D - Density


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Slide 1

“The art and science [of urban design] is so arranging streets and public spaces so that private land may be put to best use.” 1912 Masterplan of St Louis D is For Density: City as a System – It’s Purpose, interconnections and Physical Elements

Slide 2

Density is a simple concept. Mathematically: People per area (sq.mi/acre) And Density is not necessarily “urban” – but those two words have become conflated. There is good density and bad density…or better yet density has pros and cons: PROS Reduced energy use per capita Higher income (cities vs countryside) Greater amenity afforded via commonwealth (tax base) Reduced infrastructure cost per capita Increased “pursuit of happiness” (range of opportunity) Collaboration (idea combustion) Preserved nearby agricultural land (resilience) CONS CRIME (at least perception) COMMUNICABLE DISEASE Source: Joe Minicozzi

Slide 3

A problem of design rather than of city or density. The key as urbanists (professionally) and as a society is to maximize the positive benefits of urbanism while minimizing, reducing or eradicating the negative. Copenhagen is often cited as a model because it minimizes the negative outputs, it is a very healthy and safe city. Bloomberg (NYC) has specifically set a goal of his staff to increase life expectancy (it is now two full years higher (80.9) than average American) When factoring traffic injuries/fatalities, urban areas are safer than auto-dependent sprawl (Lucy).

Slide 4

Density also synonymous with overcrowding, hence its prevailing stigma. Though, problems with tenement housing, slums, of 20th c. was a problem of industrialization, not of cities Poor holistic system design (including economic and political – lack of labor standards, poor infrastructure, sanitation…) Diminishing Returns – benefits of density taper off after a certain point (system ceases becoming more efficient)

Slide 5

There is a tendency to over simplify or overly abstract notion of density merely to tall buildings. Presence of tall buildings doesn’t necessarily indicate density or economic vibrancy. Merely supply of building space, but not necessarily filling that space. Is it a complete place? Are all of your daily needs nearby? Or a glorified office park that empties out at night? L’Eixample: 140/ac. Manhattan: 110/ac. Dallas: 5.5/ac. (only a few census tracts over 40)

Slide 6

Supply vs. Demand Density is result of Desirability, Demand. Job of Real Estate market to match Supply with Demand. We’re very poor at it these days. To understand cities and density we have to understand where Demand comes from

Slide 7

In The Economy of Cities, Jane Jacobs, argued that it was trade routes forming the impetus of cities rather than agricultural advancements (conventional wisdom). Both right in that they advanced clustering, but it doesn’t get to the heart of the explanation. What is deeper driver? And what unifies demand for clustering then and now? Why did the first two families agglomerate?

Slide 8

The fundamental need for improved quality of life. Maslow’s Hierarchy of Needs, an emotional impulse. The first cities, Catal Huyuk, were about safety, security, and shelter…the most basic of needs. “Cities could persist for thousands of years only if their advantages offset their disadvantages.” O’Flaherty

Slide 9

Rankings for the “Most Livable Cities” measure those places where the greatest percentage of the population have: Opportunity – the pursuit of happiness, and Security – of basic needs. World cities (Moscow, London, Paris, New York, Shanghai) vs. Livable Cities (Copenhagen, Melbourne, Vancouver, Zurich) Higher peak experiences, but lower baseline.

Slide 10

EMOTION. Our need for social and economic exchange (goods, services, ideas, laughs, genes, etc.) is what improves Quality of Life. Cities are machines of social and economic exchange. It’s why they’ve been around as long as civilization. You could argue that it was cities that civilized, not unlike socializing bad dogs. And Cities are physical representations of economies… Then it is logical to apply emotional wants & needs to cities as a driver of the resultant urban form Economics are driven by the exchange of needs, wants, demands of emotion…

Slide 11

Exchange or Meeting points, Intersections, are the Atom of the City, its most basic building block. When a city grows, its intersections expand into a network. It becomes a complex system. Each intersection has its own character, but also participates in hierarchy of larger organizing elements: neighborhood, city, metropolitan area) The infrastructure network forms the bones of which housing and commercial organize around.

Slide 12

Only recently has our infrastructure network no longer served the primary purpose of City: social and economic exchange. It was no longer about maximizing highest and best utilization of private land or quality of life Now serves another master. Strictly about moving cars. The traffic engineer’s standards and formulae trump all other concerns (along with political desire to spend federal and state money locally for temporary gain…)

Slide 13

The invisible City manifested by Desire Lines: our social and economic networks are invisible, but the infrastructure we build becomes the physical platform for them. There is a disconnect between how we build cities today and our underlying needs. Though in many ways, there always has been. Today, there is no longer an underlying logic. The key is shaping our cities to our needs as quickly as possible.

Slide 14

Why are skylines roughly conical? Supply met Demand. Demand, and in turn most supply, was created at points of highest degree of interconnectivity, or “reach.” Champs Elysees, most connected place in Paris (highest real estate value), but the train stations and highways remain at periphery. However, height restrictions limit supply, inflating price in order to preserve character.

Slide 15

Why are skylines roughly conical? Dallas built its tallest buildings (60’s to 80’s) the same time it was systematically sapping demand from downtown through the construction of inner-city highways. No longer a hierarchy of more (centers) and less connected places (edge). The highways disconnect more than they connect.

Slide 16

WalkScore heatmaps measure propinquity, proximity of wants and needs, goods and services The outward construction created its own economy, its own growth. But an economy of cities built entirely on outward growth is impossible to sustain. Building an infrastructure of disconnection rather than as a platform of connectivity, of social and economic exchange creates “Anti-City,” where all places are equal. No inherent logic or order. Everywhere competes with everywhere else and there is little cooperation or relationship, particularly in relationship with proximity. It’s a race to the bottom, the systematic devaluing of places rather than improvement.

Slide 17

Real Estate market adapted to the new reality: sprawl. Mantra shifted from “location, location, location” to “build it and they will come.” Our gathering spaces have been disconnected and internalized. It becomes inherently cannibalistic, as there is no built-in resilience of “complete communities” and neighborhoods.

Slide 18

Yet logic of cities remained, Traffic = Value. But the traffic was no longer the same… We replaced “High Roads” with Highways. Sociopetal with Sociofugal. Gathering places with repellent spaces. We added the most supply along highways, which turned out to be undesirable. The highways divide more than they connect, as global infrastructure often does. The city atomized into its individual components, became Anti-city. We have to be connected both locally and globally without letting global infrastructure disconnect local connectivity.

Slide 19

It often takes a generation for a place to find its true value. Lag time of about 20 years… It’s why lenders want their returns in 7 years… fundamentally broken system. No lasting value, desirability. QUESTION/CONCLUSION: “if density is about desirability and if cities, as a machine for social and economic exchange to improve quality of life, must be more advantageous than disadvantageous, what are the limiting factors in Dallas?