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Dumbaugh 2005 - "Safe Streets, Livable Streets"

Dumbaugh, Eric
"Safe Streets, Livable Streets"
Journal of the American Planning Association
Summer 2001; vol.71, n.3; pp.283-300
On the Web
Relevance: low

While conventional wisdom recommends limiting roadside hazards, such as trees, and increasing lane and shoulder width will reduce the number and severity of crashes where the driver leaves the roadway, this author posits that trees and narrow lanes encourage drivers to drive more slowly and carefully, reducing the total number of crashes.

The author cites a few studies, including on in Washington on an urban/rural arterial (HWY 99?), where the presence of trees, sign supports, and other fixed objects is associated with fewer total crashes while wider lanes and shoulders are associated with more crashes. The author then conducts his own study comparing different sections of the same roadway, finding similar results.

I'd say that the numerical results in this study are a little squishy, the they and the theory are nonetheless very compelling.


Washington Dept. of Ecology 2004 - "The Economic Benefits of Clean Air

Washington Dept. of Ecology
"The Economic Benefits of Clean Air"
Created Sept 2002, updated June 2004
Publication number 02-02-011
On the Web
Relevance: medium

The Washington State Department of Ecology says that

  • “Washington citizens save over $2 billion per year in health costs because the air is cleaner now than it was in 1990.”
  • “Washington businesses save at least $17 million per year because cleaner air means fewer lost workdays or lost productivity due to illness caused by air pollution, according to EPA.”
  • “Based on EPA estimates of cancer risks and measured pollution levels in Washington, [levels] of 11 high risk Hazardous Air Pollutants (HAPs) […] may result in as many as 30 cancer cased per year in Washington that would not otherwise have occurred. The cost of medical treatment alone for these is about $3,000,000.” 

It also estimates that if central Puget Sound and Clark county returned to ozone non-attainment, it would cost businesses $253 million for required cleaner gasoline and additional pollution controls.  In central Puget Sound it would also cost consumers about $10 million a year (1 penny per gallon) for required cleaner gasoline. In addition, we would lose local control over clean air strategies.

(Note that these estimates cover all air pollution, including industrial emissions and agricultural burning.)


Brauer 2000 - "Evaluation of Ambient Air Pollution in the Lower Mainland of British Columbia"

Brauer, Michael; Brumm, Jochen; Ebelt, Stefanie
"Evaluation of Ambient Air Pollution in the Lower Mainland of British Columbia: Public Health Impacts, Spatial Variability, and Temporal Patterns"
Submitted to the Administrative Council of Lower Mainland Medical Health Officers
On the Web
Relevance: high

This study estimates that 0 to 600 excess deaths annually in the BC Lower Mainland each year can be attributed to anthropogenic outdoor air pollution. However, most of these deaths are for individuals age 65 and older and associated with cardiovascular disease.

This study modeled where certain air pollutants are concentrated, finding that Vancouver's air is not always dirtiest: "CO and NO2 concentrations were higher in Vancouver relative to locations in the eastern part of the region. In contrast, O3 concentrations were significantly higher in the Fraser Valley relative to Vancouver/Burnaby. PM10 did not exhibit much spatial variability, with concentrations being relatively homogeneously distributed within the region." See maps in the study.

The study also compared Vancouver's average concentrations to other cities including Seattle and Portland. For annual averages, Vancouver ranks best on PM10, CO, and ozone, while Seattle and Portland rank better on NO2.


BC Lung Assoc 2005 - "Health and Air Quality 2005 - Phase 2: Valuation of Health Impacts from Air Quality in the Lower Fraser Valley Airshed"

RWDI AIR Inc (for British Columbia Lung Association)
"Health and Air Quality 2005 - Phase 2: Valuation of Health Impacts from Air Quality in the Lower Fraser Valley Airshed"
July 15, 2005
On the Web
Relevance: high

This study estimates that a 10% reduction in fine particulate matter and ozone pollution in the Lower Fraser Valley (LFV) could produce $195+/- $122 million annually in 2010 (2003$ discounted) in health benefits. (I think these are not only direct health costs, but also use some other valuation method.)

  • The study uses a linear model and assumes no thresholds, so the estimates are scalable to 1%, 20%, etc. The authors say that a 1% improvement would save $29 million (undiscounted) in 2010.
  • They also note that the benefits from a given improvement in PM2.5 are about 10 times greater than the benefits from a similar improvement in ozone.

More notes...


British Columbia 2003 - Air Quality in British Columbia, a Public Health Perspective

British Columbia Provincial Health Officer, Ministry of Health Services.
Every Breath You Take…Provincial Health Officer’s Annual Report 2003.
Air Quality in British Columbia, a Public Health Perspective.
2004 Victoria, BC
On the Web
Relevance: high

This report covers the sources, distribution, and health effects and costs of air pollution.

Sources and distribution: Air pollution is neither evenly distributed around BC nor concentrated in Vancouver. For example, Vancouver has relatively low levels of particulate matter (excluding road dust) and ozone but relatively high levels of NO2, SO2, and CO. In the Lower Fraser Valley air shed (including Whatcom County, WA):

  • mobile sources (excluding marine vehicles) account for 41% of smog-forming pollutants. according to an inventory in 2000. 
  • 83% of CO comes from light-duty and off-road vehicles
  • light-duty vehicles are responsible for 23% of NOx, 23% of VOCs, 3% of PM2.5

Health effects. The report estimates that 712 hospital admissions and 944 emergency room visits are due to outdoor air pollution. It also very informally estimates that the health burden from outdoor air pollution costs CAN$85 million annually. Estimates of annual deaths from outdoor air pollution range widely.

  • Low estimate: 82
  • Low intermediate estimate: 25-250
  • High intermediate estimate: 115-402
  • High estimate: 644
  • Estimate of delayed mortality for PM2.5: 71-110