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Martin Laplante

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Thu, 10 Jan 2008

Why We Still Need Separation of Uses

An interesting column by Glen Murray of Navigator Resources, saying that separation of uses is a throwback remaining from industrial economies, where we all worked in factories. We don't have to keep so much abandoned industrial land available for when the jobs come back, he says. People work in the second bedroom of their 20th floor condo.

Some of it is on the right track and some is not. It's true that the policy of keeping plenty of cheap employment land that allows companies to sprawl as much as they want with 1-storey buildings and surface parking lots is probably no longer the most efficient way to use land. Keeping industrial land cheap is a competitive strategy against other municipalities: companies can locate wherever they get the best deal, so by making it easy for them to locate the municipality gains the jobs that indirectly pay the taxes. And in some backward tax systems, the distribution of where people live or work is driven by who can collect which tax, to the detriment of the average taxpayer.

Amalgamation of regions has somewhat reduced the need to artificially deflate the price of industrial land by keeping it plentiful, compared to when different cities and suburbs were competing with one another to attract jobs. Companies, manufacturing or not, are still one of the major motors of the economy. One-man operations in their condos still do not have the competitive advantage that companies get by gathering together a larger team and high-volume equipment. They still benefit from proximity to their clients and their suppliers, particularly in the service sector. So companies still need land, but the price of land is not a huge factor in deciding that they need to locate in your general region. With amalgamation, they can't easily play one municipality against another. Locate wherever you like in this region, the amalgamated cities can say, we're still getting the tax revenue. So it's safe now for cities to start becoming more thrifty with industrial land. Dear company, do you really need to use quite so much of it? Build more than one storey, bring the density up so that transit service can be attractive. Cities probably still need to keep some industrial land relatively cheap, implementing a supply stategy that you don't apply to housing or offices. That is one pragmatic reason to have separation of uses - so they are not competing for the same land. Separation of uses is not just about not having the factory fumes spewing into your back yard.

As I touched on before, a certain density of jobs is required to support a good transit service. And contrary to popular belief, the density of destinations such as jobs along the routes is a much bigger determinant of transit use than is residential density. In both cases, a certain minimum density is required to make transit pay for itself, but the density thresholds and increase in ridership with increased density are quite different for the two types of uses. In general terms, for employment the denser the better, but not so for homes. So a second reason why you need some separation of uses is to achieve job densities that are more difficult to achieve with mixed uses and that interfere with achieving optimal residential densities. You want a dense and expensive downtown where office towers go up and up. Stackable jobs, right on the transit line. Having jobs and housing competing for the same land makes the structure of land prices all wrong for both. For environmental reasons, highrises are a good solution for jobs and a poor solution for housing, for reasons I've explained elsewhere.

The third reason is also related to competition for land. Once you declare land to be mixed use, the market will tend to make it specialize into all one use or all the other. It would be an unlikely coincidence for the economic rent on the two types of uses to happen to be the same, unless there is an economic benefit to proximity. Unfortunately, there isn't much of one.

There are benefits, economic, social, and environmental, to having houses near houses and to having offices near offices. Kids can play with the neighbours and walk to school. Bicycle couriers reach your client in minutes. Where there is an economic benefit to the mixing of uses is in neighbourhood-serving retail, and that is where the mixed-use effort should be concentrated. The commute to work is responsible for only a quarter of all driving, and the best way to improve that is to have modest density of housing, very high densities of service jobs, and medium densities of other job types. But non-work destinations like retail and entertainment - every effort should be made to put those in walking or transit distance, or even conveniently between the houses and the transit stations. While we're modernizing urban planning for the realities of this century, let's not fixate on the single-breadwinner family of the 50's where you could try to minimize the home-job distance within your budget and where only daddy drove. Instead, encourage small local stores and schools and discourage large regional ones, and try to build real complete communities.


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