Cascadia Scorecard Weblog

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.

Sprawling Alone

In Bowling Alone, Robert Putnam argues that the decline of social capital in the United States can be attributed partly to urban form. In other words, according to Putnam, sprawl is at least partly to blame for the present derth of bowling leagues. But is it really?

Putnam's arguments (summarized at the end of Chapter 12) are threefold.

1. "Sprawl takes time" and results in more time spent alone in a car and therefore less for civic engagement.
2. "Sprawl is associated with increasing social segregation" and that segregation has led to less community participation.
3. "Sprawl disrupts community 'boundedness'" and that physical fragmentation reduces societal involvement.

Although Putnam's claim--that sprawl erodes social capital--is widely referenced, my survey of the evidence makes me suspicious. My objections are threefold.

First, sprawl does not absorb more commuting time than does urbanization. Data from the National Household Transportation Survey shows astonishingly similar travel times across residential densities. Actually, residents of high densities spend the most time traveling. (Caveat: the NHTS is for "travel time" not specifically "commuting time," which Putnam is interested in, though commuting only accounts for about 1/4 of all personal trips.)

In fairness, high density households spend about 1/3 less time driving and proportionately more time walking, busing, or biking. So it's possible that urbanites use that extra 20 minutes per day to form social networks on public transit, but it seems equally possible that suburbanites form social networks while carpooling. In any case, no matter what the residential density, households sink roughly the same large chunk of time into commuting (74 to 79 minutes/day, most of which, even at high densities, is driving).

Putnam asserts a rough formula for measuring the effects of commuting: "each additional 10 minutes in daily commuting time cuts involvement in community affairs by 10 percent." Still, I can't see why sprawl is the culprit here. Instead, the culprit seems to be something like congestion, or perhaps the sheer physical size of cities (admittedly, related to sprawl), or perhaps even the population size of cities, which necessitates physical breadth. If sprawl is irrelevant here, it may help explain a point that Putnam apparently takes to be puzzling: that both surban and urban residents in big metro regions have less social capital than their small town counterparts.

Second, sprawl may be associated with social segregation, but the evidence that this erodes social capital is not conclusive, at least as far as I'm aware. Putnam does cite a couple of interesting studies here, but there are many more he bypasses. In a more comprehensive survey of the evidence, "The Effects of Sprawl on Neighborhood Social Ties," Lance Freeman finds that "the existing evidence is not conclusive" and that moreover very high densities may actually be corrosive of social capital.

Freeman's study goes on to find that residential density is unrelated to neighborhood social ties, but is strongly related to automobile dependence. As car dependence is generally a feature of sprawl, it may be that Freeman's study supports Putnam's conclusions. Still, both Freeman's survey of the literature and his data analysis should serve as a cautionary tale for imputing too much explanatory power to low residential density, which is often treated as the defining characteristic of sprawl.

Third, the importance of community "boundedness" is, as far as I can tell, based on only one study that's now more than 30 years old. Admittedly, it was something of a classic, but it's rather hard to imagine that the same cultural and geographic forces in play in 1972 are the same ones that now impede social capital. For just one example, city center populations have been growing again, rather than hollowing out as they were in the 1970s.

I'd like to see more evidence on this subject. It could be that Putnam is basically right and I'm just nitpicking, but for the time being I'm suspending judgment on the social effects of sprawl.

Seawall, See Wail

From today's Seattle P-I, here's yet another concrete way that global warming may affect the Northwest: rising sea levels may force the city of Seattle to reengineer its downtown seawall. 

Without a seawall, the businesses and roads along the Seattle waterfront simply wash away into Elliot bay. (Bummer.) The existing seawall is structurally unsound--it's partially made of wood, which is being eaten by marine invertebrates known as "gribbles"--and the city has already done a fair bit of the design work for rebuilding it. 

But a University of Washington climate science group now say that the proposed design, which assumes a .9 foot rise in sea levels over 75 years, may be too conservative.  The group predicts that sea levels may rise somewhere in the range of 1 to 2.8 feet.

To me, this story underscores two points that are worth keeping in mind.  First, there's a huge range of uncertainty in climate predictions; nobody, not even the most well-respected scientists, really knows what's going to happen.  And that makes planning really tough, and probably more expensive than you might otherwise think, or hope.  And second, there are lots of little ways in which rising global temperatures could affect our lives and our pocketbooks. Doomsday scenarios range from the unlikely to the comical (think "The Day After Tomorrow"), but that doesn't mean that the costs and consequences of global warming aren't very real.

Milestones on Mount Rainier

Even though it's August, and supposedly summer, I can't see Mount Rainier today because of the clouds. Still, it's worth remembering the mountain today because of two anniversaries--today and a week from today--in the history of Rainier: the first known successful climb and the first known climb by a woman.

115 years ago today, at 4:30 in the afternoon, Fay Fuller became the first woman to reach Columbia Crest, the summit of Mount Rainier. (Here's a short account of her climb, kept by the Tacoma Public Library, that makes a great read.) Unfortunately for Fuller, not only did she live in an era before gender equality, she climbed in an before the invention of synthetic fabrics, sunscreen, and the flashy ultra-light gear that is the hallmark of modern mountaineering.

According to the story:

Fay blackened her face with charcoal and wore goggles to modify the sun's glare. Her climbing outfit included heavy flannel underwear, a thick blue flannel bloomer suit, woolen hose, heavy calfskin boy's shoes with caulks, and a small straw hat. She later commented that her costume was assembled "at the time when bloomers were unknown and it was considered quite immodest."

A member of the group said that Fay refused assistance at some difficult spots. She is quoted as saying if she could not achieve the goal without their help she would not deserve to reach it.

Fuller's party reached the summit so late in the day that they were forced to spend the night on the summit in a cave hollowed out by sulphrous steam vents. Partly as a result of the prolonged exposure, they suffered terrible sun- and wind-burn and, in fact, spent five days recovering once they were back at Paradise.

According to Fay's account, despite the use of charcoal blackening "our lips, noses and almost all our faces were swollen out of proportion...for several days the pain was intense."

Rainier had first been climbed 20 years earlier (135 years ago on August 17) by Hazard Stevens and Philemon Van Trump, and the men fared no better than Fuller.

(Here's a short account by the Stevens-Van Trump climb by National Park Service.) There's actually some debate about whether Stevens and Van Trump were the first to summit Rainier. In Mountain Fever, Aubrey Haines claims that the first ascent happened as early as 1852. But Van Trump and Stevens have the first recorded summit and my understanding is that most knowledgeable people believe that they were the first to the top.

Stevens and Van Trump were guided by a local Yakama Indian named Sluiskin, who tried to prevent them from climbing the mountain because he believed it was suicidal.

According to another account, Sluiskin warned them:

"Your plan to climb Takhoma is all foolishness. At first the way is easy...[but] if you reach the great snowy dome, then a bitterly cold and furious tempest will sweep you off into space like a withered leaf."

Sluiskin was nearly right. Stevens and Van Trump were stranded on the summit toward evening with an approaching storm. Exhausted and unable to move, they huddled in a steam vent for the night,  probably saving them from death by exposure. The next day while returning to their camp near the top of the Paradise glacier Van Trump apparently suffered a "serious" injury (though I've never been able to figure out what it was). Nevertheless, both men survived the climb and became local celebrities as a result. 

Sluiskin's fear of the mountain may have been based partly on an old Indian legend. In an 1866 book, The Canoe and the Saddle, (strangely, sometimes called Saddle and Canoe) early Northwest visitor Theodore Winthrop recounts a legend told to him by Nisqually Indians. According to the story, local Indians believed that the summit of Rainier was home to a treasure trove of wealth. Driven by avarice and bravery, so the legend goes, one Indian managed to reach the summit, where he discovered riches beyond his imagination. But on the descent, the mountain unleashed a fury of storms so severe that he was eventually forced to abandon his treasure in order to save his life. He returned home a chastened man.

Unfortunately for enterprising mountaineers today, there is no treasure on the summit of Rainier. But then again, climbers today don't have to work nearly as hard to get there. Though the most popular route, from Paradise via Camp Muir, still demands 9,000 feet of elevation gain, glacier travel, and potentially dangerous weather, the climb can now be accomplished in a long weekend from the city.

In recent years, park service stats show that roughly 10,000 climbers attempt to reach the top, with about half making it. Despite the comparative luxury that climbers enjoy today--stoves, down sleeping bags, waterproof clothing, satellite-navigation systems, and emergency rescue--deaths and injuries are not uncommon. I suspect that the whiff of danger, together with the physical demands of the climb, are part of the allure that draws people to the Northwest's tallest mountain.

The view from the top is outstanding too. Or so I've heard. When I reached the summit in August, it was a day much like today, and all I saw were clouds blanketing the Northwest in every direction. 

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.

Sins of Emissions

Some news bits from the Oregon legislative session, which just ended:

As the Oregonian reports, the auto industry has been trying to head off an Oregon effort to adopt "clean-car" emissions standards by including language in the budget that would effectively prohibit DEQ from implementing the standards. (Clean-car standards, which Washington state just adopted, would reduce greenhouse gas emissions by some 30 percent and help drive the industry toward cleaner, more efficient design.) Governor Kulongoski has promised to counteract the move by using his veto power.

Meanwhile, the industry succeeded in effectively defeating a biofuels bill, which would have provided incentives for in-state production and use of renewable fuels such as ethanol  and biodiesel.

Automakers aren't exactly winning points for innovative thinking. From the Oregonian editorial:

The House Republicans who let this happen ought to have to spend the next election explaining why they would trade off Oregon jobs, Oregon agriculture and Oregon innovation all in a futile effort to extend a pollution tax credit and enable the auto industry to keep churning out cars that are less fuel efficient than those they made 20 years ago....

The auto industry has fought every advance -- seat belts, catalytic converters, air bags -- with this same argument about unacceptable costs. Every time its claims have been shown to be wildly inflated and wrong.

And in good news (mostly), the state did win a partial ban on toxic flame retardants known as PBDEs. Our study of PBDEs in Northwest women showed that the chemicals were found in relatively high levels in Oregonians; and a recent study of PBDEs in house dust found that Oregon samples had the highest levels of PBDEs.

More Urban Development Lessons from the North

As Parke's post mentioned, the Seattle P-I had another interesting article on the lessons Vancouver has to offer on urban development--making the city both an exciting and a family-friendly place to live. Tips include requiring developers to:

• create multi-bedroom apartments designed for families
• provide community centers, playgrounds, neighborhood schools, landscaping, and other public amenities
• design buildings that create a pedestrian-friendly and visually appealing streetscape--not just a barren street canyon. (Buildings on some streets are kept short to make them feel more homey.)

Seattle's mayor is in the midst of unveiling plans to create vibrant, dense urban centers by raising building heights, charging developers one fee of $1-2 per square foot to pay for parks and open space and another fee of $10 primarily to build low-income housing.

Because of differences in the nature of public planning and the current landscape of the two cities, Seattle probably won't ever become Vancouver, nor should it attempt to. But it has plenty to learn from its neighbor to the north.

Here are several other posts on the same topic.

Driving Towards Insurance Discounts

USA Today gives a nod to the concept of pay-as-you-drive (PAYD) car insurance in an article about how technology is changing insurance pricing. The article reviews pilot projects in Minnesota (Progressive’s Tripsense) and the U.K. (Norwich Union’s PAYD program).

Both programs are using GPS and wireless technology to track aspects of participants' driving--including distance, time of day, and where the vehicle is driven—that affect safety but aren't usually calculated into insurance premiums. Premiums are then priced accordingly. Not surprisingly, motorists are becoming more aware of the consequences of their driving behavior. And awareness, of course, is the first step toward change.

Here's an interesting twist: The monitoring seems to be getting people to drive more safely — not because they're afraid of repercussions, but because they're motivated to get bigger discounts. So instead of red light cams and state troopers with radar guns, maybe the way to get people to obey the rules of the road is to pay them to do it.

Research also indicates that the incentive of discounts will get people to drive less--up to 15 percent. But will drivers be willing to trade a little privacy for more cash? The USA Today writer thinks so.

It seems unlikely that any U.S. lawmaker would ever dare force car monitoring on us, but a decade from now, we might find ourselves buying into it, one person at a time.

Then, like those grocery cards, suddenly car monitors could seem as common and acceptable as house keys.

See a summary of PAYD programs here.

Vancouver, BC, in the News

Stanley Park in Vancouver, BC, has been named one of the world's ten best public spaces by the Project for Public Spaces. They write:

Within walking distance from downtown in a high-rise residential neighborhood with a population density similar to Manhattan, [Stanley Park] is easily accessible by foot, bike and car. Once there, you can take in some of the most spectacular natural settings of any public park in North America.

Vancouver also got a plug in today's P-I as a model for Seattle's plan to encourage greater urban density. NEW board member and former Vancouver City Councillor Gordon Price, quoted in the article, has done a fabulous job recording, both in prose and stunning photographs, the development of Vancouver as a "great place" in his electronic journal Price Tags. We have learned a lot from Gordon about how to build great urban neighborhoods.

In our parallel blog on the fundamentals of sustainability, we suggest that one of the key principles ought to be to Build Great Places. Vancouver, with Gordon's help, has clearly taken this idea to heart.

What do you think? Is urban design a mere luxury, or does it go to the core of how we function as a society? Does it determine how cohesive our communities are, or how lightly we tread on the environment?

And, if so, how should we build our great places? What does this mean for the choices we make today and the way we plan for tomorrow?

Please comment on this principle here.

Smart Grid: Energy Everyone Can Love

An excellent report from the researchers at Climate Solutions arguing for speedier implemention of Smart Grid technology in the Northwest's electric transmission system. Smart Grid refers to a host of technological updating that the current electrical system sorely needs. By integrating more advanced computers and digital processing, the electricity transmission can improve its efficiency and resilience.

In the event of disruption, such as a storm or even a terrorist attack, the Smart Grid would be capable of "healing itself" by redistributing power to where it's most needed. It will also allow operators to pinpoint interruptions more quickly so that they can fix the problem manually. Even better, by creating a more efficient system that wastes less and responds faster to changing conditions, the Smart Grid reduces the need for expensive new power plants and infrastructure. (In one case in Utah, a utility was able to save $4.3 million using new technology and was able to avoid building a new plant and transmission lines in environmentally sensitive areas.) And if that's not enough, a Smart Grid would allow true interface between distributed forms of eletricity generation like small-scale wind, solar, and fuel cell generators.

But enough blathering from me. The researchers at Climate Solutions have the low down: go read about it for yourself.

Postscript: In our latest book, NEW also argued for Smart Grid technology. It's an exciting reform for both environmental and security reasons and even more exciting because the Smart Grid is already on its way. Still, as the Climate Solutions report details, there are plenty of ways that the Northwest's leaders can hasten its arrival.