When neighborhoods are allowed to plan and zone without considering the regionwide interest in increasing housing stock, scarcity results.

A newly popular urban planning buzzword is "community-based planning." For example, the New York City Department of City Planning's website states that "community-based planning is essential to the city's vitality" because "people who are close to neighborhood issues can clearly identify community needs and advocate passionately for local concerns." The implicit assumption of this conventional wisdom is that when neighborhoods are given absolute power over planning, their wishes create no harmful externalities affecting the city as a whole. Some scholars argue, by contrast, that land use planning should be conducted on a citywide or even a statewide basis, because existing residents of a neighborhood may want things that are bad for the city as a whole (for example, exclusionary zoning that limits housing supply and raises housing prices).*
Neighborhood activists in Brooklyn's Bushwick neighborhood recently created their own community plan. Which view does the Bushwick plan support?
The transportation portion of the Bushwick plan seems to be consistent with the citywide interest in reducing automobile pollution and car crashes. For example, the plan proposes traffic calming along several major streets (p. 68), extension of the city's bike lane network (id.) and increased bicycle parking near train stations (id.). In addition, the plan supports improved transit service (id. at 69-70) as well as more seating and shelters at neighborhood bus stops (id. at 70).
Bushwick is next door to gentrified Williamsburg, and people priced out of Williamsburg are starting to move to Bushwick. As a result, rents are rising more rapidly in Bushwick than in the city as a whole. So, naturally, the plan emphasizes the importance of affordable housing (p. 17). As one might expect in a low-income neighborhood, the plan supports redeveloping publicly-owned sites as "affordable" (English translation: subsidized low-income) housing. The plan even suggests that the city "consider higher-density zoning on publicly owned sites" (p. 20). Thus, the plan seems consistent with the citywide interest in housing the poor.
The plan also seems to endorse mixed-use development. It notes that in some neighborhoods, "commercial overlay" zoning allows ground-floor commercial use below residential buildings (p. 26-7). But in Bushwick, many blocks lack such commercial overlays, which means that "existing buildings cannot create new storefront space" (p. 27). The plan describes this zoning as "obsolete," implying that residential buildings should be allowed to have ground-floor retail.
But what the plan gives with one hand it takes with others. Generally, the plan's guiding principles include "no more total units than the No-Action Scenario would produce, unless those additional units are deeply affordable" (p. 30). In other words, no new housing should be built unless it is for very poor people or is allowed by current zoning. In fact, the plan suggests that existing zoning allows too much housing, stating that current zoning is "overly lenient" (p. 25).
The plan complains that the neighborhood's existing zoning does not have height limits, while in Brooklyn's gentrified areas the city has created new zoning districts "with strictly defined height limits and density appropriate to the context of the existing buildings" (Id.). In other words, the plan says: rich people got to downzone so we should do the same. Of course, if everyone downzones, the city's housing supply falls even further behind demand, and rents go even higher.
The plan excuses these policies by pointing to the great God of Context. It writes that in the absence of downzoning, there might be an "out-of-scale tower" or development that is not "appropriate to the context" (p. 265). This attitude illustrates the Myth of the Immaculately Concieved Neighborhood: the idea that no housing has been or ever should be different from its neighbors, and that the neighborhood status quo is eternal. But if "out of context" housing was disallowed, no housing in Bushwick or anywhere else would have ever been built. The very first farmhouse in Bushwick was no doubt "out of context" from the surrounding landscape of forests. When Bushwick began to urbanize and rowhouses were built, the first rowhouses were probably "out of context" with the surrounding landscape of single-family homes. And when the first apartment building in Bushwick was built, that apartment building was no doubt "out of context" with its rowhouse neighbors. So the plan’s obsession with context is nonsensical.
Furthermore, there are plenty of American neighborhoods where different scales of housing coexist with each other. On my own block in Manhattan, a 20-story building coexists amicably with two- and three-story townhouses.
The plan also seeks to prevent any rezoning of industrial areas (p. 30) because "the manufacturing industry [is] a defining neighborhood feature" (p. 41)—as if this was still the 1950s, when manufacturing was a major source of blue-collar employment. But of about 1400 jobs available in Bushwick, only 56 are in manufacturing (p. 41), or about 4 percent. So jobs don’t really justify single-use zoning in manufacturing areas.
The plan also writes that if other businesses outbid manufacturing for scarce land, “a growing population and aging infrastructure [will] exacerbate congestion on major throughways and impact local businesses.” (p. 41). This sentence seems to me to mean that manufacturing is not really a defining feature of the neighborhood—just an excuse to zone out housing for human beings. Of course, a growing population means more businesses to serve the growing population, not fewer. So I don't think anyone can rationally suggest that rezoning manufacturing areas is bad for the local economy. Maybe the plan is suggesting that population should be limited to reduce congestion. But this is of course a beggar thy neighbor argument: if people can't move to Bushwick because of congestion, they will move somewhere else and create congestion there.
So what happens if new housing doesn't get built? If the housing supply in Brooklyn's richer areas is insufficient to meet demand, people priced out of those neighborhoods will flood into poorer areas like Bushwick. So if Bushwick also limits housing supply, people priced out of Bushwick will move to even poorer areas like Brownsville or East New York, causing higher demand, higher rents and gentrification in those neighborhoods. The plan complains about displacement and unaffordability, yet endorses anti-housing policies that are likely to exacerbate these problems.
In sum, the Bushwick plan is an excellent example of what happens when neighborhoods are allowed to plan in the interests of local activists: they may try to lock out everyone else, creating a regionwide housing shortage. And that's why community-based planning is anything but "essential."
*I realize that just as some die-hards continue to deny the reality of climate change, others continue to deny that housing supply has anything to do with housing prices. I refer these people to both my own work and to Vicki Been's work, as well as to those sources cited in those works.

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