President, ESR Research Inc.
The U.S has the largest transportation system in the
world. Astronomical references are
often used to put the enormity of the system into perspective. Thus a recent
DOT study reported that the nations 4 million miles of roads would go the
moon and back 8 times; its rail lines would circle the globe 7 times; and
that the 2.2 trillion miles traveled by cars and trucks in 2000 is nearly
one-tenth the distance to the nearest star outside our solar system.
At one time transportation was the primary means of
gathering information and communicating with people in different parts of the
country. Today most travel is undertaken as a means to an economic end. We
drive to work because we need the income. Businesses order supplies from other
states and countries because that is where they are available at least cost.
Except for pleasure trips a very small share of total travel demand - transportation is
an intermediate good. Choice of mode is based on economic considerations such
as cost, as well as speed, reliability, and convenience.
Transportation and economic efficiency are
more closely linked than ever today. In prior years manufacturers held massive
inventories in warehouses and transported goods in large consolidated batches.
Today just in time manufacturing systems require smaller, more frequent, and
precisely timed shipments. Free trade agreements linking North American and
global markets have resulted in sharp growth in cross-border and waterborne
freight shipments. These changes have raised expectations as to the speed and
reliability of transportation throughout the
The increased demands placed on the transportation
system are well documented. Goods valued
at more than 70% of total GDP are transported over the nations highways,
railroads, airlines, and port facilities. Since 1960 total ton-miles of freight
carried by all modes have nearly doubled, while ton-miles hauled by trucks have
increased by a factor of four. Passenger car travel has grown nearly three-fold
over the past four decades, to 1.6 trillion vehicle miles in 2000.
Transportation also influences land use patterns.
The Federal Highway System facilitated urban sprawl, allowing workers to live
in ever more distant suburbs while working downtown. In most metro areas radial
highway capacity did not keep pace with suburban commuter traffic. The
suburbanization of office space and jobs over past few decades is in part a response
to increased congestion on radial highways leading into city centers. These
suburban office complexes are automobile friendly, spread far apart with vast
expanses of parking lots in between. Ironically, the suburbanization of
economic activity has resulted in an increase in commuter times and distances,
albeit shifting the activity from radial movement (suburb to downtown) to
tangential movement between suburbs.
Infrastructure Demand and Supply
Despite the increased demands placed on it, the carrying
capacity of the nations transportation infrastructure has changed very little
in recent years. This is especially true
for highways, which have borne the brunt of increased freight and passenger traffic[GAH1]. Since 1980 interstate
highway lane miles have risen by 16%, while vehicle miles traveled on this roads increased 123%. Not surprisingly the economic
costs of highway congestion nationwide which include the value of time and
fuel wasted while sitting in traffic - are enormous and rising rapidly. To this
must be added the adverse impact of congestion on highway safety, air quality,
noise, and producer costs.
But highway capacity is often difficult to measure, especially over long periods of time. A commonly used capacity measure - lane miles - does not reflect changes in roadway quality, durability, or safety. Moreover, driving habits affect the capacity measure. Drivers in 2000 were moving at faster speeds with less space between vehicles than their counterparts fifteen years earlier. Effective highway capacity may therefore be expanding faster than the sluggish growth in lane miles would indicate[GAH2].
This ambiguity raises questions as to the need for additional highway infrastructure. The economic test for infrastructure investment involves computing all the benefits and costs of projects and then their rate of return. If the rate of return exceeds the costs of the funds the interest rate the investment is worthwhile. Research shows that highway infrastructure meets the cost/benefit test by a comfortable margin. At the national level, every $1 invested in highway expansion generates approximately 30 cents of cost savings annually over the life of the road improvements, implying a payback time of only four years to recoup the costs of new highway projects. This suggests that the economic benefits of investing $1 in new public highway construction are equal to, if not greater than, the benefits of investing $1 in the private sector. (See Nadiri.)
A mismatch between demand and supply is also evident
for non-highway modes. Railroads operate far fewer miles of intercity track
today than fifty years ago, but carry more ton-miles of freight. In air
transportation, the number of aircraft operated by private air carriers has
increased by more than 30% since 1990, while the number of airports serving
commercial planes has actually shrunk. The increased utilization of existing transportation
facilities, coupled with limited prospects for future expansion, raises the
specter of deterioration. So far we have avoided this. Surveys show that the
condition of our roads, bridges, and airport runways has generally improved
over the past decade even as performance, as measured by congestion and average
travel times, has worsened.
Modal Choices: Highways v. Rail v. Intermodal
Since World War II highways have supplanted
railroads as the principal inter-city transportation system for both passenger
and rail traffic. Today more than 80 percent of all passenger miles are
associated with private automobiles.
Rail transportation carries only a small percentage of total passenger
trips today, with most of those occurring in commuter rather than inter-city
rail lines.
Trucks carry the lions share of fright traffic when
measured in dollar value. Larger, more fuel efficient trucks combined with a
more extensive highway system have increased the competitiveness of trucks vis a vis rail for most products and distances. (The
distance at which rail-truck service is competitive with truck only is now
typically around 850 miles.) Trucks share of total freight traffic will increase as
E-commerce and leaner inventories put a premium on speed, flexibility, and
reliability. Trucks also benefit from a de-facto subsidy, paying far less fuel
tax relative to the wear and tear they put on highways than automobiles.
For freight transportation, however, rail and air
are still significant modes. Freight railroads carry approximately 40% of the
nations ton-miles of freight. Economic
deregulation of airlines and railroads have changed the structure of those
industries and because of enhanced competition within each industry brought
improved service and lower fares. Airlines and railroads have experienced major
consolidation through mergers and strategic alliances. Since 1980 railroads
carry 50% more freight while reducing their track by 35%, their locomotives by
32%, and their employees by 60%. These efficiencies have been passed on to
shippers through rate reductions.
Government involvement in transportation finance
also influences the choice of mode. In the
Intermodal freight shipments are growing faster than freight moved by a single mode. The era of intermodal transportation began in earnest mid-1980s when ocean carriers, railroads, and truckers teamed up to launch container service. The container revolution allows a single unit to be transferred seamlessly by truck, rail, water, or air with substantial reduction in transit time, expense, and damage, and theft. Free trade initiatives have triggered much of the rise in intermodal freight traffic, but the reverse is also true: the efficiencies made possible by intermodalism have fostered growth in international trade. (See Dempsey for a discussion of the history and benefits of containerization.)
Intermodal transport is also an integral part of the internet revolution. E-commerce and Just In Time systems train customers and businesses to order at the last minute and expect overnight delivery. In such a world fulfillment and delivery as important as product cost and quality. Overnight air-truck delivery of a single item to a single customer is reasonable given these expectations. At the same time, parties engaged in intermodal transport are using electronic interfaces to enhance connectivity and to improve the flow of information between systems. They are making increased use of innovative ITS techniques including internet based freight car ordering, car tracing, pricing, and billing.
Transportation Productivity: Doing More With Less
Despite the vast increase in passenger and freight traffic, transportation spending has declined as a percent of GDP. Freight costs have shown the most dramatic change, falling from 9% of GDP in 1960 to about 6% today. There are many reasons for this: Trucks are larger and more fuel-efficient; railroads operate with fewer workers and less equipment; Fuel costs have stabilized. Intermodal connectivity among rail, truck, and waterborne modes has increased[GAH3]. Overarching everything is the shift from a manufacturing-based economy to one based on services and information.
Two public policy decisions play a large role in the
increase in transportation productivity. First was the decision to build a
national interstate highway system. In the twenty years following passage of
the 1956 Highway Act, interstate route mileage exceeded the growth of both
trucks and passenger vehicles. When highway growth slowed in the 1970s a second
policy decision economic deregulation of trucking, airlines, and railroads
enhanced the ability of private transportation companies to utilize existing
infrastructure.
Unfortunately, the positive impacts of both
infrastructure expansion and deregulation have long since peaked. The highway model embodied in Eisenhower-era
interstate legislation effectively ended in the 1970s. Interstate highway
mileage (measured in lane miles) has increased only 16% since 1980, while
vehicle miles traveled on those roads increased 123%. Not surprisingly, the
performance of the Interstate Highway System has deteriorated. The Texas
Transportation Institute estimates that travel under severe or extremely
congested conditions doubled from 1982 to 1997 costing $72 billion in wasted
fuel and time.
Highways are increasingly viewed
not merely in traditional economic terms (as capital investment) but in terms
of how they impact air and water quality, noise, land use patterns, and other
external effects. Because of such concerns it is practically impossible to
envisage a program to greatly expand the
Nor is it likely, in the wake of the post 9/11 reductions in air passenger traffic, that airport capacity will soon be expanded. There is a renewed interest in railroads because of their advantages in terms of safety, fuel efficiency, pollution, and other environmental impacts. But the cost cutting engendered by rail deregulation has by some reports weakened the ability of many rail carriers to deliver reliable freight service[GAH4].
What Will Drive
Transportation in the
What will replace the historical
strategic drivers of transportation capacity in the
-
Intermodalism. The
- Technology. Transportation and telecommunications networks will meld, producing a fully automated highway system. Such a system will gather information on road conditions and automatically pass that information on to vehicles and other infrastructure. ITS technologies will include collision warning and avoidance device, guidance devices, electronic brakes, electronically controlled steering, and other sensors to supplement and perhaps replace human driving judgment.
- Homeland security. Just as the National Defense Highway System was the transportation systems response to the Cold War, a National Interstate Security and Logistics System may be needed now, as has been suggested in another Hudson Institute paper. This system would use GPS technology to track all components of the supply-chain: containers, chassis, rail cars, trailers, trucks, etc. Trucks and freight trains may be required to file trip plans much like aircraft file flight plans, with any deviation from plan triggering a security response. While Homeland Security is the immediate goal, the technology could support anther revolution in supply-chain logistics
- Variable-pricing policies. Demand-side strategies like time of day and distance pricing will be enabled by the new technology embedded in infrastructure and vehicles. Traditionally transportation pricing has been used to discourage travel at certain times and places. Another approach, suggested in a Hudson Institute study, would link price with a guaranteed level of service speed will always be 40mph or greater in the premium toll lanes, for example. Variable pricing regimes will help reduce dependency on motor fuel taxes.
- Financial innovations. Inflation and increased fuel economy have reduced the elasticity of motor fuel taxes relative to economic growth and highway usage. New, non-fuel tax revenues are needed to fund highway infrastructure. The trend to non-traditional finance is already well established, with states allowed to use toll road investments, private funds, publicly donated right-of-ways, and the value of ITS technology installed along highways towards its share of federal-state matching funds. New legislation allows state DOTs to help public or private entities borrow federal funds to help construct toll roads. The two forces debt leverage and public-private partnerships have yet to be fully exploited in transportation finance.
.
A Most-likely Transportation Scenario
The
Perhaps the most plausible scenario is that the nation will accommodate growing transportation demand by marginal increases in the amount spent on traditional transportation infrastructure; large increases in ITS technology; limited implementation of variable price regimes; continued moving away from the most congested locations; and by accepting increased congestion at choke points. This muddle through scenario might be tolerable, but it will leave us far from the economic optimum.
References:
Dempsey, Paul Stephen, The Law of Intermodal
Transportation: What It Was, What It Is, What It Should Be,
http://www.ie.msstate.edu/ncit/NCIT_WEB_UPDATE/Final%20Report.INTERMODAL-ARTICLE29AUG00version2.htm
Eno Transportation
Foundation, (Wilson, Rosalyn A., editor), Transportation in America 2000, with
Historical Compendium 1939-1999, 18th edition, 2001. http://www.enotrans.com/Publications/Publications_List/publications_list.html
Eno
Transportation Foundation, Report on the Fourth Forum on Intermodal Freight
Transport in
Gramlich, Edward M., Infrastructure Investment: A Review Essay, Journal of Economic Literature, Vol. XXXII, September 1994.
http://ideas.uqam.ca/ideas/data/Articles/aeajeclitv:32:y:1994:i:3:p:1176-96.html
Mudge,
Richard, Dude, Innovative Finance: Does It Have A Future, or Whats the Deal,
Man?, Hudson Institute, Working Draft, March 2003.
Nadiri, M. Ishaq, and Mamuneas,
Theofanis P., Contribution of Highway Capital to Output and Productivity
Growth in the U.S. Economy and Industries, Federal Highway Administration,
Office of Policy Development, Washington, DC,
August 1998. http://www.fhwa.dot.gov/policy/gro98cvr.htm
Transportation
Research Board, Freight Capacity for
the 21st Century, (Special Report 271), Washington, DC, September 2002. http://books.nap.edu/html/SR271/SR271.pdf
U.S.
DOT, Bureau of Transportation Statistics, Transportation in the United States:
A Review, 1997. http://ntl.bts.gov/data/titustxt.pdf
U.S.
DOT, Bureau of Transportation Statistics, Transportation Statistics Annual
Report 2000, 2001. http://www.bts.gov/publications/tsar/2000/
[GAH1]There is an interesting point to be made here. During the 1960s and 70s we were building the system with a capacity that exceeded demand. Through the 1970s, 80s and 90s demand grew while capacity remained approximately constant.
[GAH2]I guess I know why this paragraph was added but I am not sure that I agree that it should be here as a freestanding paragraph. In the overall scheme of things this is not a major effect. Freds point about we are driving faster and following closer together is true. As Don said, we used to think of 1300 vehicles per lane per hour but now we have 1500 and 1700. Perhaps in the discussion of capacity increases we could add that the driving habits have changed and increased capacity about 15%, or something like that. This sounds like a significant increase in capacity but when traffic is flowing at this point it has slowed down. There is no free space on the highway and the slightest disturbance (a police car with flashing lights sitting in the opposite direction lanes) causes the flow to hesitate and immediately a large queue of stop and go traffic forms behind the disturbance.
[GAH3]Is part of the reason the fact that service industry part of GDP has grown and does not require the physical movement of goods? Dont know if we want to add this or not.
[GAH4]This seems like a strong statement. Is it true that railroads are having difficulty providing reliable freight service?