Economic Merits of Road Diets and Traffic Calming

The Economic Merits of Road Diets and Traffic Calming

by Dom Nozzi

Road Diet: A modification of a road or street that narrows the road by removing travel lanes. Most commonly, a road diet involves the conversion of 4-lane street with a center turn lane to a 2-lane street with turn pockets, landscaped median, and on-street parking. The result, in general, is slower, more well-behaved car speeds with little or no reduction in traffic volume, greatly increased safety, improved street appearance, improved community pride, and a substantially improved environment for retail shops along the street.

Transportation Choice: Creating a travel environment in which it is safe, convenient, and pleasurable to use several forms of travel, such as using transit, walking or bicycling, as well as driving. The opposite of choice is an environment in which roads are hostile and distances to destinations are significant, which forces nearly all trips to be made by car.

Traffic Calming: Creating a travel environment on a street in which average motor vehicle speeds are reduced by the nature of the street design. Common calming tools include speed humps, roundabouts, traffic circles, road diets, reduced travel lane width, textured or brick street surfaces, modest turn radius size, street trees and buildings close to the street, and on-street parking.

An Economist View of Transportation Design

Many national and regional policies assume that increased driving provides economic benefits. Programs that subsidize or promote car use are often justified for the sake of economic development. Proposals that car subsidies be reduced, that roads not be widened, or transportation choice be promoted are often opposed because it is believed it would stifle economic growth. By contrast, we economists are not suggesting that cars provide no benefits, or that driving should be eliminated. However, above an optimal level, increases in car use appear to impose more costs than benefits, even when considering a relatively narrow, market-oriented scope of impacts (when non-market costs such as pollution, equity, and declining quality of life are considered, the optimal level of car use is even lower).

Businesses in car-dependent communities have greater overhead costs. They must pay higher salaries to account for the higher cost of living, are burdened with increased costs for employee and customer parking facilities, and additional taxes for roads. These additional overhead costs are worse for the economy than a tax because they are true resource costs, not just economic transfers.

In a community with a long history of road building, car use appears to experience diseconomies of scale due to increasing congestion and other externalities. Each driver benefits if others drive less, reducing demand for road space and parking. There are probably few, if any, further economies of scale in car, petroleum and roadway industries.

There is no reason to believe that car expenditures provide more jobs or higher profits than expenditures on other consumer goods. Because a very large proportion of fuel and car assembly is imported, money spent on fuel and vehicles provides relatively little employment in a community...Only 15% of gasoline expenditures remain in the local economy...A region's economy may benefit by selling vehicles or fuel to other regions, but not by increased consumption of such goods within the region.

Many countries experience their greatest periods of economic growth when per capita car travel is relatively low, while growth rates decline as households become wealthy enough to afford personal cars.

Empirical evidence suggests that the ability of each transportation technology to operate at top efficiency strongly depends on a balanced infrastructure which provides transportation choices. User can therefore choose the most efficient way to make a particular trip. A car-dependent system makes the entire transportation system less efficient.

In an auto-dependent community, road and parking capacity are high, individuals have little transportation choice, transit is not cost-effective, land use patterns are relatively sprawled and dispersed, non-car travel is stigmatized, and transportation planning is single-mindedly focused on auto-oriented strategies.

Car-dependent cities spend the most on transportation, have to subsidize their transit the most, bear the greatest indirect costs such as road crashes and pollution, and overall are committing a higher proportion of their wealth for non-productive passenger transportation...Cities with transportation choices gain an economic competitive advantage by reducing the total proportion of wealth that must be devoted to transportation. Conversely, excessive car use drains wealth from a city.

Once a road system becomes congested and land values have risen, there are significant diseconomies from increased auto use, since it becomes extremely expensive to increase roadway capacity.

An analysis of 70 American metro areas found that regions which invested heavily in road capacity expansion fared no better in reducing congestion than those that invested less in road capacity.

A new highway intersection may attract businesses to a specific location, but this often simply represents a shift of economic activity from one location to another, rather than creating true economic development.

Auto dependency reduces travel choices for disadvantaged people, and is therefore inequitable.

High levels of car use leads to less efficient land use patterns that require more travel for a given level of access. Cities with transportation choice can have a higher quality urban environment downtown and in outlying centers.

Public transit expenditures provide twice the return on investment as highway modifications.

Federal and state road construction grants appear to be "free" money that provide local jobs and business activity during the construction period, and are therefore attractive regardless of their long-term transportation impacts. This is distortive and therefore inefficient.

Free parking that "leverages" car communting may benefit car dealers, mechanics and gas stations, but it disadvantages the bus system, bicycle shops, and other businesses where consumers spend money they save from less expensive transportation: Housing contractors, restaurants, clothing stores, etc.

There appear to be few external benefits of car-oriented land use (such that a non-driver or people from other communities benefit from car-oriented land use patterns).

Car use provides many benefits, but like any economic activity, there is an optimal level of car travel consumption beyond which marginal costs exceed marginal benefits...Although less driving would reduce economic activity in the car industry, the resources saved would be available for investment in other sectors, leading to a net increase in total economic activity. The car industry is mature and overcapitalized, with little potential for growth or high profits.

Todd Litman (1999). "Automobile Dependency and Economic Development." Victoria Transport Policy Institute.

In a car-dependent city without transportation choices, non-drivers face many obstacles, including limited choices, high financial and time costs, and poor service. Such people end up traveling less, foregoing some trips altogether.

If you have ever considered walking or bicycling to a destination, but decided not to because of heavy traffic along that route, you have experienced a cost of car dependency...The current transportation planning process overemphasizes vehicle traffic congestion problems, and increased road capacity solutions.

Auto underpricing is a major contributor to auto dependency. Consumers currently have little incentive to use transportation resources efficiently or equitably. About a third of total auto costs are external (not paid by the motorist). Only a quarter of the costs are paid by the motorist and are fixed (the purchase of the car or car insurance, for example). Once you pay those fixed costs, it is rational for you to want to use your car as much as possible in order to "get your money's worth."

Current transportation pricing is like an all-you-can-eat-for-one-price restaurant offering unhealthy food and low prices due to partial public funding. The result is waste and inequity because those who consume the most gain the most subsidies. Advocates of the status quo often argue that car dependency reflects consumer choice, but the evidence shows the opposite. If motorists paid directly for more of their costs, people would drive less and there would be more travel choices.

By not directly charging motorists to use roads, we overinvest in roads and increase car dependence...Auto-dependent conditions encourage low-value car trips, such as driving across town during rush hour to rent a video...People with abysmal driver safety records are frequently allowed to drive because there are so few travel options to the car.

Despite relatively low costs for fuel and cars, auto dependency in the U.S. forces households to spend a relatively large amount on travel. U.S. households spend more than 17% of their total expenditures on cars, making it the second largest household expenditure after housing. This proportion has grown substantially (in 1901, only 1 or 2% of household expenditures went into transportation).

A car-dependent city imposes substantial costs on the poor, because it increases the amount of car ownership and maintenance costs of the lower-income household. (households must own more cars, and each car costs approximately $6,500 per year to own). As Will Rogers once said, the U.S. may be the first society that drives itself to the poorhouse.

Car dependency hurts people who are already hurting. Car dependency is especially inequitable because people who are economically and physically disadvantaged bear an inordinate share of costs, while people who are advantaged enjoy an unequal share of benefits (vertical inequity)

People tend to spend about the same amount of time traveling no matter what their form of travel is, or what their average speed is. When our travel speed increases, we still have to make the same amount of contacts-we still work, eat, sleep and play in the same proportions as always. But with higher travel speeds, we simply do these further apart from each other.

A popular assumption is that auto expenditures benefit the economy...but it is production and export of goods that provides economic benefits, not consumption.

$1 million spent on petroleum provides only 4.5 jobs. The same amount spent on cars provides 7.5 jobs. That amount spent on transit provides 21.4 jobs.

Transportation accounts for only about half portion of the GNP in Japan as in the U.S. This increases Japanese productivity and frees funds for capital investment.

Todd Litman (1999). "The Costs of Automobile Dependency." Victoria Transport Policy Institute.

In general, policies and programs that reduce transportation costs increase economic competitiveness and development...It represents a significant portion of total costs in many resource-based industries, and so a modest change in transportation costs can have a major impact on profitability.

External transportation costs not paid by motorists: pollution, congestion, parking, land, and uncompensated crash costs.

If you increase your travel from 5 to 10 car trips a week, each additional trip will probably provide significant benefits. But if you increase travel from 5 to 10 car trips per day, the value of the additional trips will probably be small because they consist of increasingly less valuable trips. A certain amount of mobility provides significant economic benefits, but that does not mean that more mobility is always better. There is an economically optimal level of car use beyond which increased driving is overall harmful to society.

The best way to determine optimal consumption levels is to let consumers decide in an efficient market-consumers have choices, competition, and pricing that accurately reflects costs. The U.S. transportation system contains severe pricing distortions that violate these market principles and do not allow us to realize optimal transportation consumption. Underpriced roads, fuel and parking means that motorists inefficiently use them because the price does not reflect the costs-too many of the costs are subsidized or externalized. The result is excessive (more than would occur in an efficient market) car use, traffic congestion, pollution, sprawl, and crashes, among other things...These added costs are equivalent to a tax on businesses and consumers that reduces productivity.

This is not to suggest that car use is bad or would stop in a more efficient transportation market. Car travel is often an efficient travel option. But cars are often used in inefficient ways, due to market distortions.

A major study for the World Bank that compared economic development patterns and transportation in various cities throughout the world indicates that excessive car use tends to reduce regional economic development...Regions with transportation choices appear to be the most economically productive and competitive...During the 1960s and 1970s, Japan devoted only 10% of GDP to transporatation, compared to 18% in the U.S., and that the savings were approximately equal to the higher rate of investment in Japan, a significant factor in Japan's higher rate of economic growth during that period.

That transportation is essential to economic activity does not mean that more transportation is necessarily better, roadway projects are optimal investments, or underpricing is justified. Economic analysis must reflect net marginal benefits, that is, the incremental benefits of an additional unit of transportation activity, taking into account both costs and benefits...Once a region has a basic paved road system, additional roadway capacity provides relatively small economic development benefits. Most impacts that do occur are economic transfers, economic activity shifted from one location to another without overall gain. Increased highway capacity often provides economic benefits in one part of a region at the expense of other areas.

Transportation investments in transit or programs to reduce low-value car travel can provide greater economic benefits than increased roadway capacity...Thousands of dollars would need to be spent annually per household to increase roadway capacity enough to simply maintain current congestion levels.

A consumer dollar spent on cars means one less dollar for housing, food, entertainment, education, or investment...$1 million spent on cars creates 8.4 jobs. For non-car consumer expenditures, 17 jobs are created regionally. When spent on transit, 62.2 jobs are created...Policies which reduce consumer expenditures on cars and fuel tend to increase employment and business activity, particularly in regions that import oil.

In more auto-dependent American communities, households devote more than $8,500 annually to travel, and in those with more transportation choices, less than $5,500 is devoted annually...$10,000 spent on cars provides just $910 in equity, compared to $4,730 for the same investment in housing, indicating that policies which allow consumers to shift spending from car travel to other expenses such as housing or education tends to create wealth.

Todd Litman (2001). "TDM and Economic Development." Victoria Transport Policy Institute.

Success Stories of Putting City Roads on a Diet

"In the early nineties, cars sped down six wide lanes [in downtown Lake Worth FL]... In the early nineties, Lake Avenue...was in decline. Many businesses moved out. Antique dealers of varying quality and empty storefronts were about all that remained. Traffic accidents-vehicular and pedestrian-were on the rise." Design and transportation experts Victor Dover, Dan Burden, and Michael Wallwork were hired. Their idea of narrowing Lake Avenue was met with skepticism. The redesign of Lake Avenue included taking the six-lane street down to 4 lanes in some portions and 2 lanes in other portions, with wider sidewalks and on-street parking added. "Despite initial misgivings, the Lake Worth business community is now singing the praises of the redevelopment effort...the taxable value of nonexempt properties in the Community Redevelopment Agency district went up $6.3 million, some 6.5 percent [within a few years of the street redesign]. "A new bank and restaurant, a changed mix of retailers, and façade improvements have all occurred quickly. Retail vacancies are down to virtually zero...The Florida Department of Transportation is trying to institutionalize this approach in its Transportation Design for Livable Communities Project."

[Note: According to Gene Nowak, Lake Worth city planner, there has been a 10 percent increase in property values along Lake Avenue for each of the past 2 years after the street was redesigned.]

"Lake Worth: Reclaiming a Small Downtown." By Cynthia Pollock Shea, Contributing Editor, Florida Sustainable Communities Network. 10/28/98.

A 1999 study has found that homebuyers were willing to pay a $20,000 premium for homes in pedestrian-friendly communities compared to similar houses in the area that were designed in conventional neighborhoods...Another study found that a 5 to 10 mph reduction in traffic speeds increased adjacent residential property values by roughly 20%...Hewlett Packard halted its planned expansion in Atlanta's Perimeter Center because it did not want to subject 1,000 new employees to the area's serious traffic problems [Atlanta is nationally notorious for spending billions to widen highways, and by doing so has created some of the nation's worst sprawl, some of the most serious lack of transportation choices, and some of the nation's worst congestion.]...The Southern California region is expected to spend more than a trillion public and private dollars on roads and freeways between 2000 and 2020, yet rush hour congestion is still expected to rise approximately 330 percent.

Local Government Commission. Center for Livable Communities. "Economic Benefits of Walkable Communities." Sacramento CA.

In West Palm Beach FL, "The car was fine, but our city was dead 10 years ago. The street became the monopoly of the car to the exclusion of pedestrians." In downtown, on Clematis Street, the street was converted from a one-way, four-lane street to two-way traffic. On-street parking was installed, as were landscaped bulb-outs and street trees to slow traffic. The change won support from initially skeptical business groups. Property values have risen from $10-$40 per square foot to $50-$100 per square foot. Commercial rents have risen from $6 per square foot to $30 per square foot in downtown areas that have been traffic calmed. Once half-occupied, commercial buildings now have no vacancies. And downtown is becoming a popular place to live. In one portion of the street the street was narrowed from 3 lanes to 2 lanes with on-street parking. Rents increased from $6 per square foot to $30 per square foot. Occupancy increased from 80% vacancy to 20% vacancy. The project has attracted some $350 million in private investment to the area. The amount of off-street parking is being reduced each year...On Northwood Road, a major intersection was reconstructed with brick pavers. The approaches to the intersection were narrowed to reduce pedestrian crossing distance and create space for landscaping. Traffic signals were removed. Cut-through traffic has been reduced and speeding along Northwood Road no longer occurs. Pedestrian traffic has increased. Private investment has begun to return to the area.

City of West Palm Beach (1998). "Traffic Calming Reference Materials." Ian Lockwood and Timothy Stillings. October.

In South Orange NJ, a four-lane arterial had an excessive number of speeding cars racing past too few active storefronts. There was a feeling that the street was cutting the village in half. To slow the flow, engineers widened sidewalks, created on-street parking, and created turn lanes. The change shrunk the roadway to one lane in each direction.

Engineering News Record (1998). "Taking Back Main Street." January.

Other successful diets

Lake Washington Blvd, Kirkland WA (4 lanes to 2 w/ middle turn lane & bike lanes)
Electric Avenue, Lewistown PA (4 lanes to 2 w/ middle turn lane & bike lanes)
Burcham Road, East Lansing MI (4 lanes to 2 w/ middle turn lane & bike lanes)
Grand River Boulevard, East Lansing MI (4 lanes to 2 w/ middle turn lane & bike lanes)
St George St, Toronto, Ontario Canada (4 lanes to 2 w/ bike lanes and wide sidewalks)
120^th Avenue, NE Bellevue WA (4 lanes to 2 w/ middle turn lane)
Montana Street, Bellevue WA (4 lanes to 2 w/ middle turn lane & bike lanes)
Main Street, Santa Monica CA (4 lanes to 2 w/ middle turn lane & bike lanes)
Danforth Street, Toronto, Ontario Canada (4 lanes to 2 w/ middle turn lane & bike lanes)
Greenwood Avenue, Seattle WA (4 lanes to 2 w/ middle turn lane & bike lanes)
N 45^th Street, Seattle WA (4 lanes to 2 w/ middle turn lane)
8^th Avenue NW, Seattle WA (4 lanes to 2 w/ middle turn lane)
Martin Luther King Way, Seattle WA (4 lanes to 2 w/ middle turn lane & bike lanes)
Dexter Avenue N, Seattle WA (4 lanes to 2 w/ middle turn lane & bike lanes)
24^th Avenue NW, Seattle WA (4 lanes to 2 w/ middle turn lane)
Madison Street, Seattle WA (4 lanes to 2 w/ middle turn lane)
West Government Way/Gilman Avenue, Seattle WA (4 lanes to 2 w/ middle turn lane & bike lanes)

Dan Burden and Peter Lagerwey (1999). "Road Diets-Fixing the Big Roads." Walkable Communities, Inc.

Can we build our way out of congestion?

One of the most comprehensive new studies covers 30 urban counties in California from 1973 to 1990. The authors found that at the metro level, every one percent increase in road capacity creates a 0.9% increase in traffic within four years-a phenomenon known as "induced traffic," wherein new car trips are "induced" by the widening and would have never occurred had there been no widening.

Hank Dittmar (1998). "Do New Roads Cause Congestion?" Surface Transportation Policy Project. March 1998.

The traditional approach has been to accommodate travel demands by increasing supply [primarily by adding travel lanes or turn lanes]. However, demand continually exceeds supply. As capacity is added to the transportation system, either by expansion or by the introduction of more efficient means of travel, it is always consumed.

A 1997 study found that consistently, people devote an average of 1.1 hours per person per day to travel. African villagers, the middle class and the super rich, who travel by foot, car, or plane all have similar travel time budgets. Changes to the community transportation system that result in changed travel speed (from train to car, from widening a road, increased congestion, etc.) result in changes people make in their daily travel in order to maintain the 1.1-hour average. Thus, widened roads induce car trips, which triggers traffic engineers to widen, which induces more trips, which triggers more widening, and so on in a vicious cycle. In addition, the widening also encourages people to live in more dispersed, sprawling residential locations, since it is now possible to live further from work and still maintain the travel time budget of 1.1 hours. Likewise, a street carrying slower traffic discourages (low value) car trips during rush hour, and encourages people to live closer to work or town

...in the 1990s, the prevailing wisdom among urban planners and designers is that a busy street, a somewhat congested street, is an indicator of a healthy business environment. Moving cars into and/or through downtown is no longer the objective. The new objective is to reduce speeds...to a level that is compatible with pedestrian traffic...In a reversal of past thinking, it is now understood that traffic moving at high speeds downtown is a symptom of a downtown decline problem...

One of the advantages of a downtown is that it provides a variety of goods and services in a relatively compact area. By converting some of this compact area to off-street surface parking, we either remove goods and services or displace them. In either event the loosening of the compact land use minimizes one of the advantages of downtown. We have come to realize that with respect to downtown parking, we need to minimize off-street parking in order to maintain compact form.

The construction of surface parking lots in many instances has little to do with the need for more parking downtown. High property taxes have caused many owners to demolish their buildings (thus lowering taxes) and providing surface parking lots while waiting for the economy to improve. Empty surface lots, besides affecting the compactness of the downtown, also give the downtown a look and feel of desolation.

On-street parking is preferred to off-street parking because it (1) uses road space that has been traditionally used to move traffic; (2) minimizes pedestrian-vehicle conflicts; (3) minimizes the need for off-street parking which reduces the compactness of the downtown; (4) acts as a buffer, or physical barrier, between pedestrians and moving cars; (5) increases usable sidewalk space; and (6) provides friction that reduces the speed of moving vehicles.

Gerald Forbes (1998). "Vital Signs: Circulation in the Heart of the City-An Overview of Downtown Traffic." ITE Journal. August.

A Florida Economist on Road Capacity and Congestion

In June 1989 in Orlando, professor Ronald G. Holcombe of Florida State University made the following comments regarding road concurrency in the State Growth Management Law. In general, they track what Anthony Downs had to say regarding his "triple convergence" theory:

One implication is that levels of service, as defined by Florida Administrative Code Rule 9J-5, may be impossible to implement. Road [widenings] intended to raise the level of service could result in increased levels of traffic instead.

It could make sense to have temporarily lower levels of service in areas of new development.

More congestion would make it easier to implement mass transit in an area. Mass transit could improve levels of service without direct roadway [capacity increases].

...Economic principles suggest that people should pay for the infrastructure they use. This imposes costs on users, causing them to take account of the costs of their own actions. One implication is that gasoline taxes are a better source of revenue for roadway [modifications] than other sources such as sales (or income) taxes.

...the last development built that adds traffic to a road is not the development that causes the congestion. All traffic on the road, whether from new or old developments, are equally responsible for the congestion on roads...If this principle is not adhered to, it creates a common pool problem (with the arterial road being the common pool). Everyone has an incentive to develop property too fast so as not to be the one who is charged for congestion on the roads. Thus, a policy of taxing new development more than existing developments for common infrastructure will lead to overly rapid development, helping to cause congestion problems that the policy is intended to solve.

This will make it impossible in some areas to alleviate congestion by enlarging capacity. There is a fallacy that sometimes creeps into highway planning that a given amount of development will create a given amount of traffic. In fact, the amount of traffic created by a given development depends upon how costly it is to use the roads. The mere act of enlarging capacity will create congestion without additional development by reducing the incentive to avoid peak hour travel, creating the incentive to take more trips, and reducing the incentive to live close to work. Congestion is a cost that rations roadway use, and it follows that unless tolls are charged, congestion cannot be eliminated from intensely populated areas by enlarging roads.

Remove It and They Will Disappear

New evidence from a British study shows that closing streets [removing travel lanes] can eliminate traffic. The study analyzed 60 cases worldwide, and found that from 20 to 60 percent of the pre-existing car trips disappeared when travel lanes were removed. Only a portion of the reduction is due to diversion to nearby streets. Many are simply a shift in time-of-day for the trip, or a shift to another form of travel.

Jill Kruse (1998). "Do New Roads Cause Congestion?" Surface Transportation Policy Project. March 1998.

The Triple Convergence, by Anthony Downs

Nearly every vehicle driver normally searches for the quickest route, one that is shorter or less encumbered by obstacles (such as traffic signals or cross-streets) than most other routes. These direct routes are usually limited-access roads (freeways, expressways, or beltways) that are faster than local streets if they are not congested. Since most drivers know this, they converge on such 'best' routes from many points of origin.

The problem is that during the peak travel hours on weekdays, so many drivers converge on these 'best' routes that they become overloaded, particularly in metropolitan areas. Traffic on them eventually slows to the point where they have no advantage over the alternative routes. That is, a rough equilibrium is reached, which means that many drivers can get to their destinations just as fast on other roads. At times, the direct road may become even slower than alternative streets, and some drivers eager to save time will switch to them. Soon rough equality of travel times on both types of route is restored at the margin. The opposite happens if travel becomes slower on alternative streets than on the expressway.

Such observations can be made about this equilibrium situation: (1) it tends to recur, because most drivers develop habitual travel patterns; (2) during equilibrium each limited-access road is carrying more vehicles per hour than each normal city street or arterial route because it has more lanes, more direct routing, and fewer obstacles; (3) many drivers time their journeys to miss these periods because they do not like to waste time in heavy traffic; and (4) at the peak of equilibrium, traffic on most expressways is crawling along at a pace far below the optimal speed for those roads, as explained below. Now suppose that the limited-access route undergoes a vast improvement-its four lanes are expanded to eight. Once its carrying capacity is increased, the drivers using it move much faster than those using alternative routes. But this disequilibrium does not last long because word soon gets around that conditions on the expressway are superior.

In response, three types of convergence occur on the improved expressway: (1) many drivers who formerly used alternative routes during peak hours switch to the improved expressway (spatial convergence); (2) many drivers who formerly traveled just before or after the peak hours start traveling during those hours (time convergence); and (3) some commuters who used to take public transportation during peak hours now switch to driving, since it has become faster (modal convergence).

The triple convergence causes more and more drivers to use the improved expressway during peak hours. Therefore its traffic volumes keep rising until vehicles are once again moving at a crawl during the peak period. This outcome is almost inescapable if peak-hour traffic was already slow before the highway was improved. If traffic is going faster than a crawl on this direct route at the peak hour, its users will still get to their destinations faster than users of city streets, which are less direct and more encumbered by signals and cross-streets. Total travel times on these two types of paths will only become equalized if the limited-access roads are so overloaded that vehicles on them are moving at slower speeds than those on normal streets. Triple convergence creates just such an effect during peak hours...

...In any event, expanding roadway capacity does not fully eliminate peak-hour traffic congestion, or even reduce the intensity of traffic jams during the most crowded periods-although those periods will be shorter. In fact, it is almost impossible to eradicate peak-hour traffic congestion on limited-access roads once it has appeared within a nonshrinking community. In theory, such congestion could be eliminated only if the capacity of those roads were increased to the extent that they could carry every single commuter simultaneously at the peak minute at, say, 35 miles per hour or faster. In nearly all metropolitan areas, that is impossible. Therefore, expansions of road capacity-no matter how large, within the limits of feasibility-cannot fully eliminate periods of crawling along on expressways at frustratingly low speeds."

Widening Roads Worsens Traffic Congestion

by Tanya Albert, January 13, 2000, The Cincinnati Enquirer

CINCINNATI-Widening and building new highways actually causes, not relieves, traffic congestion in Cincinnati and other major U.S. metropolitan areas, according to a new study presented today to the 79th Annual Transportation Research Board in Washington, DC. The study estimated that up to 43% of traffic in Greater Cincinnati is caused just by expanding the area's road network. The study also says that Tri-State traffic congestion would have grown less rapidly if no new or wider highways were built at all, contrary to what highway planners have predicted.

The study, "Analysis of Metropolitan Highway Capacity and the Growth in Vehicle Miles of Travel," used data from the Texas Transportation Institute's most recent database for 70 urbanized areas from 1982-1996. Using three models with different variables, the study found that highway-induced traffic in the Cincinnati area (including Northern Kentucky) increased by 14%-43%. Highway-induced traffic estimates for nearby metropolitan areas were 12%-35% in Columbus; 13%-30% in Cleveland; 20%-50% in Indianapolis; and 34%-77% in Louisville. The national average was 15%-45%.

"Simply put, this study adds to the growing evidence that traffic congestion has been made worse, not alleviated as road builders claim, by more and bigger highways. It follows that to reduce traffic congestion, and therefore air pollution and suburban sprawl, we need to stop building and widening sprawl-causing highways," said Glen Brand, director of the Cincinnati office of the National Sierra Club. "Instead it would be smarter to plan our communities better so that we aren't forced to drive everywhere, and to provide greater transportation choices such as commuter light rail and expanded bus service."

The study's authors, Robert Noland, University of London Center for Transport Studies and William A. Cowart, ICF Consulting in Fairfax, VA., conclude that "induced travel effects strongly imply that pursuit of congestion reduction by building more capacity will have short-lived benefits. This may be evidence for a strong sprawl inducing impact of large increases in lane mile capacity relative to the existing infrastructure.

Recognition of these impacts implies that the benefits of new highway construction are less than would be calculated from a static analysis that included no induced travel impacts."

Currently, highway expansion is occurring all over the Tri-State, including widening of I-71 and I-75, the new Butler County Regional Highway, and a proposed Eastgate highway in Clermont County.

"In the light of this new research, policy-makers, including County commissioners and engineers, Ohio Department of Transportation, and Ohio-Kentucky-Indiana Council of Regional Governments, need to re-calculate the benefits and costs of highway expansion, said Sierra Club's Brand. "We are calling for a balanced transportation program that spends as much on travel choices such as clean buses and light rail trains as on building new sprawl-and-congestion-causing highways."

Haynes Goddard, Professor of Economics at the University of Cincinnati with expertise in transportation economics, said that "this study is a careful statistical analysis of the perverse effects of insufficiently considered highway investments, and how they can make our region a less desirable place to live. It makes it clear that putting all of our proverbial transport eggs in the highway basket reduces the economic vitality of our region".

One study in Oregon showed that by planning development so that people have easy access to commuter trains and other public transportation choice, traffic for new development can be reduced from 10 car trips per day to 6 trips per day.

"If people are tired of being stuck in sprawl mall traffic, we need to promote smarter planning and increase travel choices, not just build [wider] highways," said Brett Hulsey, coordinator of the Sierra Club Challenge to Sprawl Campaign. "More roads lead to more traffic like bigger pants tend to lead to more weight gain. We need to change our philosophy to reduce, not increase sprawl and traffic."

The Sierra Club is calling on state and local leaders to spend at least half of their transportation money on safety improvements to existing streets and roads, and for public transportation alternatives, and promote traffic impact analysis on new sprawl development, and good planning measures to minimize traffic.

Ian Lockwood, April 8, 2004

The conversion of Winter Park Mall into Winter Park Village (Florida) is a clear example of a better walking environment that helped one of the least successful retail areas in Central Florida become one of the most successful…that success is leading to several other changes in the area of Winter Park Village that will spread the walkability and economic success. The changes to Clematis Street [in West Palm Beach FL] had a huge effect as well: 80 percent [commercial] vacan[cy] to almost [100 percent occupied] (even though the street could be better). The Clematis Street changes resulted in private investment in the area that was many times higher than the cost of the project and was one of the first projects to help turn around the city economically.

However, in Canada, one of the best case studies would be Ottawa. Ottawa was not blessed with great weather, topography, or network planning…through concerted efforts, that city now has a connected system of bicycle and pedestrian facilities, linear parks, and bus facilities. Pedestrian access to the bus systems was key. Land use changes and facilities were made. Today, a ten-year-old can easily get around Ottawa on foot, by bike, or on the bus. The modal split to the downtown and CBD has changed to the point where car users are in the minority. The economic savings and economic benefits through tourism etc. must be staggering. Just the land costs saved by not having to build so many car parking facilities must be huge.

Back to the Walkable Streets home page.