Suburb: Planning Politics and the Public Interest is a scholarly book about planning politics in Montgomery County, a (mostly) affluent suburb of Washington, D.C. The book contains chapters on redevelopment of inner ring, transit-friendly areas such as Friendship Heights and Silver Spring, but also discusses outer suburbs and the county’s agricultural areas.
From my perspective, the most interesting section of the book was the chapter on Friendship Heights and Bethesda, two inner-ring areas near subway stops. When landowners proposed to redevelop these areas, the planning staff actually downzoned them (p. 56)- and NIMBYs fought the planning board, arguing that even more downzoning was necessary to prevent unwelcome development.
These downzoning decisions were based on the staff’s “transportation capacity analysis”- the idea that an area’s roads can only support X feet of additional development. For example, Hanson writes that Friendship Heights “could support only 1.6 million square feet of additional development.” (p. 62). Similarly, he writes that Bethesda’s “roads and transit could handle only 12 million square feet of new development at an acceptable level of service.” (p. 75)
Thus, planning staff artificially limited development based on “level of service “(LOS) . “Level of service” is a concept used to grade automobile traffic; where traffic is free-flowing the LOS is A. But the idea that development is inappropriate in low-LOS places seems a bit inconsistent with my experience. Bethesda and Friendship Heights zip codes have about 5000-10,000 people per square mile; many places with far more density seem to function adequately. For example, Kew Gardens Hills in central Queens has 27,000 people per square mile, relies on bus service, and yet seems to be a moderately popular area.
Moreover, the use of LOS to cap density has a variety of other negative effects. First, places with free-flowing traffic tend to be dangerous for pedestrians; for example, if an arterial is at LOS A, cars travel over 35 mph and thus create a high risk of injury or death to walkers. Second, when people and jobs are excluded from transit-friendly places such as Bethesda, they do not disappear. Instead, they migrate elsewhere- often to more car-dependent places, increasing regional auto traffic. Third, policies that limit housing anywhere reduce the regional supply of housing, thus affecting regionwide housing costs.
At any rate, this book’s value for market urbanists is to show what planners really do. Sprawl supporters often paint zoning as a reflection of the market, and planners as pro-density ideologues. But in fact, planners often seek to split the difference between developers who seek to create housing and jobs, and nearby homeowners who want less of both.