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Subjects › Transportation › Transportation Efficient Land Use: Planning and Land Use Strategies that Reduce the Need to Drive
Updated 11/2012

Transportation Efficient Land Use:
Planning and Land Use Strategies that Reduce the Need to Drive

Contents

Introduction

This webpage highlights a number of land use and community design strategies that can reduce the need for travel or the distance that must be traveled. It presents ideas about community design and land use patterns that allow greater choice in travel mode, or otherwise reduce the need to drive alone.

Development patterns and community design characteristics significantly influence the distance and manner that people travel. In recent decades, the increase in spread out development patterns means that people spend more time on the road to get to jobs, services and their homes. When residential, commercial, employment and other uses are separated by significant distances, more of the trips and errands will be made by automobile, as walking, cycling and public transit become less practical. (According to the Victoria Transport Institute, most people rely on commercial and public services they can reach within 10 minutes, and try to choose jobs that they can reach within a 40-minute commute.) Carpooling may also become more difficult, when job locations are more spread out, rather than focused in a central city. In addition, low-density, sprawling development does not provide enough potential riders to support frequent and convenient transit service. As we spend more time in our cars, roads become more congested, energy resources are consumed, and vehicle emissions are increased. Studies documenting these land use/transportation relationships have generated renewed interest in a better integration of land use planning and transportation planning as one important way to reduce traffic congestion, energy use, and vehicle emissions, while improving walkability and public health.

General Information - Land Use/Transportation Coordination

Washington Studies and Information

Other General Information and Guidance

Compact Development/Transportation-Efficient Density

Compact, higher density development patterns shorten the distance people must travel to reach work, shopping, or other points of interest. Compact development allows people to conveniently walk or cycle to some destinations within a reasonable time. Higher densities also supply the potential ridership that can support more frequent transit service and a greater variety of routes. The result is more transportation options, less time on the road, and reduced traffic congestion. At the same time, well-designed compact development contributes to vibrant, economically healthy neighborhoods and to centers that offer a variety of goods and services, social gathering places, recreation/entertainment opportunities and attractive character.

Many local jurisdictions in Washington (and in other states) are using a variety of tools to discourage sprawling development and to promote higher densities within target growth areas. Approaches include higher density concentrated in accessible nodes or centers, mixed-use development that permits residences within walking distance of commercial services and other attractions, infill development that provides additional close-in housing, density bonuses in exchange for amenities, minimum density requirements, allowances for accessory dwelling units, and transfer of development rights programs. In addition, many communities are permitting and establishing guidelines for a variety of mid-range density housing such as cottage housing, corner lot duplexes, townhouses or garden apartments that fit more easily into or adjacent to established residential neighborhoods.

Recent studies and reports, such as those listed below, have provided considerable clarification about the role of density, quick access to jobs and other factors in reducing vehicle travel, energy use, and greenhouse gases.

Major Recent Studies and Commentary

  • Draft Policy Brief on the Impacts of Residential Density Based on a Review of the Empirical Literature (Adobe Acrobat Document), Marlin G. Boarnet, University of California, Irvine, and Susan Handy, University of California, Davis, June 25, 2010 - This policy brief is a good place to start. It sheds light on variable study results and summarizes results of several better designed studies about the role of density in reducing VMT and greenhouse gases. It is also helpful in understanding some basic concepts and caveats related to density. Among the results: increased density is more likely to have a significant effect in places where there is unmet demand for higher density housing, and when it is combined with other more important land use factors, such as locations with quick access to employment centers.
  • Driving and the Built Environment: The Effects of Compact Development on Motorized Travel, Energy Use, and CO2 Emissions, Transportation Research Board Special Report 298, National Research Council, 09/2009 - This report examines the relationship between land development patterns and vehicle miles traveled (VMT) and the extent to which an increase in compact, higher density, mixed use development could reduce VMT and greenhouse gases (GHG). The literature review suggests that doubling residential density across a metropolitan area may reduce VMT by 5 to 12%, and perhaps as much as 25% if coupled with higher employment densities, mixed uses, and transit improvements. The report recommends encouraging more compact, mixed use development, but estimated that the likely increase in such development would only reduce VMT, energy use, and GHG by about 1% to 11% by the year 2050.
  • Land Use and Driving: The Role Compact Development Can Play in Reducing Greenhouse Gas Emissions, Urban Land Institute, 2010 - Clearly written report summarizes results from three recent studies that estimate reductions in VMT and energy consumption of between 8 and 18 percent when compact development makes up 60 percent or more of all future development between now and 2050. Also reports on study models that predict which strategies promote the greatest VMT and GHG reduction.
  • Transit and the “D” Word, Robert Cervero and Erick Guerra, Access, University of California Transportation Center (UCTC) Spring 2012 – Summary of research from 2010 and 2011 studies which look at capital costs per mile and per rider for transit system investments and necessary density for cost-effectiveness. Contains useful summary tables. Links to two studies are below:
    • Urban Densities and Transit: A Multi-dimensional Perspective (Adobe Acrobat Document), Robert Cervero and Erick Guerra, Institute of Transportation Studies, University of California, Berkeley, Working Paper, 09/2011 - Analysis suggests that light-rail systems need around 30 people per gross acre within a half mile of stations and heavy rail systems need 45 people per gross acre within the 1/2 mile radius to place them in the top one-quarter of cost-effective rail investments in the U.S top performing transit systems). However such densities arelikely politically unacceptable in smaller communities.
    • Costs of a Ride: The Effects of Densities on Fixed-Guideway Transit Ridership and Capital Costs (Adobe Acrobat Document), Robert Cervero and Erick Guerra, University of California, Berkeley, 08/2010 - In addition to information on rail densities and costs, see Table 1, page 3 for summary of transit-supportive density levels adapted from Pushkarev and Zupan (1977) for bus service. Minimum residential densities per net acre within the transit corridor for local bus service range from four units per acre for 20 bus/day, seven units per acre for 40 bus/day, and 15 units per acre for 120 bus/day service.
  • Travel and the Built Environment: A Meta-Analysis, Reid Ewing and Robert Cervero, Journal of the American Planning Association, Volume 76, Issue 3, 2010 - Draws on more than 60 studies to evaluate to what degree various land use patterns contribute to reduced car travel. The most effective way to minimize driving is to locate development in existing centers, (especially near the core of a metropolitan area) that are within easy driving distance of many jobs, shopping, and other attractions. A mix of uses and street network design are of secondary importance, and both are more important than just bumping up density. However, the combined effect of several such variables on travel could be quite large. Walking is most strongly related to land use diversity, intersection density, and the number of destinations within walking distance. Proximity to transit and street network design and to a lesser degree, mix of uses, are most related to increased bus and train use.

Other Density Information

Related MRSC Pages

Transportation-Efficient Site Design

In recent decades, site design of development has tended to focus on efficient vehicle circulation while neglecting pedestrian, bicycle and transit circulation. Well-conceived site design can minimize travel distances and times for pedestrian, bicycle or transit trips. A continuous network of streets and sidewalks providing direct connections between destinations, and short blocks allowing more frequent street crossing to destinations, will minimize walking or cycling distances. In addition, measures that create a safe, comfortable, convenient environment will encourage pedestrian, bicycle and transit travel. Examples of measures include weather protection, lighting, separation from vehicle traffic, bus shelters and seating, bicycle racks, changing rooms, attractive streetscape, and similar measures.

Recent studies indicate that improved design of pedestrian, bicycle and transit facilities can result in a substantial increase in the number of people who choose to walk, bike or ride transit. For instance, a recent University of Washington study found three times the pedestrian volumes in areas with short blocks and continuous and direct sidewalk connections compared to areas that lacked such systems. Similarly, a study in the Portland area concluded that vehicle miles traveled could by reduced by 10% in the suburbs by creating a pedestrian-oriented environment similar to that found in older Portland neighborhoods.

Street Connectivity

A well-connected street (and sidewalk) network reduces the distances that must be traveled between destinations and offers more route choices. In such a system, blocks are small, streets are provided at more frequent intervals, and there are minimal dead ends (cul-de-sacs). A major benefit of good street connectivity is decreased traffic on arterials because there are more alternative routes. A well-connected system also provides continuous, direct routes that facilitate walking or cycling to destinations, including transit stops. Emergency response time is also improved. Neighborhood residents and developers may resist a "grid" street system when they fear increased traffic through neighborhoods or increased expenses related to more frequent street intervals. However, street design that utilizes narrow streets, traffic calming devices and other design features can address many of these issues.

Code Examples

School Siting and Transportation

Traditionally, schools occupied a central place within compact neighborhoods and community centers. Many students could conveniently walk or bike to school. In recent decades, there has been a trend toward building ever larger schools on large sites in low density areas remote from existing population centers.

Several studies document the transportation implications of these trends. According the 2001 National Household Travel Survey (NHTS), less than 15 percent of students between the ages of five and 15 walked to or from school, and 1 percent biked. A comparable 1969 survey found that 48 percent of students walked or biked to school. Long travel distances are the major barrier. Other studies indicate that even children living close to schools are significantly less likely to walk. A poor walking environment, often associated with sprawl, also discourages walking and cycling. The magnitude of school siting impacts on the transportation network is considerable. For instance, a recently-built school in one southern city that will accommodate 2600 students will generate approximately 6000 vehicle trips per day. School siting policies have major impacts on public budgets. The Maine State Planning Office has found that although student enrollment dropped by 27,000 between 1970 and 1995, school busing costs rose from $8.7 million to over $54 million during that same period - again associated with changing land use patterns.

Studies have also linked childhood obesity, reduced opportunity to participate in extra-curricular activities, and a higher level of student anonymity and social alienation to the large school/distant location trend.

Background Information, Articles, Studies on School Siting

Local and State Government School Siting Policies

Siting Policies for Other Government Offices and Institutions

Many government agencies, and institutions, such as government offices, courthouses, post offices, and museums attract significant numbers of customers, visitors and employees. They can be major generators of traffic and parking demand. Such agencies often serve senior citizens, children, handicapped individuals and others who do not have automobiles, or who choose not to drive. Washington's Commute Trip Reduction Plan encourages such agencies and institutions to locate within high-density areas, central business districts, or other activity centers that offer regular transit service and pedestrian and bicycle facilities. Clustering such uses together within community centers can help minimize new vehicle trips and parking demand, and can make combined trips possible. In addition, strategic location of agencies and institutions that attract visitors can contribute to downtown revitalization efforts and increased vitality of community centers.

Incentive Programs to Encourage Close-in Living

Some communities are experimenting with different types of financial incentives that encourage homebuyers or developers to choose transportation efficient locations. Transportation efficient locations are areas that have good transit service, good walking and cycling conditions, and minimal commuting distances. Residents in these areas potentially have reduced transportations costs and more money available for housing or other needs. Location-efficient development also benefits local governments when the costs of providing public facilities and services can be minimized.

  • Center for Neighborhood Technology presentation (Adobe Acrobat Document) to Home Depot Foundation National Partners and Federal Government Officials by Scott Bernstein, President, Washington D.C., January 27, 2010 - Makes the case for considering the combined cost of housing and transportation when calculating housing affordability. Provides supporting data and rationale for the location‐efficient mortgage program, while noting that the Fannie Mae program is currently dormant
  • Florida Transportation Mobility Fee Study (Adobe Acrobat Document), Florida Department of Community Affairs, March 25, 2009 - Describes fee approaches that consider vehicle miles traveled as a factor in amount of fee paid
  • H + T Affordability Index - An innovative tool that challenges the traditional measure of affordability used by planners, lenders, and most consumers, which recommends that housing should be less than 30 percent of income. The H + T Index, in contrast, takes into account not just the cost of housing, but the costs of housing and transportation
  • Lancaster, CA Distance-Based Impact Fees, The New Rules Project - Impact fee model includes a surcharge levied on new development beyond the central core - the farther out, the higher the charge
  • Location Efficient Development and Mortgages, TDM Encyclopedia, Victoria Transport Policy Institute - Lenders use a model to determine which locations have lower transportation costs, allowing applicants to qualify for higher loan amounts, updated 12/13/2010
  • Pay-As-You-Drive Vehicle Insurance, TDM Encyclopedia, Victoria Transport Policy Institute - Insurance premiums based on how much the policyholder drives the vehicle during the policy period (the more you drive, the more you pay), updated 09/01/2011
  • San Mateo's TOD Incentive Program - Regional agency rewards constituent cities for building units near transit stations. Winner of U.S. Environmental Protection Agency National Award for Smart Growth Achievement, 2002
  • Incentives to Facilitate Infill Development, MRSC

Need more information?

Feel free to Ask MRSC. Washington cities, counties, and our contract partners can call or email MRSC for more information and advice - free of charge.