Cascadia Scorecard Weblog

Principles of the State of the Union Address

I hadn't intended to join the cacaphony of bloggers and pundits who are Monday-morning-quarterbacking the State of the Union address. But NEW's all-star board member, Laura Retzler, asked a great question last night that I've been puzzling over since: what's NEW's take on Bush's plan to end the nation's addiction to oil?

It later occurred to me--too late to answer Laura--that my reply should have been rather obvious to me. NEW is developing a concise statement of values and principles, that will orient and unify our research. Among these values are two that are especially germane to energy security: "make prices tell the truth" and "build complete, compact communities."

In his speech Bush called out technological innovation as the primary way to break the addiction. Certainly he's right that technology should play an important part in diversifying our energy portfolio--especially certain types of biofuels, new clean energy sources, and lighter-weight vehicles, for just a few examples that NEW promotes. Yet technological solutions may not be the surest path to ending our addiction.

That's where NEW's principles come into the picture.

"Making prices tell the truth" is especially important. The price of gasoline does reflects only the direct costs of extracting, refining, and distributing it, not the full costs that are externalized to society, such as air pollution, climate change, and even entanglement in unstable regions. By the same token, "free" parking often carries with it high costs, similarly externalized. With a smart restructuring of parking incentives, including parking taxes, there's reason to believe we can achieve substantial gains in both energy efficiency and conservation.

Another of the principles, "build complete, compact communities," would improve home energy consumption and render driving, which has high energy demands, optional or even irrelevant for many people. We already know that compact urban development with good transit and pedestrian alternatives yields dramatic reductions in energy need, even while it boosts health for residents.

NEW's principles may not point to flashy promises of zero-pollution cars or safe nuclear energy. (And they may not come with strings attached to big subsidies.) But they point to hidden levers in our economy and society--small tweaks that can yield outsize results for energy security.

So that's may belated reply, Laura. Thanks for setting me to thinking about this.

*********

By the way, here's the full text of Bush's remarks on energy last night:

Keeping America competitive requires affordable energy. Here we have a serious problem: America is addicted to oil, which is often imported from unstable parts of the world.

The best way to break this addiction is through technology. Since 2001, we have spent nearly $10 billion to develop cleaner, cheaper, more reliable alternative energy sources, and we are on the threshold of incredible advances. So tonight, I announce the Advanced Energy Initiative, a 22 percent increase in clean-energy research at the Department of Energy, to push for breakthroughs in two vital areas. To change how we power our homes and offices, we will invest more in zero-emission coal-fired plants, revolutionary solar and wind technologies, and clean, safe nuclear energy.

We must also change how we power our automobiles. We will increase our research in better batteries for hybrid and electric cars, and in pollution-free cars that run on hydrogen. We will also fund additional research in cutting-edge methods of producing ethanol, not just from corn but from wood chips, stalks or switch grass. Our goal is to make this new kind of ethanol practical and competitive within six years. Breakthroughs on this and other new technologies will help us reach another great goal: to replace more than 75 percent of our oil imports from the Middle East by 2025. By applying the talent and technology of America, this country can dramatically improve our environment, move beyond a petroleum-based economy and make our dependence on Middle Eastern oil a thing of the past.

Slim City

New studies of King County, Washington find that sprawl is linked to dirtier air and bigger bellies. Walkable neighborhoods (those places with higher residential density, more street connections, and nearby to shops, schools, and parks) appear to be healthier for residents and less damaging to air quality--even when taking into account age, income, education and ethnicity.

A few key findings (liberally excerpted from the full coverage in the Seattle Times):

• On average the Body Mass Index — a measure of height and weight — of residents of the more walkable neighborhoods was lower, and they were more likely to get 30 minutes of daily exercise.
• People who lived and worked in more walkable neighborhoods produced fewer pollutants associated with smog.
• A 5 percent increase in a neighborhood's walkability index was associated with a 0.23-point drop in Body Mass Index. Bigger changes in a neighborhood's walkability would be expected to produce greater differences in weight.

All I Want for Christmas is a Sidewalk

It's the most dangerous time of year to be a pedestrian or a bicyclist: short days mean commutes in the dark, overcast weather obscures pedestrians even during daylight, and rain and snow increase the stopping distance for both drivers and cyclists. But as the Seattle Times reports, better infrastructure, such as in Washington's recently updated wish list of pedestrian and cyclist projects, can make walking and biking both safer and more convenient -- not just in wintertime, but year round.

Periodically King County compiles reports on the causes and situations surrounding pedestrian deaths, most recently for the years 2000 through 2003. In short, most fatalities occur when pedestrians either (a) do not follow traffic regulations, and/or (b) are impaired by age (old or young) or alcohol.

This suggests two things to me. First, that walking is fairly safe if you are a sober, law-abiding adult, especially if you have a safe place to walk. But in King County nearly 13 percent of the pedestrians were hit walking on a road without a sidewalk. And while people over the age of 60 made up one out of every four deaths, most were following the law and crossing in a crosswalk. With limited mobility, seniors often take more time to cross, so changes such as longer signal times and better lighting at crosswalks can make a big difference.

Second, because responsible walking is not as dangerous, building safer places to walk, and advertising them, could not only reduce pedestrian fatalities, but also encourage more walking. (And as we've reported before, there seems to be safety in numbers for pedestrians -- that is, the more pedestrians there are on the streets, the lower the odds that they'll be struck by a car.)

Reading this and other pedestrian fatality and safety studies, it seems to me that, yes, pedestrians need to be visible, follow the law, and look well before crossing the street, but they also need a decent infrastructure for walking -- including sidewalks, bike paths, streetlights, and signaled street crossings. Other countries with much higher pedestrian rates also have much lower fatality rates. We can do better, too.

Sloth: Perhaps not a sin, but still deadly

Today's Seattle Times summarizes the findings of a long-term study of how exercise improves health:

People who engaged in moderate activity — the equivalent of walking for 30 minutes a day for five days a week — lived about 1.3 to 1.5 years longer than those who were less active. Those who took on more intense exercise — the equivalent of running half an hour a day for five days every week — extended their lives by about 3.5 to 3.7 years, the researchers found.

In other words, sloth kills, and even moderate exercise can lead to a longer, healthier life.  Which is something to keep in mind next time you're in the market for a place to live -- choosing a home where it's as convenient to walk to the store as to drive could actually save your life.

Portland, Rethunk

Interesting stuff in today's "Rethinking Portland" issue of the Portland Tribune. The Trib explains the rationale for the special series thus:

For decades, Portland has been viewed across the nation as an icon of livability and progressiveness, a community that introduced the nation to regional planning and prevention of big city sprawl, a steward of the environment and a proponent of diverse transportation systems, including light rail.

But as we take stock of Portland today, and look forward, we are compelled to say there is much that we urgently need to improve upon.

Seems about right to me -- there's always room for improvement, no matter how good your national reputation.  Indeed (as we discussed in this book) despite Portland's reputation for preventing sprawl, it's trailing far, far behind its northern neighber, Vancouver, BC.

Two articles in the series stood out for me.  First, Jim Redden reminds us that, as assiduously as our government measures economic indicators like GDP, city officials still flying blind when it comes to understanding how middle-income Portland residents are faring.  The US Census bureau estimated that median income for a family of four in Portland was $40,783; the US Department of Housing and Urban Development estimated that it was $67,900.  Part of the difference can be explained by differing geographies; the HUD figure seems to cover the Portland suburbs, while the Census seems to cover just Portland proper.  Still, it seems odd that, given all the resources devoted to measuring aggregate economic output, Portland city officials need to convene blue ribbon panels of economists just to figure out how much the middle class earns.

Second, Todd Murphy agonizes about the decision to raise his kids in Portland, or to head to the suburbs.  Obviously, it's not an easy choice; even for someone who's spent his life in the city, there are plenty of reasons to find the suburbs an attractive place for a family. But one of Murphy's biggest concerns is safety -- particularly, that there's violent crime in a city that you just don't find in the suburbs. 

But what Murphy doesn't consider in the article is the risk of car crashes:  the risk of a fatal traffic accident is roughly proportional to the number of miles you drive.  So people who live in compact neighborhoods are generally at lower risk of dying in a car crash, whether as driver, passenger, or pedestrian, than people who live in car-dependent suburbs. I don't know about Portland in particular, but this study suggests that, when you combine the risk of dying in a car crash with the risk of being killed by a stranger, central cities tend to be safer than far-flung exurbs.

My Bad

Whoops: it looks like I got much of this post simply wrong. 

To recap, Brookings Institution scholar Margy Waller wrote an article in the Washington Monthly promoting car ownership for the working poor (which strikes me as reasonable, on balance), and also proposing a $100 billion annual federal tax credit to subsidize commuting costs (which stuck me as wrong-headed).

But one of the reasons I so strongly disliked Waller's commuting subsidy was that I assumed -- apparently wrongly -- that she was proposing that more expensive commutes be given bigger subsidies.  That, in my view, would create all kinds of perverse incentives, the worst of which would be to subsidize sprawl, by giving people who live in the most inaccessible locations, with the longest, highest-cost commutes, the biggest payouts.

But Ms. Waller herself now informs me that, while it wasn't spelled out in her Washington Monthly article that floated the idea, it was never her intent to link the amount of the tax credit to the cost of commuting.  Rather, people with any commuting costs would be eligible for the exact same credit.  So, if you have a choice between a cheaper commute on transit, and a more expensive one in a car, you can choose the cheap commute and pocket the rest of the tax credit as a bonus.

That seems a lot more reasonable than I first thought, as it doesn't exclusively favor longer and more expensive commutes.  So even though I'm still quite cool to the idea, I take back what I said about it being nutty.  Sorry, Margy!

There are still plenty of reasons to be skeptical about a commuting tax credit, though.

First, it clearly favors motorized vs. nonmotorized commutes -- that is, you'd have to spend money on your commute in order to qualify for the credit.  So folks who are lucky enough to be able to walk to work get nothing; folks who bus or drive get a credit.  This is essentially begging people to rack up commuting costs, even if they don't need them.  It's also asking them not to walk for transportation -- which studies now suggest is a contributing factor in the twin epidemics of obesity and physical inactivity.

Second, it still seems strange to me to focus on subsidizing commuting costs, rather than raising income generally.  That is, if I had to choose between a generalized earned income tax credit (one that helps all low-income workers, not just those with commuting costs) and a tax credit focused specificially on commuting costs, I'd prefer the former.  As to the argument that folks with young children really need a car -- well, not all low-income folks have kids.  And some of those who do might prefer to use a tax credit for child care and a short commute, or on a home near convenient transit, rather than spending (or wasting) some of the tax credit on a car.  I'd prefer to let them decide what to do with their money.

And third, this kind of proposal seems to be just the sort of thing that could get mangled in the political process.  Sure, the original proposal wouldn't favor longer commutes.  But after it gets through the rural-dominated US Senate -- not to mention the auto-industry and oil lobbies -- perhaps it would.

In the end, if I had to spend $100 billion a year on a program to lift the prospects of low- and middle-income Americans, I'm not sure that this is the way I'd do it.  But it's probably not as terrible an idea as I thought at first.

A Beacon in the Smog

I doubt that most residents of leafy suburbs paid a lot of attention to air quality when they chose their homes.  But it’s not hard to believe that, when suburban commuters return home from work each night, they breathe a little easier in the belief that they’ve escaped the smog and fumes of the city.

Only, maybe they haven’t.  At least, not in the greater Puget Sound, anyway.

The Puget Sound Clean Air Agency maintains a network of air monitoring stations throughout the region.  Some are in central Seattle, some in smaller cities, and some in suburbs and rural locations.  And--perhaps surprisingly--there doesn’t appear to be a decisive air quality advantage to living in the suburbs.  (See this pdf for more details.)

Or, to be a little more accurate:  air quality tends to be both highly variable and very localized.  Monitoring stations in the neighborhoods surrounding Seattle’s downtown tend to report that the air is pretty clean -– cleaner, in some cases, than at more suburban monitoring stations in Bellevue, Lynnwood, or Lake Forest Park.  On the other hand, the air in Seattle’s industrial zones can be pretty dirty; but then again, so can the air in Kent and Marysville.

The Beacon Hill monitoring station, a mile or so southeast of downtown Seattle, is worth a special mention. 

The Beacon Hill neighborhood is just to the east (i.e., downwind) of I-5, the heavily trafficked West Seattle Bridge, and the Port of Seattle; to the north it's bordered by I-90.  Given its location, you might expect the air quality on Beacon Hill to be pretty bad.  In fact, if you had to pick one residential neighborhood in Seattle that’s likely to have outdoor air quality problems, Beacon Hill might well be it.

But Beacon Hill’s air is, surprisingly, pretty clean. For fine particulate matter (i.e., soot, largely from diesel vehicles), it does moderately well: 3rd best of 7 regional monitoring stations by one measure, 7th of 16 by another, best among 5 by yet another.  It has less ozone than any other monitoring station in the region (not surprisingly, as concentrations of ground-level ozone are typically lower in city centers than in leafy suburbs and exurbs).  And its carbon monoxide levels were the lowest among 7 stations.  I'm not sure why Beacon Hill does as well as it does -- perhaps it's just a function of altitude and prevailing wind patterns. But whatever the reason, it's good news for the people who live there.

Clearly, the monitoring station results don't offer definitive proof that Beacon Hill residents have nothing to worry about from their air.  But it does mean that a move from Beacon Hill to, say, Lynwood or Bothell or Lake Forest Park or Marysville—all suburban locations—won’t necessarily buy cleaner air.

Three more points are worth mentioning here.  First, as we mentioned in this post, the air in your car is typically among the worst you’ll breathe all day.  Second, for most pollutants, indoor air is more polluted than outdoor air –- and most people spend 90% or more of their time indoors.  And third, outdoor air quality seems to have improved pretty substantially since the early 1980s; King County has had no “unhealthy” air quality days since 1999, and only 31 days in 6 years in which the air has been “unhealthy for sensitive groups.”  That’s not a perfect record, obviously, but it does represent a substantial improvement from where we once were.

To me, these facts suggest that at this point improving the air that you breathe depends, in large measure, on keeping yourself off the highway, and keeping hazardous products out of your home.  Obviously, clean outdoor air matters too -– it’s just that living in the suburbs doesn’t necessarily guarantee that you’ll get it.

Update:  I should mention that "A Beacon In The  Smog" is, or at least was, the official tag line of Grist Magazine.  Plagiarism, like imitation, is a sincere form of flattery.

King of Sprawl

Does sprawl kill?  Looks like it.  This study found that people who live in sprawling counties -- places with low population densities and poorly connected street grids, and with rigid segregation between stores, businesses and residences -- are more likely to die in a car crash. 

Apparently, living in the sort of place where you can't get anywhere without a car makes you drive more.  And people who drive more tend to crash more.  (When you put it that way, social science seems pretty simple, no?)

But, of course, the question remains:  how much?  How much more accident risk do residents of sprawling places really face? The answer is surprisingly straightforward: according to the model developed by the study's authors, residents of Washington's King County (relatively compact and urban) should face a 20 percent lower risk of getting in a car crash than the people who live in neighboring Snohomish County (relatively sprawling).

That's the theory at least.  And in this case, the theory matches up pretty closely with reality.  Over the last few decades, the age-adjusted traffic fatality rate in King County has averaged about 20 percent lower than the rate in Snohomish.  (See table E-8, here.)

Or, said another way: if King County sprawled like Snohomish, about 800 additional King County residents would have died in car crashes since 1980.  And since the National Safety Council estimates that each traffic fatality is associated with 54 non-fatal injuries, King County residents also avoided more than 40,000 injuries, just because of how its urban and suburban areas are laid out.

Now, just imagine how many fatalities could have been avoided if King County looked like greater Vancouver, BC.

Charming 3-bedroom, 2 bath with only 5 pounds of weight gain a year

Obesity has many causes, but current research indicates that sprawl may play a part. So far, researchers have concluded that people who live in sprawling, car-dependent neighborhoods are more likely to be obese, while people who live in walkable neighborhoods are apt to do more walking. But researchers still trying to tease out cause and effect: do walkable neighborhoods encourage people to walk? Or do people who like to walk move to walkable neighborhoods? I suspect it is both.

However, one recently study claims that sprawl doesn't, in fact, cause obesity. The authors, who base their findings on a complex theoretical model, don't dispute that sprawl and obesity are linked. But they claim that people who move to sprawling neighborhoods are simply making a more-or-less conscious choice to put on more weight:

"[R]esidents are willing to accept locations that result in weight gain because they face lower housing prices and can purchase more housing."

In other words, people buying a house don't mind putting on a few extra pounds in order to get the house they want.

But here's the catch: the link between sprawl and obesity just isn't that widely known. Researchers have just been started exploring these connections over the last few years; the literature is growing, but it's still in its infancy. So it's hard to imagine that most home-buyers, over the last several decades, were weighing the concrete effects of neighborhood design on their health. How could they, when the information just didn't exist?

While I haven't worked through the entire model line-by-line, I also have some quibbles with the methods. As with any theoretical model, it's based on a host of assumptions.  And one of them -- that calorie consumption increases as income increases -- clearly poses problems. As Clark blogged about a while ago, food is really cheap, and cheapest foods are the most calorie dense (think greasy fast food). So there's ample reason to believe that calorie consumption could actually increase as income goes down. 

Theory can be very useful; and there may well be some truth to the notion that people who don't like exercise don't mind living in places that discourage walking. But in this case, only studies that track actual people over time as they move among actual neighborhoods will yield reliable answers.

Friends for Life

There's no question that our social environments help determine how healthy we are. In fact, I have now in front of me a small mountain of studies to that effect. Rather than bore you with the particulars of their findings, I'll simply summarize this way: study after study shows that close social relationships--a spouse, loved one, or a close friend--help people live longer.

Interestingly, social bonds don't appear to prevent the onset of a disease. There's no association, for instance, between social isolation and sudden cardiac death. But for survivors of a life-threatening event or disease, social connectedness significantly increases average longevity and functioning. One study even suggests that the effect of social isolation "is comparable to the effect of cigarette smoking on total mortality reported in some studies." 

In other words, close relations with friends and family are really, really good for your health.  Or--stated in the converse--loneliness kills.

Perhaps more intriguing, an emerging body of research is pointing out that suburban sprawl is an impediment to social networks. Does sprawl erode social networks which are critical for health? Is sprawl bad for our health because it diminishes our personal relationships? Well, that's where things get confusing.

I've already aired my skepticism that sprawl erodes social capital. (Or more precisely, I'm skeptical that the existing research proves it.) But for the moment, I'll abandon my skepticism and go along with the multitude of voices arguing that sprawl is bad for social capital. And indeed, there is some compelling research showing that traditional city neighborhoods are better at fostering incidental contact between neighbors and promoting loose associations that may be important for well functioning civil society and even democracy. Plus, it's clear that declining social capital over the last several decades has been coincident with ever-more dispersed suburbs and highways.

One might be tempted to conclude that if sprawl is bad for social capital (which is good for health), then sprawl must also be bad for health. One would even have plenty of company among researchers who have claimed just that. But one would still have to convince me. Here's why.

My reading of the available literature suggests that there's a pervasive equivocation at work. The term "social capital" (or, variously "social networks" or "social ties") is used in at least two different ways. In one sense the term(s) refers to informal neighborhood associations, participation in civic life, or belonging to a church or community group. I'll call this "loose social capital." In the other sense, the term(s) means the presence of close supportive individuals, such as a spouse. I'll call this "tight social capital."

The research makes it clear that tight social capital is good for health, but I haven't heard of anyone arguing that sprawl reduces tight social capital. Moreover it's not at all clear that loose social capital--the kind that is allegedly eroded by sprawl--has anything at all to do with health outcomes. But because the literature's terminology for both tight and loose social connections are the same--social capital--it's easy to assume that they are the same thing and have the same effects.

Now, admittedly, there is some evidence to suggest that people with more friends are healthier (and this is especially true for men for some reason). But that, of course, doesn't mean that having friends makes you healthier. And it's also true that at least one study shows that too many social connections can actually be inimical to health--interpersonal conflicts cause stress-related diseases (and, again, this is especially true for men for some reason).

I do think there's probably a link here--that is, a link from sprawl to loose social capital to health--but I'm not quite convinced yet. The best research I've seen is from Ichiro Kawachi, a Harvard researcher. On a state-by-state basis he examined the results of two simple questions that have been found to be closely correlated with loose social capital---Do you think most people can't be trusted? and Do you think most people would take advantage of you if given the chance?

States where people thought they couldn't trust others also had worse rates of self-reported health. And states where people felt that others would take advantage of them had higher mortality rates. So Kawachi's study makes me think that there must be some connection between loose social capital and health. And if sprawl does indeed weakens loose social capital, then it may be to blame for worse health outcomes. I'm hoping there's more research emerging that will document these connections, if they exist. In the meantime, I'm also hoping not to find more research that seems to equivocate between loose and tight social capital.

Postscript: In a curious though unrelated side note, one study found that among spouses, husbands had a higher risk of depression if their wives suffered a cognitive disability. On the other hand, if their husbands suffered a cognitive disability, wives were at no greater risk for depression. I'm not really sure what to make of that.

Chain of Evidence

From CNN, a story suggesting that Oregon's emphasis on pedestrian and bike-friendly cities has helped it keep obesity in check.

According to a study released Tuesday by the Washington, D.C.-based Trust for America's Health, the percentage of overweight Oregonians held steady at 21 percent last year, a sharp contrast to Alabama, where the rate of obesity increased 1.5 percentage points to 27.7 percent.

What makes Oregon different is its emphasis on urban design, which encourages outdoor activities like biking to work, the study's authors said.

Now, obviously, only a small share of Oregon residents walk or bike to work; and many people who do so have farily short commutes. But that's exactly the point:  when it comes to obesity, even a little bit of exercise can make a big difference.  On average, adults put on a pound or two a year -- but a pound of extra weight per year averages out to just 10 calories per day.  That's less than a teaspoon of sugar, or a daily stroll of about a tenth of a mile.  So even though Oregon cities' neighborhood design may have only a small effect on walking and biking, that effect could very well have been enough to keep Oregonians from putting on as much weight as Alabamans.  And by curtailing the growth of obesity, Oregon may have helped keep its citizens healthy, while stemming health care costs--which now account for about one out of every eight dollars Oregonians earn.  Which is one way of responding to people who question whether sidewalks and bike lanes are really worth the cost.

Obesity Grows

Obesity rates are growing in every state but Oregon, according to a new report by Trust for America's Health based on data from the CDC. (Read the Seattle Times article here.) While Oregonians can be proud of their accomplishment last year, they are not the trimmest state in the country, nor in the Northwest.

Interestingly, every Northwest state has lower rates of obesity than the national average. Montana residents are least likely to be obese; Alaskans are most likely. As Jessica pointed out recently, it's worth paying attention to obesity trends, not only because of their health consequences, but because it can absorb a lot of money.

Here's the skinny on obesity in the Northwest states...

Percent of state residents who are obese, 2004

	Percent of residents who are obese, 2004
Alaska	23.5
California	21.5
Idaho	20.9
Montana	19.1
Oregon	21.0
Washington	21.7
United States	24.5

Medical Cost of Obesity

The US national rate of obesity has doubled since 1990, so that in 2004, nearly one-quarter of Americans (23.1 percent) were classified as obese. Medical studies have established clear links from obesity to a variety of medical conditions, including type 2 diabetes, high blood pressure, cardiovascular disease, and others. Obesity is also costly: the increasing prevalence of obesity and costs of treating obesity-related diseases has helped to fuel the recent rise in medical spending. By one estimate, 27% of the cost increase from 1987 to 2001 was due to obesity.

The latest studies estimate that obesity alone costs the US around $75 billion annually, while while the added costs of treating conditions brought on by simply being overweight bring that share up to 9.1% of total US medical expenditures. On a regional level, obesity alone costs the Northwest over $2.3 billion dollars a year. That’s around 0.5% of our gross state product (see table below).

	1990 Obesity Rate	2004 Obesity Rate	Annual medical spending on obesity 2003 dollars (% of all med. spending)
US	11.6%	23.1%	$75,000 million (5.3%)
WA	9.4%	22.1%	$1330 million (5.4%)
OR	10.9%	21.2%	$781 million (5.7%)
ID	11.9%	20.8%	$227 million (5.3%)

On an individual level, obesity increases annual medical spending per person by 37.4%, or around $730 a year. And overweight increases spending per person by 14.5%, or $247 per year.

The medical cost of obesity is a meaningful drain on our economy, and the costs listed here are only the direct medical expenditures. Not included are the indirect costs of lost productivity, lower quality of life, or years of life lost due to obesity-related illnesses.

While obesity is caused by many factors, studies indicate that the built environment is one influence. Sprawling neighborhoods designed for driving everywhere--with few sidewalks, nearby desirable destinations, or a direct route to destinations--can discourage residents from walking or bicycling. One way to fight obesity (while improving our quality of life) could be to redesign the places we live.

For Clean Air, Work Downtown

In our ongoing quest to discover how land use and urban form links to human health effects, I recently stumbled across something odd. It's a 2000 study of vehicle emissions per household in Puget Sound, authored by Larry Frank. I wanted to find out if there is a connection between air pollution and urban density. According to this study, there is, but in a way I didn't expect.

It turns out that the strongest land-use correlate to low household emissions is not residential density, but job-site employment density. That is, from a statistical standpoint, it matters less whether you live on Capital Hill or the Sammamish Plateau than whether you work in downtown Seattle or Bothell. The difference, I suppose, is that downtown Seattle and other places with high employment density are well-served by transit and are generally easier to get to with lower vehicle emissions than more far-flung workplaces.

Interestingly--this is only interesting if you're a geek; otherwise skip to the next paragraph--the drop in household emissions does not observe a linear relationship with employment density. For the lowest three quartiles of employment density household emissions are about the same (they're a little higher in the lowest density quartile), but then they drop off sharply at the beginning of the highest density quartile. This suggests that there's a threshold of employment density--perhaps the density at which transit, carpooling, etc become viable--after which emissions drop quickly.

It's also interesting, I think, that in this study residential density is less strongly correlated with lower household emissions. There is still a correlation--higher residential densities meant less vehicle emissions--but the difference, while significant, was relatively minor.

One reason perhaps emerges in another set of correlations. This study found that households located in census tracts with high employment density, greater mixes of land-use, and greater street network density--in other words, places with many characteristics of city living--actually generate more vehicle trips and more vehicle trips with a cold engine (which produces a disproportionate share of tailpipe emissions). Probably, this is because there are more services and amenities nearby and there's less incentive to "chain" trips together as a typical suburban commuter might on the way to or from work. Even so, the higher density households produce fewer emissions simply because the trips are not as long as for households in lower densities.

There's a lesson here, maybe, for those of us interested in urban form as well as everyone who's interested in improving air quality. From a public health perspective, it may make more sense to concentrate jobs in dense nodes with good transit access than to worry about other land-use features. Maybe the best reform to reduce vehicle emissions is more office space downtown.

About the study: The study uses an exhaustive (heh, heh) methodology that calculates three types of emissions (NOx, CO, and VOC) that accounts not only for driving distance, but also for speed, travel time, and emissions from starting the car (adjusted for estimated engine temperature at start). Its findings are based on data from the Puget Sound Transportation Panel Travel Survey, which records travel for 1,700 households over a two-day period by giving each member of the household over 15 a diary for recording trips and their characteristics.

UPDATE 8/10/05: Here's a link to an abstract of the study. As far as I know, the full version is not online.

Waiting to Inhale

People who move to the suburbs may think they’re fleeing the polluted air of the city.  Of course, there’s a tradeoff: by living in low-density suburbs, they spend more time in their cars. And as it turns out, the air inside your car may be just about the dirtiest you’ll breathe all day.

Last year, researchers in Sydney, Australia released a study (pdf) that measured the levels of benzene (a carcinogen) and other volatile organic compounds (VOCs), as well as asthma-inducing nitrogen oxides, among people who commute by car, bus, train, bike and foot.

The verdict? Car commuters breathed the worst air, getting the highest doses of benzene and other VOCs. Even bus commuters were exposed to lower levels of VOCs than car commuters (though bus riders breathed higher levels of nitrogen dioxide). Train commuters had the least exposure overall, with cyclists and walkers coming in second-best.

One reason for the difference is that motorists are breathing exhaust, both from their own vehicles and from nearby traffic. As the authors of the Sydney study note, driving on congested freeways puts motorists in a "tunnel of pollutants." By contrast, other travel modes reduce ambient exposures: trains tend to run on isolated tracks, buses often take express lanes, walkers and bikers may travel on quieter streets.

The US census says that 87.9% of Americans commute by car, truck, or van, and the National Household Transportation Survey shows that people who live in sprawling suburbs spend about 68 minutes per day in their cars--about 50 percent more than people who live in more compact urban neighborhoods.

So, to some extent, if you want more fresh air it may be smarter to move closer to downtown, rather than farther away.

Collision Course II

Last week, I wrote a post detailing how much car crashes cost.  An alert reader asked some followup questions about how to reduce his risk:

Does a decrease in vehicle-miles translate to a decrease in injuries? Am I relatively safer on my bike? On the bus?

Here are some quick answers.  First:  the more you drive, the greater your chance of getting in a crash.  See, for example, this chart from a Victoria Transport Policy Institute analysis of car crashes in British Columbia:
The relationship is pretty close to linear.  So if you want to decrease your crash risk, the most obvious strategy is to arrange your life so you can drive less, if you can.  Of course, some roads are riskier than others -- and rural two-lane highways are among the riskiest.  Congested urban roads and streets tend to have more crashes per mile driven than average, but fewer fatalities -- slower speeds make crashes less deadly.  Which may be one reason why the risk of dying in a car crash is higher at the urban fringe than in center cities or inner-ring suburbs, and why sprawling cities are more dangerous than compact ones.

Next:  If you want to be safer, take transit.  Measured per passenger-mile, transit buses and commuter rail are about as safe as you can hope for; buses seem to be more than 10 times safer than cars for their occupants, while commuter rail is about 80 times safer.  (But both are more dangerous than cars for other occupants of the roads.)  I wish I could say that biking would make you safer, but it doesn't seem to; mile for mile, biking is about 10 times deadlier than driving. Exercise benefits may partially offset the increased crash risk.

It's a shame that biking is so risky in the US.  Biking fatalities are down, of course -- they fell by 27% between 1975 and 2001 -- but mostly because of a steep drop in cycling by children.  But in Germany, the exact opposite has happened:  the number of bike trips doubled between 1975 and 2000, while the number of bike fatalities dropped by 64%. The difference, according to some researchers, is that public policy in Germany has emphasized bike and pedestrian safety -- including infrastructure, traffic calming, traffic education, and traffic regulations -- while policies in the US tend to emphasize fast travel by car.

One side note--although traffic fatality rates in the US are among the highest in the developed world, US drivers aren't particularly unsafe, nor are the roads we drive on.  Measured per mile, our fatality risk is about average.  The real difference is that we drive much more than our counterparts in other nations--and all else being equal, more driving means more car crashes.

Collision Course

Car crashes kill about 700 Washington residents each year.  Now, remember, that's out of a population of over 6.1 million -- meaning that, on average, your chance of dying in a car crash this year is just over one in 10,000.  With odds that slim, are collisions really such a big deal?

As far as I can tell, yes.  Here's why.

First there's this:  car crashes skew young.  Surprisingly, motor vehicle accidents are the leading killer of Washingtonians between the ages of 1 and 44, reaching a peak between the ages of 15 and 24.  Similarly, for those before retirement age, traffic deaths are third leading cause of shortened lifespans, trailing only cancer and heart disease.  So the significance of traffic accidents to human health is far greater than the absolute numbers might suggest.

And then there's this:  For every traffic fatality, there are about 54 nonfatal traffic injuries and more than 200 collisions that cause no significant injury. And not only do those collisions take a toll in terms of pain and suffering, they're really costly.  According to the National Safety Council, you can get a pretty good estimate of the direct, out of pocket costs of traffic accidents by multiplying the number of traffic fatalities by $5.4 million dollars.  (They estimate that this figure will cover medical costs, lost wages, property damage, and other direct, out-of-pocket costs resulting from collisions.)  Using figures for 2002, that means that traffic accidents in the state of Washington were responsible for about $4 billion in direct economic costs.

But the real economic cost of collisions is probably even higher.  The Safety Council estimates that each traffic fatality results on about $1 million in out of pocket costs, and each nonfatal injury, an average of $45,000.  But these figures doesn't account for pain and suffering, or how much people would be willing to pay to avoid a car crash. 

Now, it's always a bit creepy--and a lot controversial--to assign a dollar value to death or injury.  But there's no question that people don't just consider medical costs and lost wages when they think about their own safety.  The Federal Highway Administration estimates that, based on how much people are willing to pay to avoid dying in a car crash, a traffic fatality costs about $3.4 million in 2004 dollars (the figure in the link, $2.6 million, is in 1994 dollars; I adjusted for inflation).  That figure is lower than that used by EPA, which assumes that people are willing to pay more than $6 million, on average, to avoid death. 

Using these higher figures, the cost of car crashes escalates.  Depending on the assumptions you use, the comprehensive cost of traffic collisions may top $8 billion annually, in Washington State alone.

Just by way of comparison, the Washington State Department of Transportation will spend about $1.7 billion per year (pdf link to budget document) over the next two years on highway maintenance, operations, and construction.  Obviously, the state DOT doesn't pay for all transportation expenses in the state.  But it seems pretty certain that traffic accidents are far costlier than the roads on which they occur.

Have It Your Weight

A look at the fast food industry--an important contributor to the emerging obesity epidemic--courtesy of MSNBC and Newsweek. The skinny (or not so skinny, as the case may be) is that fast food chains like Burger King are getting back to fundamentals: greasy, fat-laden food. Forget about low-fat sandwiches; BK's new strategy revolves around items like the Enormous Omellete Sandwich that tips the scales at 760 calories.

As it turns out "hard core" fast food consumers make up only 18 percent of the general US population, but represent 49 percent of the sales for fast food outlets. The target demographic? Men, 18- to 34-years-old, who don't much like their jobs. BK can safely play to its (ever-expanding) base with increasingly unhealthy menu items, because they can count on industry giant McDonald's taking the flak from what BK's CEO dubs "the nutrition Nazis."

Eat The Rich

Rich people are nearly as likely as poor people to be obese, according to new research at the University of Iowa. USA Today reports that three decades ago, the chance of having a ballooning waistline inversely correlated to having a ballooning paycheck. But that's changed now. 30 percent of all Americans are obsese--defined as being 30 pounds or more above a healthy weight--and there's little difference between Americans of different income levels.

In possibly related news, USA Today also reported that a pub in Pennsylvania now sells a $30 burger that tips the scales with 10.5 pounds of beef, 25 slices of cheese, and a cup-and-a-half of mayo, among other condiments.

And in further possibly related news, the New York Times reports that excessive doughnut consumption is bad for your health. It also wags a mildly reproving finger at the USDA's new and oddly ambiguous food pyramid. Both subjects dear to this blog's heart.   

Death by Traffic

What do the United States, Poland, Portugal, and Greece have in common?  Lots of deaths from automobile accidents.  The US ranked 27th out of 30 OECD nations in traffic deaths per capita in 2002 -- with 30th place (Greece) having the most deaths, and 1st (Turkey) having the fewest.   By contrast, Canada ranked 12th.

Now, it's not that the US has particularly bad drivers, or that our cars are particularly unsafe.  Mile for mile, our vehicle injury rate is right in the middle of the pack; and our vehicle fatality rate, adjusted for miles driven, is actually a smidge better than the OECD average.

Instead, the reason we have so many traffic deaths and injuries is simply that we drive a lot. Part of why that's so is that we're affluent (meaning that we can afford to buy lots of cars) and our gas is cheap.  But most of it has to do with the way our cities have grown.  Sprawling community design has pushed destinations farther apart, making a car a necessity for most trips.  And when you need to drive everywhere you go, you wind up taking on more risk than you'd bargained for.

Live Fat, Die Young

Amidst a spate of new US government publications on healthy eating and exercise, a number of people (myself included) have become increasingly obsessed with whether they're getting adequate nutrition and activity.

But what's strange, I think, is that we're buffeted by countervailing forces that tug at our behavior, and ultimately at our waistlines. We're ever-better informed about the consequences of inactivity and poor diet; and yet it seems we're ever-more susceptible to them. Consider both of these items (a few weeks old) that appeared this March:

• The New England Journal of Medicine published an alarming report that obesity--especially among children and teens--may soon reach such epidemic proportions that it will actually begin to reduce Americans' average life expectancy. (I believe this would be the first time to happen in at least 80 years.)
• Burger King unveiled a new breakfast sandwich dripping with a whopping 730 calories and 47 grams of fat. (For context, a person must run for 5 to 6 miles to burn that many calories.)

Good information may not necessarily be an antidote to the array of unhealthy choices facing us, but it can help, I think. (Check out this handy calculator produced the US Department of Agriculture--you can ascertain your body mass index and appropriate caloric intake given your physical activity.) Information can be a powerful motivator. In fact, it just motivated me to choose a different commuting mode this evening: walking.

UPDATE: The US Food and Drug Administration recommends a maximum daily allowance of 65 grams of fat. All by itself, that Burger King breakfast sandwich accounts for 72 percent of our daily maximum.

UPDATE II: Okay, this one takes the cake. Late last year, the fast food outlet Hardee's started selling their "Monster Thickburger," which has 1,420 calories and 107 grams of fat (not counting the fries or drink). For reference, to burn off the Monster Thickburger's calories you would have to run nearly a half-marathon. And, in a single burger, you would have consumed the daily maximum fat intake for 1 and 2/3 days. (Luckily for northwesterners, Hardees is mainly located in the south and midwest. It doesn't have any locations (yet) in the Northwest, apart from a handful in western Montana.)

Walking Tall

According to the American Podiatric Medical Association, three of the 10 best U.S. cities for walking are in the Northwest:  Seattle (#3), Portland (#4), and Eugene, OR (#8).  Other cities in the top ten, in order, were Arlington, VA; San Francisco; Boston; Washington, DC; New York City; Jersey City; and Denver. The APMA ranking is based on a number of measures of physical activity, ranging from dog ownership to the share of people who go to museums. 

Obviously, to some extent, lists like this are a bit silly -- they project an appearance of precision that just isn't justified.  But on the other hand, maybe living in a walking-friendly city will make up for all of those donuts that I eat.

Resistance Is Futile

This week's US News and World Report has a great article on food -- and, in particular, why it's becoming increasingly difficult to resist overeating.

Although there's been some recent controversy over exactly how bad obesity is for your health,  it's now perfectly clear that rising obesity rates are a major public health problem. And the US News article serves as a great reminder that, as important as it may be to emphasize personal responsibility in maintaining healthy eating habits, America's culture of food--in which high-calorie food is cheap, ubiquitous, and heavily marketed--makes it harder and harder to make healthy choices. The opening paragraph makes  a great teaser for the rest of the article:

It's everywhere. Tank up your car, and you walk past soft pretzels with cheese sauce. Grab a cup of coffee, and you see doughnuts, danishes, and cookies the size of hubcaps. Stop at Staples for an ink cartridge, and you confront candy bars at the register.

Too true.

Now, the classic approach to public health problems is to locate the points of highest leverage, where a few simple changes can make the biggest difference.  The archetypical example hails from London in the mid-1800s, when a physician traced a cholera outbreak to a single contaminated well:  simply removing the pump handle was enough to stop the epidemic.

Obesity, however, seems to be a tougher nut to crack than the cholera outbreak.  There are just too many pump handles, too many interrelated causes:  hectic lives mean less time for exercise; jobs are more sedentary; sparsely populated suburbs make walking incovenient, reducing opportunities for exercise in our daily lives; federal farm subsidies encourage overproduction of corn, wheat and soybeans--American farmers produce enough to give every American 3,900 calories per day--holding down the price of starches and oils; ubiquitous food advertising chips away at our resolve.  Tackling each of these issues would be a major undertaking, especially in today's political climate.  But tackling all of them, to one extent or another, may be necessary to make much headway against the problem.

One thing that everyone seems to agree on, though, is that to really fight obesity, people need to have better information about how to make healthy choices.  Everyone but me, that is: to me, focusing on education is a bit of a distraction. I know perfectly well that donuts are empty calories, that a donut a week can make the difference between maintaining my weight and gaining a pound or two a year.  And I can resist them 90% of the time.  Maybe 99%. 

But if someone leaves free donuts in the office kitchen, eventually, my willpower buckles.  Temptation trumps education--not every time, but often enough to make it perfectly clear that the real solution isn't to fortify my resolve or learn more about the effects of obesity, but to keep the darn donuts out of the kitchen in the first place.

So the US News article is a great reminder of how thoroughly we've surrounded ourselves with donuts.

Run For Your Life

As if eating nine servings of fruits and veggies a day isn't bad enough, now federal health experts are saying we need 60 to 90 minutes of exercise a day.

An article in today's Seattle Post-Intelligencer tries to soften the blow by claiming that 30 minutes is enough for many people. The truth is, 30 minutes is enough to reduce the chances of chronic disease. But adults who want to prevent weight gain need 60 minutes a day on most days of the week; and adults trying to keep weight off need 90 minutes a day. Even worse, weight management requires boosting exercise but not caloric intake, which means that a workout won't justify a bag of potato chips.

To my mind, the new recommendations are troubling (and not just because I love potato chips). In 1999, fully 61 percent of Americans were classified as overweight or obese, meaning that most people need at least an hour of exercise--and probably an hour and a half--on most days to be healthy. That's a huge time commitment, especially in light of recent studies by the Centers for Disease Control that suggest that about one-quarter of Americans exercise almost not at all. And more than half--55 percent--do not reach the recommended minimum of 30 minutes a day on four days a week. (By the way, this definition of exercise even included light activities like sweeping and stretching.)

So not only must people make a lot of time for exercise, they must do so in busy schedules that may not currently accommodate fitness. It strikes me that only large-scale shifts in our lifestyles will allow us to get enough exercise.

Luckily there may be policy remedies that can help address the persistently unhealthy lifestyles that many Americans are living. Specifically, policymakers can promote an urban form that prizes muscle power over internal combustion. (Interestingly, a recent study by the University of British Columbia demonstrated that dense neighborhoods encourage people to walk.) And it seems to me that from a public health perspective, we should seriously consider the notion that the environments we build--our cities and streets--can shape our behavior in ways that have direct implications for our waistlines and maybe even our lifelines.

Do You Know What You're Eating?

No. You don't. (pdf)

Research from the USDA suggests that we are generally wrong--by quite a bit--about what we're eating and how much. Researchers asked people to estimate how much food they eat in each nutritional category and then to keep records for 14 days of what they actually eat. There was a big gap.

Across age and gender, we underestimate the amount of grains we're consuming and wildly overestimate the amount of fruit. (We think we're eating about 2-1/2 times as much fruit as we actually are. And even the fruit we think we're eating would not be sufficient to meet federal nutrition guidelines.) Generally speaking, we're pretty accurate about how many veggies we get. We're consuming about half as much dairy as we think we are. And we're actually eating between 2/3 and 3/4 of the meat that we report.

The truth is, we eat about the right amount in the meat/protein/beans category. We eat a bit too much in the grains/cereal category. And we don't get enough of anything else.

Oh, there is one other category that we get enough of: "fats, oils, and sweets." The USDA does not recommend an amount, it only warns us to "use sparingly," a warning that is apparently going unheeded. Women consume about 50 percent more than they say they do and men consume about double what they report. And both genders are reporting that they eat more "fats, oils, and sweets" than they should.

It could be that the first obstacle to good nutrition is simply getting people to accurately assess their eating habits. It's awfully hard to combat obesity or encourage nine servings of fruits and veggies a day (the new federal guidelines for men) if we don't even know what we're eating in the first place. 

Walking the Walk

An article in today's Vancouver Sun (subscription required) reports on a new study showing that, in neighborhoods that are designed to make walking convenient, people do, in fact, walk more.  To wit:

People who lived the most walkable neighborhoods were 2.4 times as likely to walk for 30 minutes or more than those who lived in the least walkable communities.

The study's authors, led by UBC professor Lawrence Frank, defined walkable neighborhoods as having three core characteristics: they're compact, so that distances between destinations are shorter; their street grids connect, so that it's convenient to walk from place to place; and they have a good mixture of stores and homes, so that  people have places to walk to in their daily lives.  In such neighborhoods, people walk because it's a convenient form of transportation, not simply because it's good exercise.

The study has implications not only for transportation planning (places that encourage walking usually have less driving, lower per-capita spending on roads and fuel, etc.) but perhaps more importantly, for health.  A related study published last year showed that people who spend more time in their cars are more likely to be obese, compared with those who walk; and Canada's Heart and Stroke Foundation warned last week that residents of sprawling suburbs, who depend on cars for virtually every trip, are at higher risk of heart disease than are city-dwellers who are more likely to walk or bike from place to place.

But the UBC study, for me, raises one other core point: that our physical environments powerfully guide the choices that are seemingly made of our own free will.  Assuming that exercise is simply a matter of personal responsibility misses the point -- which is that a poorly-designed place makes unhealthy choices (e.g., driving everyhwere) virtually inevitable.  After all, the people who live in compact neighborhoods are really no different than the people who live in sprawling suburbs:  they're all making the most sensible transportation and exercise choices they can, based on the options available to them.

This point--that our environments shape our behavior--is obvious enough, but it tends to get lost in most public debates.  For the most part, public health campaigns around obesity have been designed to educate people about the benefits of exercise and a healthy diet.  But as the rising tide of obesity shows, those campaigns have been completely trumped by an unhealthy human environment--one that offers abundant and inexpensive junk foods, and few good opportunities to exercise. 

So perhaps the real public health campaign should start with designing neighborhoods where healthy choices are the easy ones, rather than the tough ones.

Killer Spuds II

The US government's diet guidelines are starting to catch up with reality. As I noted here, the official Food Guide Pyramid is disastrously wrong, misinforming people about what to eat. Well, the pyramid is about to get an overhaul, based on new diet guidelines just released, as the New York Times reports.

Of course, it would be simpler for the US Department of Agriculture simply to adopt the Healthy Eating Pyramid already introduced by Walter Willett of Harvard.

Fraser

British Columbia’s Fraser Basin Council just released its Sustainability Snapshot 2 (large pdf). The resulting report is a frustrating piece of work. It's rich with information but fails to tell a clear story that makes sense of it all.

So, here—in two points—is my distillation.

1. There's plenty of progress to be proud of!

• Air quality in the Fraser River Basin is not too bad, and it's mostly getting better.
• The basin--actually, the province overall--is 50 percent self-sufficient in food from just 5 percent of its land area.
• Between 1990 and 2002, the basin achieved a 24 percent reduction in per capita disposal of solid waste, largely thanks to rising recycling rates.
• Per-capita energy use also declined slightly, and per-capita domestic water use dipped by 4 percent between 1991 and 1999.
• Health, measured by lifespans, is improving throughout the basin, and is remarkably good in Vancouver.

2. But there are at least two glaring flaws in this made-in-Canada miracle: two facts that make the province look like a laggard not a leader, from a global and long-term view.

• The pace of emissions of climate-changing greenhouse is far too high. Plus, it's rising.
• The basin's endowment of species and ecosystems is in peril. One fifth of vertebrate species in the Fraser Basin are known to be endangered or threatened. Another share is probably at risk unbeknownst to us. And the number of species at risk appears to be rising.

To me, the prescription implicit in the Fraser Basin Council's description is this: make climate protection and biodiversity conservation the basin's highest priorities.

Best Foot Forward

Walking is supposed to be one of the healthiest activities around, but unfortunately, when you add cars into the mix, it can be lethal. The Surface Transportation Policy Project’s latest “Mean Streets” report finds that walking is the most dangerous mode of transportation, per mile, and is becoming more dangerous in some areas of the United States, particularly for certain segments of the population: African-Americans, for example, make up 19 percent of pedestrian deaths, even though they represent 12.7 percent of the total population.

And walking is declining as a form of transportation; the percentage of US commuters who walked to work decreased by 24.9 percent from 1990 to 2000.

The most dangerous cities for folks on foot include Memphis, Atlanta, and Houston, as well as several in Florida—in other words, cities where sprawling, low-density development and wide, arterial streets have the right of way. Cities that showed the greatest improvement in pedestrian safety, included Portland, Oregon—a leader at curbing low-density sprawl that is so inhospitable to pedestrians—and Salt Lake City, which is also relatively compact. Seattle didn’t fare as well, as the P-I points out, with pedestrians making up 18.5 percent of traffic fatalities in 2003, compared to the national rate of 11.3 percent.

The report called for greater investment in a transportation infrastructure that supports pedestrian safety and promotes walking. Even more key is encouraging cities to become more compact through policies such as Oregon’s land use laws, which have drawn a tight “girdle” around Portland’s development. Another intriguing idea is the new “shared streets” theory of traffic calming that—by limiting the separation of cars, pedestrians, cyclists, and reducing traffic controls—encourages streets to become self-regulating public spaces where pedestrians are on equal footing with slow-moving cars.

The Traffic is Murder Out There

In case you needed another reason to avoid being stuck in traffic--the L.A. Times today reports that the tiny particulates in highway exhaust are bad for your heart.

Researchers tracked healthy male police officers in their cars, and found that "exposure to particulate matter while inside their vehicles was correlated with irregular heart rhythm, elevated blood protein levels and other blood cell changes."  The effect is worst in stop-and-go traffic.

This report on the heels of another study  of European heart attack victims (reported here by the New Jersey Star-Ledger) which found that the more time people spend in traffic -- whether in a car, on a bike, or on public transit -- the greater their risk of suffering a heart attack.

So add heart attacks to the list of ways that driving kills.

Four More Years! Four More Years!

No, really.

A new study, mentioned in today's Seattle Times, found that sprawl is really bad for your health. To wit:

The study, which analyzed data on more than 8,600 Americans in 38 metropolitan areas, found that rates of arthritis, asthma, headaches and other complaints increased with the degree of sprawl. Living in the least sprawling areas, compared with living in the most, was like adding about four years to people's lives, the study found. (Emphasis added.)

The researchers said that sedentary lifestyles promoted by auto-dependent communities were at least partially to blame for shortened lifespans.

Winston Churchill was once reported to have said: "We shape our buildings and thereafter they shape us." I guess the same thing is true for our neighborhoods.

The Weight of Sprawl

University of British Columbia researcher Lawrence Frank has documented the sprawl-driving-obesity connection more rigorously than anyone else, with his massive new study of Atlanta. (Pdf of study here.)

The gist: The more you drive and the less you walk--and the more sprawling your neighborhood--the more likely you are to be obese.

Among other findings, as summarized by AP:

How much time a person spent driving had a greater impact on whether a person was obese than other factors such as income, education, gender or ethnicity.

Frank will soon release a similar study of King County, Washington. He hinted at some of the findings in a recent interview with Seattle P-I's columnist Bob Condor (who also pointed out that Washington's poor record on energy use shouldn't make us feel too superior to Georgia).

A growing body of research on obesity, activity, and sprawl is accumulating; other key contributors include the Robert Wood Johnson Foundation, and Richard Jackson of the CDC.

Weight Watch

This fascinating article in Harvard Magazine summarizes some of the latest research on obesity and inactivity—one of the most important health trends of the decade in Cascadia. (Check if you're too heavy on the calculator here.)

Some snippets to convince you to read it:

Two-thirds of American adults are overweight, and half of these are obese. . . [and] up to 80 percent of American adults should weigh less than they do. [Note: Obesity rates are slightly lower in the Northwest states and substantially lower in BC.]

The best single behavioral predictor of obesity in children and adults is the amount of television viewing.

Never in human experience has food been available in the staggering profusion seen in North America today. We are awash in edibles shipped in from around the planet; seasonality has largely disappeared. Food obtrudes itself constantly, seductively, into our lives—on sidewalks, in airplanes, at gas stations and movie theaters. Caloric intake is directly related to gross national product per capita.

We no longer live like hunter-gatherers, but we still have hunter-gatherer genes. Humans evolved in a state of ceaseless physical activity; they ate seasonally, since there was no other choice; and frequently there was nothing to eat at all. To get through hard winters and famines, the human body evolved a brilliant mechanism of storing energy in fat cells. The problem, for most of humanity's time on Earth, has been a scarcity of calories, not a surfeit. Our fat-storage mechanism worked beautifully until 50 to 100 years ago.

[Harvard professor of pediatrics] David Ludwig questions farm subsidies of "billions to the lowest-quality foods"—for example, grains like corn ("for corn sweeteners and animal feed to make Big Macs") and wheat ("refined carbohydrates.") Meanwhile, the government does not subsidize far healthier items like fruits, vegetables, beans, and nuts. "It's a perverse situation," he says. "The foods that are the worst for us have an artificially low price, and the best foods cost more.”

Subsidies to wasteful consumption that’s bad for our bodies, bank accounts, and planet, matched with obstacles to efficient, healthful alternatives--it sounds a lot like the Northwest’s land use patterns, energy policies, tax policies, auto insurance rules, and so on and so on.

The hopeful news is that solving any of these systemic problems helps to solve the others: better energy policies, for example, mean more compact communities mean more walking means less obesity means longer lives. A vicious circle, if inverted, can become a virtuous one.

A Wheely Good Idea

On Bike to Work Day, it's worth noting--as described in this excerpt from NEW's Seven Wonders--that the bicycle is the most energy-efficient form of travel. Pound for pound, a person on a bicycle expends less energy than any creature or machine covering the same distance. (A human walking spends about three times as much energy per pound; even a salmon swimming spends about twice as much.)

"While advertising sells cars and trucks as tools for the open road, they most often help us inhabit a small daily realm-"Errandsville"- defined by home, store, job, and school. Many of these trips are easily bikable -or walkable- even on roads designed without bicycles or pedestrians in mind. A bicyclist can easily cover a mile in four minutes.

"Short car trips are, naturally, the easiest to replace with a bike (or even walking) trip. Mile for mile, they are also the most polluting. Engines running cold, at typical urban speeds, produce four times the carbon monoxide and twice the volatile organic compounds (VOCs) as engines running hot. And at the end of a trip, smog-forming (and carcinogenic) VOCs continue to evaporate from an engine until it cools off, whether the engine's been running for five minutes or five hours."

As gas prices continue to skyrocket, we could also save a bundle by taking to two wheels more often. But we've got a long way to go: While about 20,000 more people in the US commuted by bike in 2000 than in 1990, the percentage is still very low -- 0.4 percent of all commuters.

Seek Transit

Here's yet another way of looking at the health benefits of reducing sprawl: denser cities with more transit ridership tend to have fewer traffic deaths. Take a look:

Fatalities (on the vertical axis) include deaths among pedestrians, transit riders, and automobile drivers and passengers.

The upshot is that U.S. cities with high levels of transit ridership--especially those with large rail systems--also tend to have low traffic fatalities. But cities that are more sprawling (and which tend to have bus-only transit systems) tend to have higher rates of traffic deaths.

(This graph was taken from Todd Litman's paper, "Comprehensive Evaluation of Rail Transit Benefits" available on the Victoria Transport Policy Institue website.)

Relieving Congestion

The city of London, which now imposes a £5 fee on cars entering the center city, has enjoyed an unexpectedly rapid fall in air pollution. Particulates (the ultra-fine soot that issues from car and truck tailpipes), carbon monoxide, and nitrous oxide are all down by 12 to 20 percent since the congestion fee was imposed. The fee, originally intended to reduce the crippling traffic congestion in downtown London, may be lightening the burden on Londoners' lungs as well as their streets.

The Dearth of Growth

The annual costs of add