Saturday, November 29, 2008

Jane Jacobs Atlantic Yards Report Card #4: Appropriate Density? NO

This is evaluation item #4 (of 47) of the Jane Jacobs Atlantic Yards Report Card

Appropriate Density? NO


The absolutely incomparable density of Atlantic Yards is one of its most clearly controversial features. Jane Jacobs considered herself to be a proponent of density, describing in her book as dense the similarly dense neighborhoods of Brooklyn Heights and Greenwich Village, but she was not a proponent of a particular level of density which should be mathematically measured. Instead, she was a proponent of density at a level that would perform well, which would vary according to many other specific factors in play. She also called for gradual reductions of density when appropriate. Atlantic Yards is immensely more dense than, at least double, Manhattan and any area of New York City now or that might have been targets for such a density reduction at the time she wrote. High densities of Brooklyn Heights and Greenwich Village have remained similar to the time she wrote, though she favored those densities when the densities at the surrounding edges of those neighborhoods did not drop off. Since that time the edge of Brooklyn Heights has been built up which she would have favored. She mentions the Riverside Drive area in Manhattan with, twelve- and fourteen-story elevator apartments as having attained the highest density in the city at the time. For density performance purposes, she says that there shouldn’t be standardization of buildings and cites Greenwich Village as a model as managing to house people at densities ranging form 125 to 200 dwelling units per acre without standardization of buildings. Atlantic Yards is proposed to be substantially more dense 292 units per acre with buildings much taller than Riverside Drive. It will be 4 times the 51.2 units per acre density of Co-op City with its 26 story buildings. The recently planned community of Battery Park City will be about 153 units per acre (higher than the 147 units per acre in Manhattan’s densest areas) and is perhaps only about a hundred units currently. With an estimated residential population of 564 to 765 people per acre- in New York City units may average more, 2.8 residents- about the density would be many multiples of Manhattan’s average density of 104 people acre and the 292 units per acre would be about double the Manhattan’s highest density census districts at 147 units per acre. (Manhattan is the most densely populated county in the United States. Brooklyn’s has about 55 people per acre vs. Manhattan’s 104.6) More importantly Atlantic Yards does not meet Jacobs’ other prescriptions to achieve performing density, varied buildings built over time, on an interlacing of frequent streets that are added gradually. Jane Jacobs would almost certainly view Atlantic Yards as having a the kind of density that is too dense because, as she would say, it suppresses diversity rather than supporting it. It has been pointed out that if one departs from the North American continent one can find density comparable for that proposed for Atlantic Yards by going to the most densely populated neighborhood, Mongkok in Hong Kong, where density exceeds 640 inhabitants acre- This then means that people can live at such densities- But it doesn’t say why the precedent of this density should be set on this continent by awarding a monopoly without proper process to a low performing developer with poor design skills.

JJ Cites: [Also to be frank, I like dense cities best and care about them most. P.16 There must be a sufficiently dense concentration of people, for whatever purposes they may be there. This includes dense concentration on the case of people who are there because fo residence. P. 151. City dwellings have to be intensive in their use of the land too, for reasons that go much deeper than cost of land. On the other hand, this does not mean that everyone can or should be put into elevator apartment houses to live - - or not any one or two types of dwellings. That kind of solution kills diversity by obstructing it form another direction. P. 202 In Brooklyn, New York, the most generally admired, popular and upgrading neighborhood is Brooklyn Heights; it has much the highest density of dwellings in Brooklyn. . . . In Manhattan, the most fashionable pocket of the midtown East Side and the most fashionable pocket of Greenwich Village have dwelling densities in the same high range as th heart of Brooklyn Heights. But an interesting difference can be observed. In manhattan, very popular areas, characterized by high degrees of vitality and diversity surround these more fashionable pockets. In these surrounding popular areas, dwellings go still higher. In Brooklyn Heights, on the other hand, the fashionable pocket is surrounded by neighborhoods where dwelling unit densities drop off; vitality and popularity drop off too. P. 103 We cannot understand the effects of high or low densities if we assume that the relationship between concentration of people and production of diversity is a simple, straight mathematical affair. P.205 As an extreme example, no concentration of residence, however high, is “sufficient” to generate diversity in regimented projects because diversity has been regimented out in any case. And much the same effects, for different reasons, can occur in unplanned city neighborhoods, where buildings are too standardized or the blocks are too long, or there is no mixture of other primary uses besides dwellings. P. 205 Densities are too low, or too high, when they frustrate city diversity instead of abetting it. This flaw in performance is why they are too low or too high. . . Right amounts are right because of how they perform. P.209 A numerical answer means less than a functional answer (and unfortunately can even deafen the dogmatic to the truer and more subtle reports that come in from life.) . . . It follows, however, that densities can get too high if they reach a point at which, for any reason they begin to repress diversity instead of stimulate it. Precisely this can happen and it is the main point in considering how high is too high. The reason dwelling densities can begin repressing diversity if they get too high is this: At some point standardization of the buildings must set in. This is fatal, because great diversity in age and types of buildings has a direct, explicit connection with diversity of population, diversity of enterprise and diversity of scenes. P. 212 (I)n this process of packing dwellings on given acreages of land, it does not do to get too efficient, and it never did. There must be leeway for variety among buildings. P. 213 When Riverside Drive in Manhattan was built up, twelve- and fourteen-story elevator apartments were apparently the answer for maximum packing efficiency and with this particular standardization as a base the highest dwelling density belt in Manhattan has been produced. P. 213 It is not easy to reconcile high densities with great variety in buildings, yet it must be attempted. . .Greenwich Village is such a place. It manages to house people at densities ranging form 125 to 200 dwelling units per acre without standardization of buildings. . . .the reason Greenwich Village can reconcile such high densities with such great variety is that a high proportion of the land which is devoted to residences (called net residential acres) is covered with buildings. . . It is efficient a use of the land itself, that it permits a good deal of “inefficiency” in buildings. P.214 It is hardly possible to expect that many different types of dwellings or their buildings can be added at any one time. To think they can is be is wishful thinking. P. 216 The very process of increasing density gradually but continually can result in increasing variety too. And thus can permit high ultimate densities without standardization. P.216 High ground coverages, necessary as they are for variety at high densities, can become intolerable, particularly as they approach 70 percent. They become intolerable if the land is not interlaced with frequent streets. Long blocks with high ground coverages are oppressive. Frequent street, because they are openings between buildings, compensate for high coverage of ground off the streets. P. 217 It would be possible to bring down densities of dwelling units in those exceptional areas where dwelling densities are too high, and it could do this gradually to avoid cataclysmic mass upheavals of population. P. 333]


(For more on the subject of the scale of Atlantic Yards a subject closely linked to density, see Noticing New York’s post: Friday, September 26, 2008,Weighing Scale)

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