Sprawl and Health

Crane 1998 - "Does Neighborhood Design Influence Travel?: A Behavioral Analysis of Travel Diary and GIS Data"

Randall Crane and Richard Crepeau
"Does Neighborhood Design Influence Travel?: A Behavioral Analysis of Travel Diary and GIS Data"
Transportation Research Part D: Transport and Environment
3(4):225-238 (July 1998)
On the Web

 

From the abstract:
An analysis of household travel diary and GIS data for San Diego finds little role for land use in explaining travel behavior, and no evidence that the street network pattern affects either short or long non-work travel decisions. While results may vary in other areas, the empirical argument for using land use as an element of regional air quality or other environmental plans remains to be demonstrated.

(I didn't read the study intensively enough to comment, but see Cervero and Gorham (1995) for another study on Southern California.)

 

Cervero 1995 - "Commuting in Transit Versus Automobile Neighborhoods"

Robert Cervero and Roger Gorham
"Commuting in Transit Versus Automobile Neighborhoods"
Journal of the American Planning Association
61(2):210-225 (Spring 1995)

From the abstract:
This article compares commuting characteristics of transit-oriented and auto-oriented suburban neighborhoods in the San Francisco Bay Area and in Southern California. Transit neighborhoods averaged higher densities and had more gridded street patterns compared to their nearby counterparts with auto-oriented physical designs. . . For both metropolitan areas, pedestrian modal shares and trip generation rates tended to be considerably higher in transit than in auto-oriented neighborhoods. Transit neighborhoods had decidedly higher rates of bus commuting only in the Bay Area. Islands of transit-oriented neighborhoods in a sea of freeway -oriented suburbs seem to have negligible effects on transit commuting.

Frank 2006 - "Many Pathways from Land Use to Health"

Lawrence D. Frank, James F. Sallis, et al.
"Many Pathways from Land Use to Health"
Journal of the American Planning Association
72(1):75-87 (Winter 2006)
On the Web
Relevance: high

From the abstract: in King County neighborhoods and found that a 5% increase in walkability was associated with:

• a per capita 32.1% increase in time spent in physical activity
• 0.23 point reduction in average body mass index
• 6.5% fewer vehicle miles traveled
• 5.6% fewer grams of nitrogen oxides emitted
• 5.5% fewer grams of volatile organic compounds emitted

See study for more details.

Handy 2005 - "Correlation or Causality Between the Built Environment and Travel Behavior? Evidence from Northern California"

Handy, Susan; Cao, Xinyu; Mokhtarian, Patricia
"Correlation or Causality Between the Built Environment and Travel Behavior? Evidence from Northern California"
Transportation Research Part D
November 2005; v.10, n.6; pp.427-444
On the Web
Relevance: medium

Handy et al surveyed residents of traditional and suburban neighborhoods on their travel habits, travel attitudes, perceived neighborhood attributes, and socio-economic status. They found that while residents of traditional neighborhoods drove 18% fewer miles than suburban residents, the variation in this cross-section could be better explained by differences in attitudes and SES factors than in the built environment.

When the authors separated out those who had moved in the past year for a quasi-longitudinal study, differences in the built environment (mainly in accessibility) appeared significant. The built environment seemed to affect increased walking more than decreased driving.

I'm a bit wary of the quasi-longitudinal part of this study. Why would the built environment be significant there but not in the cross-sectional analysis?

Lund 2002 - "Pedstrian Environments and Sense of Community"

Lund, Hollie
"Pedestrian Environments and Sense of Community"
Journal of Planning Education and Research   
2002 Associate of Collegiate Schools of Planning
On the Web
Relevance: medium-high

Lund's study is intended to gauge the community effects of New Urbanism-style architecture and neighborhood design. The study is conducted in two Portland neighborhoods, an inner-city neighborhood with traditional design and a modern-style suburban neighborhood (post-WWII). Researchers distributed questionaires door-to-door in the two neighborhoods using questions similar to the Nasar study. They got 57 responses (22 percent) in the traditional neighborhood and 49 (18.8 percent) in the suburban neighborhood.

The study found more sense of community in the traditional neighborhood than in the modern suburb. The most powerful subjective explanatory variable was "perception of walking"--the better that people felt about walking in the neighborhood, the higher their sense of community. Interestingly, there is one big counterpoint to this: the study found a negative correlation between destination trips (walking to the store or for other errands) and sense of community. That is, the more likely people are to walk to destinations, the lower their sense of community. Strolling trips--walking for pleasure--are positively associated with community, but destination trips are negatively associated.

One failing of this research is that the respondents are self-selected and many not be statistically accurate representations of their communities. Also, the number of respondents is relatively low and it may be difficult to obtain statistically valid results when using controls or regressions. Finally, we cannot be sure whether people's behavior and attitudes are determined by their urban environment, or whether people self-select into neighborhoods that reflect their values and preferences.

Kingham 1998 - "Assessment of Exposure to Traffic-Related Fumes During the Journey to Work"

Kingham, Simon; Meaton, Julia; et al.
"Assessment of Exposure to Traffic-Related Fumes During the Journey to Work"
Transportation Research, Part D
July 1998; v.3, n.4; pp.271-274
On the Web
Relevance: medium-low

In a pilot study, the authors measured commuter's exposure to benzene and particulates using different modes (car, bus, train, road cyclist, path cyclist) but along similar routes(?). Findings include:

• The car driver had the highest mean exposure to benzene (108.3 micrograms/m^3) a factor of at least 4 and also the highest mean exposure to particulates (7.6 absorbance), but by a much smaller margin.
• Train riders had the lowest benzene exposure (12.9) and path cyclists had the lowest particulate exposure (2.7).
• The bus was slightly better than the road bike
• The exposure ratios for the car driver to the road cyclist were 4.05 for benzene and 1.26 for particulates.
• The exposure ratios for the road cyclist to the path cyclist were 1.73 for benzene and 2.41 for particulates.

Adams 2002 - "Assessment of Road Users' Elemental Carbon Personal Exposure Levels, London, UK"

Adams, HS; Nieuwenhuijsen, MJ; Colvile, RN.
"Assessment of Road Users' Elemental Carbon Personal Exposure Levels, London, UK"
Atmospheric Environment
November 2002; v.36, n.34; pp.5335-5342
On the Web
Relevance: low

The authors measured exposure to elemental carbon (EC) a component of diesel exhaust, along various routes, using different modes, and in summer vs. winter.  They found that exposure levels were higher:

• for cars, followed by buses and bicycles (cyclists may have lower exposure because they don't get stuck in traffic and keep "away from the central road 'tunnel of pollution'.";
• along the most congested central route, perhaps due to higher traffic density and a street canyon effect;
• in winter, perhaps due to colder engines and more stable meteorological conditions.

Adams 2001 - "Determinants of Fine Particle (PM2.5) Personal Exposure Levels in Transport Microenvironments, London, UK"

Adams, HS; Nieuwenhuijsen, MJ; Colvile, RN
"Determinants of Fine Particle (PM2.5) Personal Exposure Levels in Transport Microenvironments, London, UK"
Atmospheric Environment
September 2001 v.35, n.27; pp.4557-4566
On the Web
Relevance: medium-low

The authors measured concentrations of fine PM on fixed routes using different modes (car, bus, bicycle) in London. They found that route was a significant factor, explaining 20% of the variation, but mode was not. Wind speed explained 18% of the variation. "Personal exposure levels were reasonable correlated with urban background FSM [fixed site monitor] concentrations."

Ewing 2002 - "Measuring Sprawl and Its Impact"

Ewing, Reid; Pendall, Rolf; Chen, Don
"Measuring Sprawl and Its Impact"
Smart Growth America
2002
On the Web
Relevance: high

Ewing et al. created a sprawl index for ~83 metropolitan areas, incorporating density, land use mix, centeredness, and street accessibility. The authors also estimated the impact of sprawl on various transportation-related outcomes. They found that a higher degree of sprawl is associated with higher average vehicle ownership, daily VMT per capita, annual traffic fatality rate, and maximum ozone level; more sprawl was associated with a lower share of work trips by transit and walking. Note that, as with most sprawl studies, we can't assume a causal relationship.

Kelly-Schwartz 2004 - "Is Sprawl Unhealthy?"

Kelly-Schwartz, Alexia; Stockard, Jean, et al
"Is Sprawl Unhealthy? A Multilevel Analysis of the Relationship of Metropolitan Sprawl to the Health of Individuals"
Journal of Planning Education and Research
December 2004; v.24, n2; pp.184-196
On the Web
Relevance: high

The authors replicated and extended Ewing et al's work on the effect of sprawl on health. They compared self- and physican-rated health as well as a variety of chronic conditions across metropolitan areas while controlling for income, education, sex, etc. They found that sprawl does affect health somewhat, but in a complex way that is difficult to track.  It appears that a highly gridded street network is associated with better health while more density is associated with poorer health.  While sprawl was not significantly associated with a higher prevalence of chronic conditions, among those with those conditions, the gridded street network was associated with better health.