Figuring Out Air Pollution

The International Agency for Research on Cancer, a division of the World Health Organization, published a new study of the impact of air pollution on public health.  The study found that both outdoor air pollution generally, and particulate matter specifically, should be classified as carcinogenic to humans.  According to Dr. Kurt Straif, Head of the IARC Monographs Section, “We now know that outdoor air pollution is not only a major risk to health in general, but also a leading environmental cause of cancer deaths.” The two major sources of outdoor air pollution are transportation and generating electricity.

This study builds on the steady drumbeat of research confirming and quantifying the impact of air pollution on health of those who breathe it. This summer, MIT researchers found that air pollution causes 200,000 early deaths each year. Emissions from road transportation were found to be the most significant contributor, causing 53,000 premature deaths annually. In the nationwide maps of air pollution mortality, Metro Atlanta shows up as a hot spot for transportation-related deaths.


The annual average concentrations of fine particulates from (a) electric power generation; (b) industry; (c) commercial and residential sources; (d) road transportation; (e) marine transportation; (f) rail transportation; (g) sum of all combustion sources; (h) all sources

At the same time, the Atlanta Regional Commission has begun exploring new ways to quantify transportation air pollution on a project-specific level.  Called AREES (Atlanta Roadside Emissions Exposure Study), the project attempts to refine the scope of air pollution models from regional to local.  Doing so would allow the air pollution impacts of particular projects to be modeled, which in turn can be used to select less polluting projects and appropriate mitigation strategies.

Areas of Increased Exposure to Air Pollution Resulting from Widening Marietta Street as Modeled by ARC

Areas of Increased Exposure to Air Pollution Resulting from Possible Widening Marietta Street as Modeled by ARC

We know that breathing air pollution isn’t good for you. We know that vehicle exhaust is a primary source of air pollution.  But on both the public health side and the transportation planning side, efforts are underway to improve our understanding of how these systems work.  The better we understand the problem, the more equipped we are to address it.


Studying the WalkUP Study

Christopher Leinberger’s recent report on development in Atlanta, “WalkUP Wake-Up Call: Atlanta,” has garnered a lot of press both locally and nationally.  Encouraged by the author, the headlines question whether the report shows the end of sprawl in Atlanta. That may be a logical inference, but the report isn’t really about sprawl.  Instead, the report focuses on the emergence of walkable development (what the report calls “WalkUPs) as the increasingly dominant form of development  in Metro Atlanta.

The report begins by making the economic case for walkable development in Atlanta:

  • Average rent in all real estate products in established walkable areas is 112 percent higher on a rent-per-square-foot basis than drivable suburban real estate;
  • Average annual office rent in established walkable areas is $18.55 per square foot, a 30-percent premium over the $14.23 for drivable suburban office rents.  Valuations of office space are significantly higher in walkable areas.
  • Rental housing in regionally significant walkable areas has an average vacancy-adjusted rent of $14.67 per square foot. In contrast, drivable suburban areas averaged $13.07 per square foot for this product type—a 12 percent premium.

Given these price premiums, it shouldn’t be surprising that real estate investment is flowing toward these walkable urban areas (and at the expense of less profitable auto-focused developments).  In fact, the report’s bottom line is that walkable urban development has emerged as the dominant force in metro Atlanta real estate.

percentage built

Share of Non-Residential Property in Walkable Areas Over Recent Real Estate Cycles from “WalkUP Wake-Up Call: Atlanta”

The report also identifies and evaluates what it considers to be the region’s emerging walkable areas.   Although they do not currently meet the report’s definition of walkable,  their combination of “land, supportive policy, place management, infrastructure, etc.” position them for walkable development in the coming years.

Comparison of Metro Atlanta Emerging Walkable Areas

 Comparison of Metro Atlanta Emerging Walkable Areas from “WalkUP Wake-Up Call: Atlanta”

The report has not been without critics.  In a USA Today article titled “Atlanta No Longer Sprawl City?”, Wendall Cox and Joel Kotkin point out that the fastest growth over the past ten years has occurred in suburban and exurban areas.  This response misses the point, not once but twice.

First, whereas the critics focus on a location (the suburbs), the report talks about a type of development (walkable urban).  A suburban location does not preclude walkable development; in fact, many of the report’s 19 emerging or potential walkable areas are located in suburban areas: Gwinnett Place, North Point, Perimeter, Cumberland, Windward, Morrow, and Serenbe.

Second, the report concludes that investment in walkable urban areas is an emerging trend. Development data from the last three real estate cycles, spanning the past two decades, shows that the walkable urban’s share of the development market has grown from 14% (1992-2000), to 26% (2001-08), to 60%.  Relying on decade-old Census data misses the inflection point in the late 2000s and fails to acknowledge the emerging trend.

Touting the end of sprawl certainly makes a more attention-grabbing headline. But the report is really telling us where the development market is going and what it will look like.  From a policy and planning perspective, what’s ahead of us is much more important than what we’ve left behind.






Cycling in the City

City of Atlanta distributed the following “Bicycle Transportation Goals” at its recent Bike Expo:

Cycle Goals

 Nothing new in the handout, but a positive vision and steps in the right direction. For more info on cycling in the city, check out WABE’s story from this spring, the City’s Cycle Atlanta plan, and the Cycle Atlanta smartphone app.


My Plans and Your Plans

At the State Transportation Board’s recent meeting, Georgia DOT updated its Statewide Strategic Transportation Plan and described plans for a more comprehensive plan revision over the next two years.  This larger revision will synch the state-level SSTP with the federally-required Long-range State Transportation Plan.

Performance Dashboard for Fatalities on Georgia’s Roadways

A McKinsey consulting company study run through the General Assembly in 2009’s SB 200, the SSTP attempts to implement the use of performance metrics in evaluating the state’s transportation performance and directing its transportation decisions. The SSTP proved prescient in this respect, anticipating MAP-21’s emphasis on performance measures as a way to ensure that federal funding actually accomplishes federal transportation goals.  The 2013 SSTP Update, and the Plan Progress Report from earlier this year, show that Georgia is increasingly using these metrics to guide its transportation decisions (or at least increasingly using SSTP terminology to describe its decisions).

However, these documents also illuminate several key areas where progress isn’t being made: in transit investment, in linking land use and transportation decisions, and in improving environmental quality.  Despite being identified as SSTP investment priorities, Georgia’s progress in these areas has been modest at best.  (In fact, the 2013 Plan Update’s performance measure for environmental quality is “to be determined.”)

At the federal, state and local levels, all trends point toward greater use of performance measures in transportation planning.  For too long transportation decisions have driven more by political goals than transportation ones.  But facing transportation needs that far outstrip any plausible funding scenario, it is imperative that we understand exactly what we are buying and what it will do.

The SSTP and its use of performance measures are a good start.  But this new version of the plan – SSTP version 2.0 – must build on that foundation and adapt to address its shortcomings. GDOT must identify the targets that are not being met (transit, linking land use and transportation, environmental quality) and refine its approach accordingly.  The goal of performance-based planning is not just to know how we are doing, but to provide information and motivation to fix the problems.