Sustainable Land Use Planning

October 20, 2015

Overview

*Sprawl - What is it & Why?

*Consequences

*Understanding Density

Sprawl

Coming to a neighborhood near you.

Source: http://www.digitaltrends.com/photography/how-one-dslr-pioneer-shoots-for-the-big-screen-with-a-little-cam/

Source: http://www.fastcodesign.com/3028661/slicker-city/urban-sprawl-get-fat-stay-poor-and-die-in-car-crashes

"Sprawl is like pornography- hard to define but you know it when you see it."

- David Rusk*, Urban Sprawl: a Comprehensive Reference Guide

*Rusk's method: The ration of growth of urbanized population to the growth of urbanized land.

Source: http://www.smartgrowthamerica.org/documents/measuring-sprawl-2014.pdf

Source: http://www.smartgrowthamerica.org/documents/measuring-sprawl-2014.pdf

How did they measure sprawl?

• Development Density
• Land Use Mix
• Activity Centering
• Street Accessibility

Each of the four points includes multiple sub-indicators.

Eight Dimensions of Sprawl

• Density
• Continuity
• Concentration
• Clustering

• Centrality
• Nuclearity
• Mixed Uses
• Proximity

Source: http://www.tandfonline.com/doi/pdf/10.1080/10511482.2001.9521426

Density

Density is the average number of residential units per square mile of developable land in an urban area.

Continuity

Continuinty is the degree to which developable land has been built upon at urban densities in an unbroken fashion.

Concentration

Concentration is the degree to which development is located disproportionately in relatively few square miles of the total UA rather than spread evenly throughout.

Clustering

Clustering is the degree to which development has been tightly bunched to minimize the amount of land in each square mile of developable land occupied by residential or nonresidential uses. 

Centrality

Centrality is the degree to which residential or nonresidential development (or both) is located close to the central business district (CBD) of an urban area

Nuclearity

Nuclearity is the extent to which an urban area is characterized by a mononuclear (as opposed to polynuclear) pattern of development.

Mixed Uses

Mixed uses means the degree to which two different land uses commonly exist within the same small area, and this is common across the UA.

Proximity

Proximity is the degree to which different land uses are close to each other across a UA.

How did we get here?

Historically, transportation and housing policy have had big impact on urban form.

The Times They Are A Changin', Especially Post-WWII

• Population growth spurred by baby boom and post-war immigration
• Federal highway construction (National Interstate and Highways Defense Act)
• Urban renewal building replaces dense neighborhoods with large scale road and highway projects
• Federal housing administration and VA subsidize mortgages for single family homes
• Local zoning laws begin to segregate uses by use type

Sprawl has consequences.

Our challenge today is to manage tradeoffs between today's needs and tomorrow's capacity.

More GHG Emissions

Less Return on Investment

Source: http://www.planetizen.com/node/53922

So what does sustainable density look like?

http://persquaremile.com/2012/08/08/if-the-worlds-population-lived-like/

Source: https://placesjournal.org/article/building-hyperdensity-and-civic-delight/

Source: https://placesjournal.org/article/building-hyperdensity-and-civic-delight/

Source: https://placesjournal.org/article/building-hyperdensity-and-civic-delight/

Floor-Area Ratio (FAR)

Source: http://densityatlas.org/measuring/metrics.shtml

So what planning tools exist to manage for sustainable densities?

• Comprehensive Planning
• Flexible & Form-Based Zoning
• Land Conservation to Constrain Growth
• Incentives for density, mixed use, and walkability
• Smart allocation of capital infrastructure funds