Automobile Dependency

Transportation and Land Use Patterns That Cause High Levels of Automobile Use and Reduced Transport Options


TDM Encyclopedia

Victoria Transport Policy Institute


Updated 31 August 2014

This chapter describes Automobile Dependency, its causes and implications.



Defining and Measuring Automobile Dependency

Automobile dependency (also called automobile oriented transportation and land use patterns) refers to transportation and land use patterns that favor automobile access and provide relatively inferior alternatives (in this case, “automobile” includes cars, vans, light trucks, SUVs and motorcycles). It means that people find it difficult to reach services and activities without using an automobile.


The alternative to Automobile Dependency is not a total lack of private vehicles (called Carfree Planning), rather, it is a multi-modal transport system (often called Transit-Oriented Development), meaning that people have various Transport Options from which to choose, that these options are integrated effectively to provide a high degree of accessibility even for non-drivers. This allows people to use the best mode for each trip: walking and cycling to reach local destinations, public transport for travel on major travel corridors, and automobile when it is truly optimal.


Automobile Dependency is a matter of degree. Table 1 compares various attributes of Automobile Dependency . There are few places in the world that are totally automobile dependent (that is, driving is the only form of transport). Even areas that appear to be highly Automobile Dependent often have a significant amount of walking, cycling and transit travel among certain groups or in certain areas, although use of these modes tends to be undercounted by conventional transportation planning (Measuring Transportation).


Table 1            Attributes of Automobile Dependency






Popular Name




Automobile Dependent

Vehicle Ownership

Per capita motor vehicle ownership (usually measured per 1,000 population)

Less than 250 per 1,000 pop.



Vehicle Travel

Per capita annual motor vehicle mileage

Less than 4,000 miles (6,500 km)

4,000-8,000 miles (6,500-13,000 kms)

8,000+ (13,000 km plus)

Vehicle Trips

Automobile trips as a portion of total personal trips

Less than 50%



Quality of Transportation Alternatives

Convenience, speed, comfort, affordability and prestige of walking, cycling and public transit relative to driving.

Alternative modes are of competitive quality.

Alternative modes are somewhat inferior.

Alternative modes are very inferior.

Relative Mobility Of Non-Drivers

Mobility of personal travel by non-drivers compared with drivers.

Non-drivers are not severely disadvantaged.

Non-drivers are moderately disadvantaged.

Non-drivers are severely disadvantaged.

Land use patterns

Land use density (residents and jobs per acre) and mix (proximity of different land use types).

Very compact and mixed.

Moderately compact and mixed

Dispersed and homogenous

Transport system

Type of transportation facilities and services available.

Mainly nonmotorized and public transit

Very mixed: nonmotorized, public transit and automobile.

Mainly automobile (roads and parking facilities).

Roadway design

Design features of public roads.

Highly pedestrian oriented


Designed to maximize auto traffic speeds and volumes.

Shopping Options

Where retail and other public services are located

Along public streets

Mainly along public streets near transit areas

In private malls, located along major highways

Market Distortions Favoring Automobile Use

Relative advantage provided to automobile transportation over other modes in planning, funding, tax policy, etc.

Minimal bias favoring automobile travel.

Moderate bias favoring automobile travel.

Significant bias favoring automobile travel.

Automobile commute mode split

How people travel to work and school.

Less than 35%


More than 65%

Errand travel

How people normally travel to stores, professional appointments, recreation activities, etc.

Mostly walking, cycling and public transit.

Walking, cycling, public transit and automobile.

Mostly automobile.

Performance Indicators

How transport system performance is evaluated

Quality of walking, cycling and public transit



This table summarizes various indicators of automobile dependency.



In an automobile dependent transportation system, automobile travel becomes “compulsory” due to inadequate alternatives (Soron 2009). As a result, virtually every adult is expected to have a personal automobile (as opposed to a household automobile shared by more than one driver). Non-drivers must be chauffeured, and it becomes difficult to withdraw driving privileges for people who are physically, mentally or emotionally unfit, since there are few viable transportation alternatives. Automobile Dependency reduces the range of solutions that can be used to address problems such as traffic congestion, road and parking facility costs, crashes and pollution.


Automobile Dependent transportation system imposes significant costs and constraints that in many ways reduce independence and freedom (Conley and McLaren 2009):

·         It requires high rates of vehicle ownership, fuel consumption, and demand for roads and parking facilities, which increases total transport costs to consumers and society.

·         Wide roads and vehicle traffic degrade the pedestrian environment and create a barrier to nonmotorized travel

·         By stimulating sprawled development it reduces land use Accessibility, so more mobility is required to participate in economic and social activities.

·         It imposes external costs, including facility costs, health risks and environmental damages.

·         It tends to make non-drivers worse off, and so exacerbates social inequity.



Most North American communities are relatively automobile dependent: The majority of households own automobiles and rely on them for most trips. Land use patterns are easily Accessible by automobile but not by other modes. Public policies favor automobile travel, and few resources are devoted to non-automobile transportation. Although consumers have many choices when choosing an automobile and vehicle services, they often have few viable alternatives to driving for mobility.


Experiencing Automobile Dependency

If you are a typical motorist, try this experiment: Give up driving for two typical weeks. This period should require normal travel for work, shopping, socializing and family obligations. You’ll discover that non-drivers face many obstacles, including limited travel options, high financial and time costs, and poor service. As a result you may travel less, foregoing some trips and choosing more convenient destinations for others. You may experience embarrassment when asking for a ride or when you use stigmatized modes such as transit, bicycling and walking.


The problems you experience as a non-driver depend on where you live. If your community is highly automobile dependent you will experience significant difficulties. You may have trouble getting to a store or even crossing busy streets. If your community is multi-modal, with good transit service, bicycle and pedestrian facilities, you may experience few problems.


After two weeks you may be glad to drive again. You may also have experienced some benefits during the period of abstinence. You may discover unexpected joys from walking and bicycling, reduced stress, increased exercise, and friendship with fellow car pool or transit passengers. You may have appreciated being more home-centered and community oriented. You may take pride in reducing pollution, and saving energy.



As a community becomes more automobile dependent, the people who rely on alternative modes becomes an increasingly small minority, so decision-makers become less familiar with their needs and their political influence declines. As a result, countless public policy and planning decisions become more favorable to automobile travel, and less consideration is given to supporting other modes.


Until recently, public officials and transportation professionals generally considered Automobile Dependency acceptable or even desirable. They assume that Automobile Dependency reflects consumer preferences and is inevitable with increased wealth. They associated automobile travel with comfort, convenience, success and economic development, and alternative modes with deprivation and failure. Most had no experience with efficient, multi-modal transportation systems.


But this assumption is increasingly questioned. Although automobile transportation provides significant benefits to society, these benefits experience diminishing marginal returns. Beyond an optimal level, increased motor vehicle traffic provides little additional benefits, while imposing increasing costs, and reducing the viability of other transport modes. These diminishing marginal benefits occur at both an individual level (although a consumer may benefit from driving 10,000 annual vehicle-miles, few would want to drive 100,000 annual vehicle-miles regardless of how low their financial cost), and at the community level (although a certain amount of vehicle traffic is contributes to economic and social activities, increased vehicle traffic does not necessarily cause more economic and social development). Automobile Dependency is harmful overall because it represents levels of automobile use beyond what is economically and socially optimal (Litman 2000).


Automobile ownership and use tend to increase with wealth up to a point, but they eventually reach saturation. An international study found that per capita automobile ownership peaks at about $21,000 (1996 U.S. dollars) annual income and levels off, or even declines due to increased congestion, loss of novelty, and public policy responses (Talukadar, 1997). Using U.S. data, Holtzclaw (2000) found that vehicle travel increases strongly with annual income up to about $30,000, but then levels off and declines slightly with incomes over $100,000. Increased wealth allows consumers to choose alternatives to driving. For example, some wealthy commuters prefer using transit rather than driving, provided that the service is comfortable, convenient and reliable. Similarly, many wealthy people value living in more accessible neighborhoods, where they are close to commercial and cultural activities, and can walk and bicycle for both recreation and transportation (New Urbanism).


Why Not Drive?

Driving is often the fastest mode of travel, and although automobiles are expensive to own (considering fixed costs such as depreciation, insurance, registration fees, scheduled maintenance and residential parking expenses) they are relatively cheap to drive, typically costing just a few cents per mile in operating expenses. Automobile travel also tends to be more comfortable and prestigious than other modes. This explains why 70-90% of trips are made by automobile (depending on definitions and conditions).


But for various reasons travelers often need or prefer travel by alternative modes:

·         Many people cannot drive. In a typical community, 20-40% of the total population, and 10-20% of adolescents and adults, cannot drive due to disability, economic, age constraints, or vehicle failures. Inadequate transport options reduces non-drivers ability to access activities and forces motorists to chauffeur non-drivers (according to the 2009 National Household Travel Survey, 5% of total trips were specifically to transport a passenger).

·         Many people should not drive for some trips, due to inebriation, disability, or economic constrains. For example, efforts to reduce driving by higher-risk groups (people who are impaired by alcohol or drugs, young males, or people with dementia) can only be successful if there are good alternatives to driving. The high costs of automobile transport places a major financial burden on many lower-income people.

·         Travelers sometimes prefer using alternative modes, for example, because walking and cycling are more enjoyable and provide healthy exercise, or public transit commuting imposes less stress and allows commuters to read, work or rest.

·         Society could benefit from more efficient road, parking, fuel and insurance pricing, or more efficient management of road space, that favor higher value trips and more efficient modes in order to reduce traffic congestion, parking costs, accidents and pollution emissions.



It is therefore interesting to consider what mode share is overall optimal to users and society, and the portion of automobile travel that occurs because travelers lack suitable alternatives. For example, if walking and cycling conditions, and public transit service quality were better, how much more would people rely on these mode, and how much less automobile travel would occur?


In fact, walking, cycling and public transit travel do tend to be much higher, and automobile travel is much lower, in communities with better transport options. For example, Guo and Gandavarapu (2010) estimate that completing the sidewalk network in a typical U.S. town on average increases non-motorized travel 16% (from 0.6 to 0.7 miles per day) and reduces automobile travel 5% (from 22.0 to 20.9 vehicle-miles). Similarly, residents of transit-oriented communities tend to use alternative modes 2-10 times more frequently, and drive 10-30% fewer miles, than residents of automobile-oriented communities (Cervero and Arrington 2008; Litman 2009). Even larger travel reductions occur if improvements in alternative modes are implemented in conjunction with incentives such as more efficient road, parking and insurance pricing.


This indicates latent demand for alternative modes, that is, people would like to rely more on alternative modes but are constrained by poor walking and cycling conditions and inadequate public transit services. This is not to suggest that in an optimal transport system people would forego driving altogether, but it does indicate that given better transport options and more efficient incentives, people would rationally choose to drive less, rely more on alternative modes, and be better off overall as a result.



Factors That Contribute to Automobile Dependency

A number of transportation and land use market distortions tend to encourage automobile ownership and use, including underpricing, inadequate consumer choice, weak competition, bias in transportation planning and investment practices, and other public policies that favor automobile travel (Litman 2006; Brown, Morris and Taylor 2009).


During the last century there has been a self-reinforcing cycle of increased automobile travel, reduced travel options, and more automobile-oriented transportation and land use policies which result in a high level of automobile dependency in most communities (Turcotte 2008). Figure 1 illustrates this cycle.


Figure 1          Cycle of Automobile Dependency

Automobile dependency results from a self-reinforcing cycling of increased automobile ownership, reduced travel options and more dispersed automobile-oriented land use patterns.



Conventional Transportation Planning practices tend to create a self-fulfilling prophecy that supports this cycle: past traffic growth rates are extrapolated to predict future vehicle traffic demand, and road and parking capacity is built to meet this projected demand (called predict and provide planning). Little consideration is given to the negative impacts that more dispersed destinations, larger roads and parking facilities, and reduced resources for other travel modes will have on overall Accessibility. The result is increasingly automobile-oriented transportation systems and land use patterns (Condon, 2004). More Comprehensive Planning can help create more balanced transportation systems.


Transportation Evaluation practices often favor automobile dependency. Transportation service quality is often Measured primarily in terms of vehicle traffic (e.g., roadway level of service, average traffic speed, vehicle congestion delay), with little or no consideration to other modes. Nonmotorized Transportation tends to be undervalued in conventional transportation surveys and Models, which ignore or undercount short trips, travel by children, leisure travel, and walking links to access automobiles and transit service. As a result, few resources are devoted to walking and cycling.


Current investment practices also contribute to Automobile Dependency. Transportation funding is often dedicated to roads and parking, and cannot be used for other types of transportation facilities or services, even when they are more cost effective overall. Zoning codes often include minimum parking requirements, which represent a subsidy of automobile travel, and by increasing land requirements, results in lower-density, urban fringe development. Least Cost Transportation Planning, Smart Growth Policy Reforms and Parking Management are TDM strategies that can help correct these distortions.


Automobile use is considered Prestigious, while other mode are stigmatized, many urban communities have become unattractive to middle-class residents, and some people assume, incorrectly, that automobile dependency contributes to Economic Development. The public officials and community leaders most involved in transportation planning tend to be automobile dependent, and so are particularly conscious of problems facing motorists and less aware of problems facing people who depend on other modes. This is not to suggest that public officials are unconcerned about the negative impacts of increased vehicle traffic and problems facing non-drivers. Many work hard to improve Transport Options. However, this occurs despite, rather than supported by current transportation evaluation and planning practices.


While it may seem harmful to constrain road building just to reduce automobile dependency, a more positive perspective, which often reaches the same conclusion, is that once a community has a basic road system which provides motor vehicle access to most destinations, increasing traffic capacity and speed provides diminishing benefits and increasing costs, so it makes sense to invest an increasing portion of resources in alternative modes and more accessible land use patterns in order to achieve community planning objectives. There is a strong economic case for transportation and land use policies that increase the cost of driving (Market Reforms), reduce sprawl (Land Use Evaluation) and increase Transport Options (Litman, 2000).


No One Goes There Anymore. It’s Too Crowded.

By Peter Jacobsen


Does improving drivability improve economic wealth?


In 2003, Sperling's BestPlaces ranked 77 U.S. cities based on how easy it is for residents to motor around their city ( They say the most drivable cities have smooth driving surfaces, free-flowing traffic, low gas prices and a pleasant climate. Topping their list were cities along the Texas Gulf coast, whereas the poorest performing cities were along the East and West coast.


Curiously enough, the least drivable cities appear to be thriving economically. Comparing drivability against per capita income (Commerce Department shows that the average per capita income of the ten least drivable cities is over half again greater than the ten most drivable cities,, as illustrated below.


Figure 2          Annual Per Capita Income (MSN, 2003; BEA, 2003)

The ten U.S. communities ranked least sprawled have much lower average annual per capita incomes than the ten communities that are ranked most sprawled.



Although Yogi Berra was thinking of New York City nightclubs, he summed up the fallacy of using drivability as a measure of transportation policy decisions with his famous line: “No one goes there anymore. It’s too crowded.” No matter how much we personally dislike congestion, it measures economic vitality.



Travel Impacts

Automobile Dependency typically doubles automobile ownership and use, and associated Costs, including vehicle ownership and operating costs (and therefore the portion of household budgets devoted to transportation), road and parking infrastructure costs, per capita traffic fatality, energy consumption, pollution emissions and land use consumption. These impacts can be perceived by comparing travel patterns between transit-oriented and sprawled neighborhoods in U.S. cities (Figure 3), by comparing differences in travel patterns between multi-modal and more sprawled U.S. cities (such as between Davis, California where residents average 13.9 daily vehicle-miles and Houston, Texas where residents average 34.0 daily vehicle-miles), and by comparing U.S. travel patterns with those of other wealthy countries, such as Norway and Switzerland. For example, U.S. residents devote approximately 20% of household incomes to transportation (motor vehicles, public transit and residential parking), which is about twice the amount spent on average by Swiss residents. Interestingly, there are no measurable differences in the amount of time that people spend on transportation between multi-modal and automobile dependent locations; residents of more automobile-oriented communities are able to travel somewhat faster, but their destinations are more dispersed so they save no time overall.


Figure 3          TOD Impacts On Transport Activity in Portland, Oregon (Ohland and Poticha 2006)

People who live in transit-oriented developments drive less and rely more on alternative modes. “Daily VMT” indicates average daily vehicle miles traveled per capita.



By creating more dispersed Land Use patterns and reducing transportation Options, Automobile Dependency tends to significantly increase per capita vehicle travel and reduce use of alternative modes. For example, U.S. residents drive about twice as many annual miles as German residents of similar incomes living in communities with similar densities due to a combination of lower fuel prices and reduced transportation options (Buehler 2009) In Automobile dependent communities households use automobiles for most trips. In Transit Oriented communities they rely on a mix of modes. In Carfree communities, most trips are by non-motorized modes and public transit, automobile travel is reserved for work trips (such as delivery and service vehicles) and out-of-town travel, as illustrated in the table below.


Table 2            Typical Mode Share By Trip Purpose For Various Transport Systems

Trip Purpose

Automobile Dependent

Transit Oriented Development


Work commuting




School commuting




Work-related business




Personal travel (errands)




Social and recreation




Total car trips




Total transit trips




Total non-motorized trips




Total trips




Residents of automobile-dependent communities use automobiles for most trips. Transit oriented development results in the use of mixed modes. Carfree development results in minimal driving.




Benefits and Costs

This section describes various categories of costs and benefits caused by Automobile Dependency.



Increased Mobility

Automobile dependent transportation systems have high capacity roads and abundant parking, which maximizes automobile travel speed and convenience, and increases total personal mobility.


Affordable Vehicle Travel

Automobile Dependency is associated with minimal taxes on vehicle ownership and fuel, minimal tolls and parking fees, highly competitive markets for vehicles and vehicle services, making vehicle ownership relatively affordable even to lower-income households. Automobile Dependency tends to increase access to urban fringe land, increasing housing affordability, although this is partly offset by higher parking and public service costs (Land Use Evaluation).


Economic Development

Some businesses benefit from automobile dependency, including those involved in vehicle and fuel production, motor vehicle services, and automobile-dependent destinations (such as suburban housing and malls). However, as discussed later, this is offset by disbenefits to other businesses.




Transportation Expenditures

Although Automobile Dependency tends to minimize per-mile Vehicle Costs (fuel taxes, road tolls, parking fees, etc.), it tends to increase total vehicle costs by increasing per capita vehicle ownership and use. As a result, total transportation expenditures tend to increase with automobile dependency (Newman and Kenworthy, 1999, pp. 111-117; McCann, 2000; Litman, 2003, Table 13). McCann (2000) found that households in more automobile dependent communities devote more than 20% of household expenditures to surface transportation (over $8,500 annually), while those in communities with more diverse transportation systems spend less than 17% (under $5,500 annually). The cost to consumers is even greater because motor vehicle expenditures provide little long-term economic benefit: $10,000 spent on motor vehicles provides just $910 in equity, compared with $4,730 for the same investment in housing (McCann, 2000). This suggests that shifting consumer expenditures from motor vehicles to investments such as housing, education or savings can increase personal wealth.


Litman (2003) found that residents of the Smartest Growth U.S. cities spend 6% less of their income on combined transport, housing and food than residents of sprawled cities.


Consider another perspective. Table 3 compares the typical annual costs of a 10-mile urban-peak commute by different modes. It assumes that vanpool operating costs average 24˘ per mile, transit operating costs average $6.00 per bus-mile, and transit vehicles impose twice the roadway capacity and four times the external costs of an average automobile.


Table 3            Costs of Urban Commute (Transportation Costs)


Auto Costs











Vehicle Ownership






Vehicle Operation






Highway Capacity






























Alternative modes can provide significant annual savings over SOV commutes.



An average employee earns about $33,000 annually. Assuming that about half of urban automobile commutes could shift to more efficient alternative modes if given suitable incentives, the additional $6,000 in annual commuting costs associated with automobile-dependency, represents about a 10% surcharge on wages. Put another way, TDM programs can reduce urban employment costs by about 10% by providing commute cost savings. These various studies and perspectives indicate that Automobile Dependency reduces overall transportation Affordability.


Infrastructure Costs

By increasing per capita automobile ownership and use, Automobile Dependency increases costs for roads, Parking and traffic services by hundreds of dollars annually per capita (Transportation Costs). Many of these costs are borne indirectly through taxes, business overhead expenses, and housing costs.


Reduced Land Use Accessibility

Automobile Dependency creates less Accessible land use patterns, meaning that destinations are more dispersed, less mixed and less connected. This requires more mobility to maintain a given level of accessibility.


Reduced Transport Options – Inequity

If resources (money and space) were unlimited, and motor vehicle travel imposed no significant safety or pollution impacts on other modes of travel, and transportation policy decisions were always balanced, it might be possible for an automobile dependent community to maintain a good range of Transport Options. But these conditions do not exist. Transportation resources are limited, motor vehicle traffic degrades nonmotorized travel conditions (and therefore the feasibility of transit), and in automobile dependent communities, decision-makers tend to be less concerned with the needs of non-drivers. In practice, increased automobile dependency tends to reduce the quantity and quality of transportation alternatives.


The costs of automobile dependency consist, in part, of reduced benefits from a more diversified transport system. There are several specific benefits from transport diversity:


·         Solving Transportation Problems. Improved Transport Options is often the most cost effective way to address traffic congestion, facility costs, road risk, environmental impacts and consumer costs. Automobile dependency reduces the range of solutions that can be applied to such problems.


·         Consumers benefits. Improved options allows consumers to save money, avoid stress, and reduce their need to chauffeur non-drivers.


·         Efficiency. Consumer choice is necessary for economic efficiency (Market Principles). Improved transportation choice allows consumers to choose the most efficient option for each trip.


·         Equity. Inadequate transport options often limits the personal and economic opportunities available to people who are physically, economically or socially disadvantaged. Increasing transportation options can help achieve equity objectives.


·         Livability. Many people value living in or visiting a community where walking and cycling are safe, pleasant and common. There are also public Health benefits from increased walking and cycling. As a result, transportation options can help communities become more “livable,” resulting in increased property values and commercial activity.


·         Security and Resilience. Improved transportation options results in a more diverse and flexible transportation system that can accommodate variable and unpredictable conditions. Even people who do not currently use a particular form of transport may value its availability as a form of insurance to accommodate future needs.


The transport problems facing non-drivers in an automobile-dependent community can be defined in two different ways which suggest two different types of solutions. One defines the problem in terms of inadequate mobility, which suggests solutions such as making cars more affordable and subsidizing special bus services. The other approach defines the problems in terms of inadequate Accessibility, which suggest solutions that involve reducing the overall degree of Automobile Dependency and changing transport and land use policies. For example, to insure that students in transport disadvantaged households can get to school, officials can either fund special bus services (a mobility-oriented solution), or they can locate schools and manage road systems to insure that most students can easily walk to schools (an accessibility-oriented solution). Of course, most communities use a combination of both approaches, but some tend to emphasize one or another. In general, accessibility-oriented solutions tend to provide the broadest range of benefits to people who are transport disadvantaged.


Transportation System Cost Efficiency

Transit services and pedestrian facilities experience economies of scale: unit costs decline as the number of users increase, resulting in better facilities and services, and better integration with other components of the transportation system. More balanced transportation increases the efficiency of alternative modes.


Automobile dependent regions have lower transit system cost recovery (Newman and Kenworthy, 1999; Litman, 2004). Similarly, automobile dependency reduces the cost effectiveness of nonmotorized modes. Sidewalks and paths are not considered worthwhile investments in Automobile Dependent areas, because they receive little use. Communities must either provide less service or increase subsidies to maintain a given level of transportation options.


Traffic Crashes

Although Automobile Dependency includes vehicle and highway improvements that tend to reduce per-mile crash rates, they encourage more and faster driving, which increases total crashes (Evaluating Safety Impacts). This explains why per capita traffic deaths are far higher in sprawled communities, as illustrated in Figure 4.


Figure 4          Annual Traffic Death Rate (Ewing, Schieber and Zegeer, 2003)

The ten U.S. communities ranked least sprawled have much lower annual traffic fatality rates than the ten communities that are ranked most sprawled.



Health Impacts

Automobile-oriented transportation systems are associated with reduced exercise and unhealthy weight gains, and TDM strategies that increase walking and cycling can provide significant health benefits (Health Impacts). Many experts believe that increasing active transportation (walking, cycling, running and skating) is the most practical and effective way to improve public fitness. One major study concluded, “Regular walking and cycling are the only realistic way that the population as a whole can get the daily half hour of moderate exercise which is the minimum level needed to keep reasonably fit” (Physical Activity Task Force, 1995).



Automobile Dependent transportation and land use patterns result, in part, from efforts to reduce Traffic Congestion by continually increasing roadway system capacity and design speeds. However, this tends to be offset by increased per capita vehicle mileage and less Accessible land use. Although higher density areas with narrower streets and more balanced transportation sometimes have more intense congestion (as measured by roadway level of service or average traffic speeds), Automobile Dependency tends increase per capita congestion delay because people drive more vehicle miles (STPP, 1999; STPP, 2001; Litman, 2004).


Energy Consumption and Pollution Emission

By increasing per capita motor vehicle use, Automobile Dependency tends to increase per capita transportation energy consumption and pollution emissions (Energy and Emission Reductions). Although emission controls reduce per-mile emissions of most pollutants, in automobile dependent areas this is partly offset by increased vehicle mileage. As a result, per capita pollution emissions have decline less than what could otherwise be achieved, and energy consumption often increases.


Land Use Impacts

Automobile Dependency tends to cause a particular land use pattern often called sprawl: a relatively large portion of land devoted to roads and parking facilities, low-density, single-use, urban periphery development with dispersed destinations. Although there is considerable variation (not all automobile dependent communities have exactly the same land use patterns), Automobile Dependency encourages, and to some degree requires, such land use patterns.


This type of land use tends to reduce Accessibility, meaning that more travel is required to reach common services and activities. It also reduces Transportation Options, because such land use patterns are not conducive to walking or transit service.


These land use patterns impose a number of economic, social and environmental costs, as summarized in the table below.


Table 4          Costs of Sprawl (Evaluating Land Use Impacts)




·         Reduced accessibility and higher transportation costs.

·         Increased land devoted to roads and parking facilities.

·         Increased costs to provide public services.

·         Reduced regional business activity and employment.

·         Reduced economies of agglomeration.

·         Reduced economies of scale in transit and other alternative modes.

·         Threats to environmentally-sensitive businesses (e.g. farming and resorts).

·         Reduced accessibility for people who are transport disadvantaged.

·         Reduced housing options.

·         Increased external transportation costs (crash risk, pollution, etc.).

·         Degraded public realm.

·         Reduced neighborhood interaction and community cohesion.

·         Reduced opportunities to preserve cultural resources.

·         Reduced exercise by walking and cycling.

·         Increased impervious surface.

·         Reduced greenspace and habitat.

·         Increased energy consumption and pollution emissions.

·         Aesthetic degradation.

·         Increased water pollution.

·         Increased “heat island” effects.

This table summarizes various costs of sprawl, and costs that can be reduced by Smart Growth.



Economic Development

Since automobile use tends to increase with industrialization and personal incomes, many people assume that Automobile Dependency contributes to Economic Development. This is not true. Although motor vehicles used for industrial activities such as manufacturing and distribution can increase economic productivity, automobiles used for personal consumption, such as commuting or shopping that could be performed using other modes, contributes no economic benefit.


Although automobile dependency benefits some economic sectors, it burdens others. A dollar spent on automobiles means one less dollar for housing, food, entertainment, education, or investment. Expenditures on automobiles, fuel and roadway facilities provide relatively little regional economic activity because they are capital intensive and mostly imported from other regions.


During some historical periods automobile industries contributed significantly to regional economic development. For example, automobile manufacturing contributed to U.S. industrial development during the 1920s and 30s, and to economic redevelopment after WWII in Europe and Japan. Public policies that favored automobile ownership and use may have been justified when these industries were first developing and experienced economies of scale (you saved money if your neighbors increased their consumption of cars and fuel), but now that these industries are mature they tend to provide less employment and profit than other types of consumer expenditures.


Once a basic modern transportation system is established there is little evidence that increased automobile dependency contributes to economic development. On the contrary, there is evidence that beyond an optimal level (estimated to be about 7,500 per capita annual kilometers, although this varies depending on various geographic factors), increased automobile dependency reduces economic development by reducing transportation and land use efficiency, and increasing consumers consumption of imported goods (Litman and Laube, 1999).



Equity Impacts

Automobile Dependency has a variety of Equity impacts that are described below.


Horizontal Equity

Horizontal equity requires that public policies avoid arbitrarily favoring one individual or group. Automobile Dependency violates this principal by favoring motorists over non-motorists, and increasing the external costs imposed by motor vehicles. For example, Automobile Dependency requires that non-drivers pay for road capacity and parking facilities that they do not use, and as pedestrians, cyclists and transit riders bear greater congestion delays, crash risk and pollution from motor vehicle traffic. Although alternative modes (particularly transit) also impose significant external costs when measured per-mile, people who rely on these modes tend to travel less than people who are automobile dependent, and so tend to subsidize people who drive more than average (Transit Evaluation).


Vertical Equity with Respect to Income

This type of equity assumes that public policies should be progressive with respect to income, meaning that they should benefit people with lower incomes, or at least not harm them. Automobile dependency violates this principle. Lower income households devote a far greater portion of their wealth to transportation than higher income households, as indicated in Figure 5.


Figure 5          Transport Expenditures as Portion of Household Income (BLS, 1997)

Transportation expenditures are highest as a portion of income for lower-income households, indicating that automobile dependency is a financial burden to the poor.



Even an inexpensive car costs many hundreds of dollars a year to operate. Although an old car may be relatively inexpensive to purchase, it still has significant maintenance, repairs, insurance, fuel and residential parking costs. Higher income households can afford these costs (many spend considerably more on vehicles than necessary for extra comfort and Prestige features), but for lower-income households the additional transportation costs resulting from Automobile Dependency are a major burden. A Transportation Research Board (TRB, 2001) document states,


The burden of owning and operating vehicles is increasing for the lowest-income families.

Transportation was the third-highest household expense in the 1970s; today it is the second highest. For affluent households, this change reflects personal preferences. For families with lower incomes, however, particularly those living in automobile-dominated metropolitan areas, costs for transportation compete in magnitude with those for housing. In many low-income households in low-density suburbs, 25 percent of household income is spent on transportation.”



This is not to say that poor people don’t benefit from inexpensive driving (low priced fuel, subsidized parking, untolled roads). In the short term such underpricing can be progressive with respect to income. For example, free parking is a greater financial benefit to poor than wealthy motorists as a portion of income. Subsidies to driving may therefore be justified for the sake of vertical equity. But such practices are less equitable than flexible subsidies that can be used for other travel modes, since lower-income households tend to drive less than those with higher incomes. For example, Parking Cash Out tends to benefit low income people, many of whom already use alternative modes but currently receive no employee benefit comparable to parking subsidies provided to motorists. Similarly, low income people may benefit overall from road pricing if revenues are used, in part, to fund public transit or other transportation services used by low income people.


Vertical Equity with Respect to Need or Ability

This type of equity assumes that public policies should insure that people who are transportation disadvantaged due to physically disability or other special needs can achieve Basic Accessibility. Although some people with disabilities rely on automobile transportation, Automobile Dependency tends to be harmful to people who are transportation disadvantaged by reducing land use Accessibility and Transportation Options.



Optimal Level of Automobile Dependency

The optimal level of Automobile Dependency can be defined as the level that consumers choose in an efficient market in which they have viable transportation and land use choices, prices reflect full marginal costs, and public policies are neutral with respect to consumer’s transportation and location choices (Market Principles).


Excessive automobile dependency reduces economic efficiency in several ways. It reduces the range of solutions that can be used to solve specific transportation problems such as traffic congestion, road and parking facility costs, crashes and pollution. It increases transportation costs to consumers, businesses and governments. It forces people to drive even when they would prefer using alternatives, or when they are physically, mentally or emotionally unfit.


Current transportation and land use markets are distorted in several ways that encourage increased automobile ownership and use, create more automobile dependent land use patterns, and reduce transportation options. Some studies indicate that automobile use would decline by one-third to one-half in a more efficient market (Litman, 2001). To the degree that Automobile Dependency results from market distortions, it can be considered economically inefficient, inequitable and harmful to consumers overall.


Table 5          Market Distortions Contributing to Automobile Dependency (Market Principles)

Market Requirements

Current Transport Markets


Choice. Consumers need viable transportation and location choices, and information about those choices.

Consumers often have few viable alternatives to owning and driving an automobile, and living in automobile-dependent communities.

Increases automobile ownership and use beyond what would occur if consumers had better choices.

Competition. Producers must face competition to encourage innovation and efficient pricing.

Most roads and public transit services are provided as public monopolies. There is often little competition or incentive for innovation.

Reduces the diversity, efficiency and quality of non-automotive transportation options.

Cost-based pricing. Prices should reflect costs as much as possible, unless a subsidy is specifically justified.

Transportation in general, and driving in particular, is significantly underpriced. Many costs are either fixed or external.

Increases automobile ownership and use.

Economic neutrality. Public policies (laws, taxes, subsidies, and investment policies) should apply equally to comparable goods and users.

Tax policies, regulations and planning practices tend to favor automobile traffic over demand management alternatives.

Increases automobile ownership and use.

Land Use. Land use policies should not favor automobile oriented development.

Zoning laws, development practices and utility pricing tend to encourage lower-density, automobile-dependent land use patterns.

Increases urban sprawl, which increases automobile dependency and reduces transportation choice.

Current transportation systems often violate market principles. This increases automobile ownership and use, and urban sprawl development patterns, contributing to Automobile Dependency.



TDM and Smart Growth strategies can help correct these market distortions, creating a more balanced, economically efficient and equitable transportation system. TDM helps increase transportation choices, create efficient pricing and more neutral public transportation and land use policies. Most transportation and land use market reforms are considered TDM strategies.



Best Practices

Newman and Kenworthy (1999) and Holtzclaw (2000) recommend various strategies to reduce Automobile Dependency and create more efficient and Sustainable transportation systems. Some of these are summarized below.


·         Recognize the full economic, social and environmental impacts of automobile dependency in transportation and land use planning.


·         Recognize that individual transportation and land use decisions can have cumulative and synergistic impacts that contribute unintentionally toward automobile dependency. Establish policies to insure that individual decisions support long-term strategic objectives.


·         Recognize the potential economic, social and environmental benefits associated with a more diverse transportation system.


·         Establish community goals and objectives to increase transportation diversity and efficiency.


·         Implement Complete Streets Policies which ensure that roadway design and operating practices safely accommodate diverse users and activities including pedestrians, cyclists, motorists, public transport users, people with disabilities, plus adjacent businesses and residents. 


·         Create complete communities that contain residential, education, commercial, employment and recreational land uses. Include parks and other types of greenspace.


·         Create an integrated transportation system that provides a high level of accessibility for non-drivers. Provide safe, attractive transit and facilities for non-motorized transportation. Develop connections between walking, cycling, ridesharing, transit, taxis and other modes.


·         Require anybody involved in transportation and land use planning to spend at least two weeks each year without using a private automobile, in order to experience first hand the challenges facing non-drivers.


·         Implement TDM strategies to create a more balanced transportation system, and Smart Growth land use policies to create more accessible land use patterns.


·         Establish development policies that help create higher density, clustered, mixed land use patterns, with commercial activities in or near residential neighborhoods.


·         Reform planning policies and practices that limit density or result in excessive parking supply (more than consumers would choose if they were priced). Manage parking and minimize parking subsidies.


·         Use Least Cost planning practices, and road pricing to test motorists’ willingness to pay for roadway capacity expansion.



Highway System Inappropriate In Urban Areas


After the interstate-building program was well under way, the president also awoke to unexpected realities of the plan he had pushed.  On a summer day in 1959, Eisenhower's limousine was on its way to Camp David, Maryland, when the president noticed a huge earthen gash extending through the northwest section of the city.  Asking the reason for this massive intrusion of bulldozers he learned from an aide that this was his interstate highway system.  


Eisenhower recoiled in horror.  His interstate concept, borrowed from the German model, had been to go around cities, not through them.  Amazingly, he had been unaware during the lengthy congressional donnybrook that the only way the interstates could become a reality in this increasingly urban nation was to promise cities enough money to eviscerate themselves.  


The president immediately enlisted Bragdon and his staff to figure out how to stop the paving over of large sections of American cities.  But the BPR (Bureau of Public Roads) dug in its heels at every turn.  Nearing the end of his term, Eisenhower concluded that his hands were "virtually tied," and he reluctantly gave up, but not without reflecting on the wastefulness of thousands of motorists "driving into the central area and taking all the space required to park the cars."  In a few years his comments would prove prophetic.


Stephen Goddard (1994) Getting There: The Epic Struggle between Road and Rail in the American Century, Basic Books, p. 194.



Related Chapters

For more discussion of Automobile Dependency impacts see Smart Growth, Evaluating TDM, Measuring Transportation, Why TDM?, Comprehensive Transportation Planning, Market Principles, Evaluating TDM Equity, Comprehensive Transportation Planning, Resilience, Evaluating Land Use Impacts, Sustainable Transportation, Prioritizing Transportation and Transportation Options.



Wit and Humor

A guy walking along the street one night encounters a drunk on his hands and knees under a street light, searching the sidewalk. The guy asks the drunk what he was looking for, to which the drunk replies, “I’m looking for my car keys.” Being a helpful sort, the fellow starts searching too.


After about 10 futile minutes crawling on his hands and knees the fellow asked, “Are you sure you lost them here?”


“No, I lost them down the street,” replied the drunk, “but its easier to see under this streetlight.”



Examples and Case Studies


Fairness in a Car Dependent Society (

The U.K. Sustainable Development Commission (SDC 2011) commissioned a study that analyzes the costs of car dependency and ways to ensure that the decisions we make about future transport priorities help minimise the negative impacts on everyone. It concludes that a new approach to national transport policy is needed which achieves a better balance between potentially conflicting rights and freedoms in a way that is equitable for both this and future generations and, which respects environmental limits. This approach must recognise that transport planning decisions have significant indirect and external impacts, and so should consider effects on all members of society, not just motorists.



References And Resources For More Information


John Adams (1999), The Social Implications of Hypermobility, Report for OECD Project on Environmentally Sustainable Transport, Organization for Economic Cooperation and Development (; summary at


PBQD (1998), Consequences of the Interstate Highway System for Transit, Transit Cooperative Research Program Report 42, Transportation Research Board (


Jeffrey R. Brown, Eric A. Morris and Brian D. Taylor (2009), “Paved With Good Intentions: Fiscal Politics, Freeways, and the 20th Century American City,” Access 35 (, Fall 2009, pp. 30-37; at


Ralph Buehler (2009), “Determinants of Automobile Use: Comparison of Germany and the United States,” Transportation Research Record 2139, TRB (, pp. 161-171; at


Robert Burchell, et al (1998), The Costs of Sprawl – Revisited, TCRP Report 39, Transportation Research Board (


Daniel Carlson, Lisa Wormser, and Cy Ulberg (1995), At Road’s End; Transportation and Land Use Choices for Communities, Island Press (


Complete Streets ( is a campaign to promote roadway designs that effectively accommodate multiple modes and support local planning objectives.


Patrick Condon (2004), Canadian Cities American Cities: Our Differences Are The Same, University of British Columbia, Funders Network for Smart Growth (


Jim Conley and Arlene Tigar McLaren (2009), Car Troubles: Critical Studies of Automobility and Auto-Mobility, Ashgate (; at


Jago Dodson and Neil Sipe (2006), Shocking the Suburbs: Urban Location, Housing Debt and Oil Vulnerability in the Australian City, Research Paper 8, Urban Research Program, Griffith University (; at


Reid Ewing, Rolf Pendall and Don Chen (2002), Measuring Sprawl and Its Impacts, Smart Growth America (


Reid Ewing and Shima Hamidi (2014), Measuring Urban Sprawl and Validating Sprawl Measures, Metropolitan Research Center at the University of Utah for the National Cancer Institute, the Brookings Institution and Smart Growth America (; at


Nicole Foletta and Simon Field (2011), Europe’s Vibrant New Low Car(bon) Communities, Institute for Transportation and Development Policy (; at


David J. Forkenbrock and Glen E. Weisbrod (2001), Guidebook for Assessing the Social and Economic Effects of Transportation Projects, NCHRP Report 456, Transportation Research Board, National Academy Press (


Timothy Garceau, et al. (2013), “Evaluating Selected Costs Of Automobile-Oriented Transportation Systems From A Sustainability Perspective,” Research in Transportation Business & Management, Vol. 7, July 2013, pp. 43-53;


Aaron Golub (2007), Explaining Automobile Dependence in the United States: Financial and Industrial Concentration and Demand Management, 11th World Conference on Transport Research, Berkeley, California (


John W. Holtzclaw (2000), Smart Growth – As Seen From The Air: Convenient Neighborhood, Skip The Car, Presented at the Air & Waste Management Association’s 93rd Annual Meeting; available at the Sierra Club Stop Sprawl website (


ITDP (2012), Transforming Urban Mobility In Mexico: Towards Accessible Cities Less Reliant on Cars, Institute for Transportation and Development Policy (; at


Santhosh Kodukula (2011), Raising Automobile Dependency: How to Break the Trend?, GIZ Sustainable Urban Transport Project (; at


Jonathan Levine (2006), Zoned Out: Regulation, Markets, and Choices in Transportation and Metropolitan Land-Use, Resources for the Future (


Todd Litman (2001), The Costs of Automobile Dependency and the Benefits of Transportation Diversity, Victoria Transport Policy Institute (


Todd Litman (2003), Evaluating Criticism of Smart Growths, VTPI (; at


Todd Litman (2004), Comprehensive Evaluation of Rail Transit Benefits, VTPI ( ; at


Todd Litman (2005), Socially Optimal Transport Prices and Markets, VTPI (; at


Todd Litman (2001), “You Can Get There From Here: Evaluating Transportation Choice,” Transportation Research Record 1756, Transportation Research Board (, pp. 32-41; at


Todd Litman (2006), “Transportation Market Distortions,” Berkeley Planning Journal; issue theme Sustainable Transport in the United States: From Rhetoric to Reality? (, Volume 19, pp. 19-36; at


Todd Litman (2006b), Understanding Smart Growth Savings: What We Know About Public Infrastructure and Service Cost Savings, And How They are Misrepresented By Critics, Victoria Transport Policy Institute (; at


Todd Litman (2007), Evaluating Transportation Land Use Impacts, Victoria Transport Policy Institute (; at


Todd Litman (2007), Community Cohesion As A Transport Planning Objective, Victoria Transport Policy Institute (; at


Todd Litman (2007), Pavement Buster’s Guide: Why and How to Reduce the Amount of Land Paved for Roads and Parking Facilities, VTPI (; at


Todd Litman (2008), Land Use Impacts On Transport: How Land Use Factors Affect Travel Behavior, VTPI (; at


Todd Litman (2009), Transportation Cost and Benefit Analysis: Techniques, Estimates and Implications, Victoria Transport Policy Institute (


Todd Litman (2009), Where We Want To Be: Household Location Preferences And Their Implications For Smart Growth, VTPI (; at


Todd Litman (2011), The First Casualty of a Non-Existent War: Evaluating Claims of Unjustified Restrictions on Automobile Use, and a Critique of 'Washingtons War On Cars And The Suburbs', Victoria Transport Policy Institute (; at


Todd Litman (2013), “The New Transportation Planning Paradigm,” ITE Journal (, Vo. 83, No. 6, pp. 20-28; at


Todd Litman and Marc Brenman (2011), “Bias Begets Dependency: Conventional Planning Favors Automobile Travel,” Canadian Property Management (, July-August, pp. 30-32; based on, A New Social Equity Agenda For Sustainable Transportation, Paper 12-3916, Transportation Research Board Annual Meeting (; at


Todd Litman and Felix Laube (1998), Automobile Dependency and Economic Development, VTPI (; at


Karen Lucas and Peter Jones (2009), The Car in British Society, RAC Foundation (; at


William Lucy (2002), Danger in Exurbia: Outer Suburbs More Dangerous Than Cities, University of Virginia (, 2002; summarized in


Barbara McCann (2000), Driven to Spend; The Impact of Sprawl on Household Transportation Expenses, STPP (


Peter Newman and Jeff Kenworthy (1989), Cities and Automobile Dependency, Gower.


Peter Newman and Jeffrey Kenworthy (1999), Sustainability and Cities; Overcoming Automobile Dependency, Island Press (


OECD (2001), International Road Traffic and Accident Database, Organization for Economic Cooperation and Development (


Gloria Ohland and Shelley Poticha (2006), Street Smart: Streetcars and Cities in the Twenty-First Century, Reconnecting America (


Physical Activity Task Force (1995), More People, More Active, More Often, UK Department of Health (London).


John Pucher and Christian Lefevre (1996), The Urban Transportation Crisis in Europe and North America, MacMillan Press (London).


Peter Samuel and Todd Litman (2001), “Optimal Level of Automobile Dependency; A TQ Point/Counterpoint Exchange with Peter Samuel and Todd Litman,” Transportation Quarterly, Vol. 55, No. 1, Winter 2000, pp. 5-32; at


SDC (2011), Fairness in a Car Dependent Society, U.K. Sustainable Development Commission (; at


Scott Sharpe and Paul Tranter (2010), “The Hope For Oil Crisis: Children, Oil Vulnerability And (In)Dependent Mobility,” Australian Planner, Vol. 47, No. 4, December, pp. 284-292; summary at


Dennis Soron (2009), “Driven To Drive: Cars And The Problem Of 'Compulsory Consumption',” Car Troubles: Critical Studies of Automobility and Auto-Mobility (Jim Conley and Arlene Tigar McLaren eds), Ashgate (, pp. 181-196;


STPP (2001), Easing the Burden: A Companion Analysis of the Texas Transportation Institute's Congestion Study, Surface Transportation Policy Project (


D. Talukadar (1999), “Economic Growth and Automobile Dependence,” Thesis, MIT, 1997, cited in Ralph Gakenheimer, “Urban Mobility in the Developing World,” Transport. Research A, Vo. 33, 1999, p. 680.


Transportation for Livable Communities ( is a resource for people working to create more livable communities by improving transportation.


Martin Turcotte (2008), “Dependence on Cars in Urban Neighbourhoods: Life in Metropolitan Areas,” Canadian Social Trends, Statistics Canada (; at


John Urry (2004), “The System of ‘automobility,” Theory, Culture and Society, Vol. 21, Issue 4/5, pp. 25–39; at


Lucie Valličres (2006), Disciplining Pedestrians? A Critical Analysis Of Traffic Safety Discourses, Simon Fraser University; at


Ming Zhang (2005), “Intercity Variations In The Relationship Between Urban Form And Automobile Dependence: Disaggregate Analyses Of Boston, Portland, And Houston,” Transportation Research Record 1902, TRB (, pp. 55-62.


Ming Zhang (2006), “Travel Choice with No Alternative: Can Land Use Reduce Automobile Dependence?” Journal of Planning Education and Research, Vol. 25, No. 3, pp. 311-326;

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