veh-km)

Recent working paper:

This paper develops a link-based full cost model, which identifies the key cost components of travel, including both internal and external versions of cost, and gives a link-based cost estimate. The key cost components for travelers are categorized as time cost, emission cost, crash cost, user monetary cost, and infrastructure cost. Selecting the Minneapolis – St. Paul (Twin Cities) Metropolitan region as the study area, the estimates show that the average full cost of travel is $0.68/veh-km, in which the time and user monetary costs account for approximately 85% of the total. Except for the infrastructure cost, highways are more cost-effective than other surface roadways considering all the other cost components, as well as the internal and full costs.

Are there too many roads?

With today’s news that President Obama is coupling tax reform with a renewed call for a major infrastructure investment (following up on his fix-it-first proposal in the State of the Union Address), we should ask the Goldilocks question: is our road infrastructure too little, just right, or not enough? Of course this depends on how, there is not simply a “lump of roads”, but rather roads of particular designs, connecting particular origins and destinations, with a length, width, and depth.

This discussion is US-centric, but applies to many developed countries. Developing countries are not there yet.

Too Little:

  1. On the side of “too little” are some economists, following on the heels of David Aschauer’s work in the 1990s about the infrastructure investment shortfall. The claim is that infrastructure investments drive economic growth.
  2. There are arguments about economies of agglomeration, which infrastructure may enhance, by operating through accessibility. To the extent accessibility increases, agglomeration increases too. This is likely to be non-linear, but may be increasing or decreasing in a particular range.
  3. There is also the stimulus argument, from macro-economists looking for useful jobs projects, to employ the unemployed.
  4. Having some redundancy in the network is also valuable, as it makes the network more robust to failures (such as terrorist acts, bridge collapses, or superstorms).
  5. Stronger roads and bridges would enable buses and trucks to be more efficient by carrying more weight.

Too Much:

  1. On the side of “too much” are arguments like those in the “Strong Towns” movement who argue that we can’t afford to maintain the infrastructure we have.
  2. Also worth noting is the lack of economic development impacts of most new investments.
  3. History suggests that if demand has peaked, supply is probably also at the peak of what we can support. This was true of rail in the 1920s, at which point the mileage of rail networks (both intercity and urban) declined. This may now be true of roads, with peak travel occurring, as we see rural areas continuing to depopulate, some places considering gravelization, some urban freeways being taken down and not replaced.
  4. It is clear we under-price what we have, so naturally that leads to more consumption than if we properly priced things. It is also clear the roads sector (and some other transport sectors) are in the mature phase of development, and roads have at best diminishing returns on investment, if not zero or negative returns.
  5. It is also clear that most roads are mostly empty most of the time, and that we build many roads far wider than are needed, so wide they can be used to store cars 24 hours a day.

I would conclude, that in general, we do have too much road infrastructure.

We mostly have too much width, perhaps a bit too much length (e.g. we could reduce the rural grid from a 1 mile to a 2 mile spacing in many places), and generally not enough depth (pavement thickness).

Some of the excess width and length should be gracefully abandoned. It may not be worth demolishing, but entropy can have its course. When it is to be rebuilt, it can also be appropriately rescaled. The term road diet is sometimes used, and applies in some cases.

That does not mean that we have all the infrastructure we need. There are surely some investments that have benefits that exceed their costs.

It also doesn’t mean that all infrastructure should be abandoned. Most infrastructure is quite useful, and we have developed land conditioned on the existence of that infrastructure. So abandonment is not necessarily practical.

So in contrast with the Betteridge’s Law of Headlines that any question in an article title is answered with a “no”. Here I think the answer is generally yes.

The reallocation of roadspace

Cross-posted from The reallocation of roadspace

The (re-)allocation of roadspace

Minneapolis MapThe urban public right-of-way (roadspace) is a scarce resource that is now publicly allocated.Typically at the outside is a sidewalk (this might actually be on private property, but there is a right-of-passage there). Between the sidewalk and the street there is often a “boulevard”, a planted strip with occasional street trees and the frequent sign. There there is a curb and gutter. Next to this is the “street” on which may be on-street parking, followed by movement lanes. The on-street parking may be free or metered. In some places there are designated bike lanes, or even bus lanes. In some places the lanes are reversible in direction, in others they are one-way. There may be bus-stops. Underneath the road are public utilities (water, sewer, natural gas), above or below are cabled utilities (phone, electricity, television). There may be street-lighting. There may be wi-fi antennas on the street-lights. Some blocks are bisected by alleys, others see neighbors abut.If there is no alley, Garbage, recycling, and reuse trucks ply the roads, and the material for pickup is placed on the boulevard. Driveways may cut into the street.

People may wait on the boulevard for buses (school buses or public transit). There may be a shelter, or a sign. The buses may stop on the right-of-way to board and alight passengers.

We need to be more creative about how we allocate this space. In the US, most cities west of the Appalachians arrange the streets in a grid. This regular, monotonous, grid has many features, but one that is often not used to its fullest is the ability to differentiate.

Presently the links on the grid are largely equivalent, except that some links are collectors and distributors, and serve residential land uses, while others are arterials and serve commercial land uses, and have transit running on them.

Let’s imagine we have a significant commercial arterial every tenth east-west street (10th, 20th , 30th, and so on) (approximately every mile). How do we allocate the road space on the 9 blocks between them? Are they all the same (serving moving and stored cars), or can they be differentiated.

Suppose instead of assuming all modes should mix (and therefore give dominance to the private automobile on all blocks since it has greater number, speed and mass and will win every conflict), let’s take one of those streets (say the Nines: 9th, 19th, 29th, 39th, etc.) and say it is for bicycles only. People who live on the Nines would have to park their cars on another block or in the alley behind, or maybe some off-street parking can be found. This bicycle-only street would only stop when crossing a major north-south arterial (and a yield at transit routes) or other specialize route below (i.e. on only half the blocks they would have a 50 percent chance of having a red light, and on the remaining blocks they would have unchallenged right-of-way).

These are what are called “Class I” bikeways in the jargon, as they are exclusive for bikes. (Other routes that are not otherwise allocated would implicitly be Class III bikeways, a distinction without a difference)

Suppose we dedicate the Fives (5th, 15th, 25th, 35th, etc.) exclusively to public transit and taxis. This route would be about one-half mile from the transit-served arterials, and thus would ensure all travelers are within a one-quarter mile route from a transit service (though perhaps a longer distance to a stop). The frequency here would be fairly high, and stops would be every 2.5 blocks, so the Manhattan (network) distance for the farthest passenger would be one-half mile. This route would be exclusively for transit (and taxi) movement and stops, and transit vehicles would not have to stop except at the arterials and other transit routes, where there would be stops and transfer points anyway. The Transit service would be laid out in a near perfect grid.

Suppose we dedicate the Ones (1st, 11th, 21st, …) to truck movement. Trucks still need to move through the city, but the arterials are already congested with transit and private car traffic. Freight could use other links for access and egress to particular buildings, but use only the Ones for longer distance movements within the city. The roads would be rebuilt with much stronger pavements to withstand the greater use and abuse. Other vehicles could use the Ones, for movement but there would be no on-street parking here either.

Suppose we dedicate the Threes and Sevens to one-way (west-bound and east-bound respectively) vehicular movements. These routes would move a bit faster than the two-way links, would not have to compete with stopping vehicles as much, and would draw longer distance traffic. They would be given a green wave at a socially desirable travel speed.



We would do the same thing on north-south arterials, so that 29th Avenue (N-S) meeting 29th Street (E-W) would be a bicycle-only intersection.

Some of this is familiar to Minneapolitans: 20th is Franklin Avenue, 30th is Lake Street. The Midtown Greenway is roughly 29th St (though of course it is better since it is an exclusive right-of-way). 26th St and 28th St are a one-way pair. But we have not done this strategically or fully. We mix transit and private cars on arterials. Transit buses run on 26th and 28th, not on 25th. We certainly mix trucks with cars excessively.

I am not making a specific recommendation for specific routes, I am suggesting we systematically and multi-modally reconsider roadspace allocation in order to better facilitate the movement of multiple modes in a complex environment and develop a strategy for this. Clearly specific routes will need to be bent to fit the local landscape and built environment.

Fix It First, Expand It Second, Reward It Third: A New Strategy for America’s Highways – Brookings Institution

A Political Economy of Access: Infrastructure, Networks, Cities, and Institutions by David M. Levinson and David A. King
A Political Economy of Access: Infrastructure, Networks, Cities, and Institutions by David M. Levinson and David A. King

Fix It First, Expand It Second, Reward It Third: A New Strategy for America’s Highways – Brookings Institution by Matthew E. Kahn, Professor of Economics, UCLA Institute of the Environment and Sustainability and
David M. Levinson, RP Braun/CTS Chair in Transportation, University of Minnesota

Abstract: The roads and bridges that make up our nation’s highway infrastructure are in disrepair as a result of insufficient maintenance–a maintenance deficit that increases travel times, damages vehicles, and can lead to accidents that cause injuries or even fatalities. This deficit is in part due to a prioritization of new projects over care for existing infrastructure and contributes to a higher-cost, lower-return system of investment. This paper proposes a reorganization of our national highway infrastructure priorities to “Fix It First, Expand It Second, and Reward It Third.” First, all revenues from the existing federal gasoline tax would be devoted to repair, maintain, rehabilitate, reconstruct, and enhance existing roads and bridges on the National Highway System. Second, funding for states to build new and expand existing roads would come from a newly created Federal Highway Bank, which would require benefit-cost analysis to demonstrate the efficacy of a new build. Third, new and expanded transportation infrastructure that meets or exceeds projected benefits would receive an interest rate subsidy from a Highway Performance Fund to be financed by net revenues from the Federal Highway Bank.

Read the full discussion paper
Read the brief

Fix Old Roads, Instead of Constructing New Ones, Report Urges –

Our new Brookings report (available tomorrow) makes the Economix blog of the New York Times:
Fix Old Roads, Instead of Constructing New Ones, Report Urges –

February 24, 2011, 3:50 PM
Fix It and They Will Come
On Friday morning, the Hamilton Project will release a few new proposals for helping fiscally struggling state and local governments keep their roads, bridges and other infrastructure in decent shape. One of the proposals fits a theme I’ve been writing about recently: making government programs less wasteful.
This proposal comes from Matthew Kahn of the University of California, Los Angeles, and David Levinson of the University of Minnesota. The title summarizes it: “Fix It First, Expand It Second, Reward It Third.”
Mr. Kahn and Mr. Levinson call on the federal government to devote its current funding for highways to repair, rather than to the construction of new highways. As they note, the reverse happens all too often:

The way the federal government allocates money for transportation infrastructure investments is one reason why the United States is experiencing a maintenance shortfall and falling returns on new investment. Federal highway infrastructure spending is allocated based on a series of subjective criteria that typically do not require any stringent analysis of expected benefits versus costs. Because there is often public pressure to build new projects using scarce funds, adding capacity often comes at the expense of supporting and enhancing existing infrastructure.

We build roads we don’t need instead of fixing aging roads that we do need. The Kahn-Levinson solution would force state and local governments to spend their federal dollars on repair and to raise money from investors for new construction.
New roads would have to be able to pay for themselves — “through direct user charges and by capturing some of the increase in land values near transportation improvements” — or investors wouldn’t finance them. A newly created Federal Highway Bank would serve as an intermediary between the investors and the state and local governments.
Finally, roads that exceeded expectations — were completed ahead of schedule, for instance, or reduced traffic more than expected — would be eligible for a federal interest-rate subsidy, through the highway bank.
The idea strikes me as promising. The big question, it seems, is how Congress can be persuaded to get out of the business of shiny new roads and concentrate instead on the unglamorous repair work.
The Hamilton Project — which is a branch of the Brookings Institution and tends to be filled with once and future Democratic policy makers — will host an event on Friday to discuss its new proposals.