Tuesday, November 30, 2004

Sprawl and Health

"Is Sprawl Unhealthy" ask Alexia C. Kelly-Schwartz, Jean Stockard, Scott Doyle and Marc Schlossberg (all of U. of Oregon) in the latest Journal of Planning Education and Research. They write that, "... the results indicate that even with strong controls for individual variables, residents of areas with more highly accessible and gridded street networks have higher health ratings. At the same time, residents of more densely populated urban areas have lower health, net of individual-level measures. Measures of sprawl have no significant relationship to frequency of walking, body mass index, or diagnosis of various chronic diseases. However, among those with chronic conditions, including hypertension, diabetes, and lung disease, those who live in areas with more highly connected street networks have higher rated health."

Leaving aside any quibbles about methodology, data or inference, what are we to do with such findings? The authors conclude that, "... some aspects of compact development, such as street connectivity, [promote] better health, and other aspects, such as high density, potentially [detract] from better health."

Neither planners nor developers (nor their clients and customers) have shown any interest in low density development sited on tightly gridded street networks. There are trade-offs in production and in consumption that are reconciled in the real world -- often best reconciled in the markeplace.

Planners, policy makers and politicians should do (very) few things and do them well. There is very little for them to do in the realm of health and the physical environment. They will, of course, forever be on the lookout for simple associations that might expand their ambit.

Just last week the WSJ reported that, "CDC Study Overstated Obesity as a Cause of Death ... Admitting Errors, Agency Expects to Revise Findings; Big Health Concerns Remain ..." Of course.