Here's something to ponder. Below are two charts comparing certain aspects of several cities.
The first is a chart prepared to compare the 'sustainability' in 2005 of twenty different US cities -- in other words, the level of wetness adopted by city planners, and the extent to which land-use restrictions are imposed and property rights ignored. (The methodology is outlined here. The rankings for 2006 are here.)
The second chart (below) compares the affordability of several of the world's cities, with 'severely unaffordable' cities at the top and affordable cities at the bottom. (Affordability is given as a multiplier of that city's average income.)
Just by comparing the two charts you'll see an obvious trend: cities ranking highly in one chart generally rank rather highly in the other chart as well. In other words, cities that are highly 'sustainable' also tend to be highly unaffordable -- no surprise when 'sustainability' usually takes the form of restricting the supply of housing in some way. Examining the figures for the top ten 'sustainable' cities only confirms this:
1. Portland (29th Most Unaffordable US City, with a Multiplier of 4.2 times the average income, making it seriously unaffordable.)
2. San Francisco (5th Most Unaffordable US City, with a Multiplier of 9.3 times the average income, making it severely unaffordable!)
3. Seattle (18th, 5.3 - severely unaffordable)
4. Chicago (23rd, 4.9 - seriously unaffordable)
5. Oakland (not measured)
6. New York City (7th, 7.9 - severely unaffordable)
7. Boston (15th, 6.1, severely unaffordable)
8. Philadelpia ( 32nd, 3.9, moderately unaffordable)
9. Denver ( 19th, 4.0, moderately unaffordable)
10. Minneapolis (30th, 3.5, moderately unaffordable)
So many of the the 'most sustainable' cities are also amongst the most unaffordable. Being dripping wet costs money, and it seems that first-home buyers are the ones forced to meet that cost the most. Turns out too that the 'least sustainable' cities by the wetness standard generally rank amongst the less severely unaffordable places in which to buy a home:
40. Tulsa (8th most affordable city in the US, 2.6 - affordable)
41. Arlington (not measured)
42. Nashville (26th most affordable, 3.3 - moderately unaffordable)
43. Detroit (24th most affordable, 3.1 - moderately unaffordable)
44. Memphis (26th, 3.2 - moderately unaffordable)
45. Indianapolis (4th most affordable, 2.4 - affordable)
46. Fort Worth (not measured)
47. Mesa (not measured)
48. Virginia Beach (xxth, 4.0 - moderately unaffordable)
49. Oklahoma City (10th most affordable, 2.7 - affordable)
50. Columbus (20th most affordable, 2.9 - affordable)
Only Kansas City (18th) and the Lone Star State's Austin (14th) register both in the top-twenty dripping wetUS cities and the list of US cities that are affordable. Clearly there are other factors at play as well, but denying there is some correlation between restricting the supply of land and of development, and the resulting cost of supplying land and housing is like trying to deny the passing of the seasons.
You can argue all you like about the benefits of 'sustainability,' but the extent that 'sustainability' is imposed on cities by restricting the supply of land and housing appears to be the extent to which that city is made unaffordable to first-home buyers.
It would be interesting to try such a correlation across New Zealand's cities, except for two things: the first is that all New Zealand cities have essentially the same restrictive land-use policies so there's little variability to measure; the second is that, as a consequence of those restrictive land-use policies, all major New Zealand cities rank in the 'severely unaffordable' category.
LINKS: 2006 SustainLane US City rankings - SustainLane
2nd annual international housing affordability survey, 2006 - report at Demographia.com
'NZ housing affordability in crisis' says report - Not PC (Jan, 2006)
TAGS: Urban_Design, RMA