Fix Climate 4: How Sprawl Drives A Third of All Emissions

Land use policy that encourages compact development should be a cornerstone of all municipal climate action.

We’ve recently argued that suburban sprawl is eating up more and more of city budgets.

Sprawl, it turns out, is equally hard on our carbon budgets.

As we will see, land use policy that encourages compact development is one of the most impactful actions that cities can take to get carbon emissions under control.

A third of all emissions

Recent work by RMI, a non-profit energy research organization, reports that a third of global emissions are linked to urban sprawl.

Sprawl creates emissions in three main ways.

• People travel more by car, burning more fuel or consuming more electricity (which in turn can be generated by burning fossil fuels).

• Significant carbon emissions go into creating the roads and other infrastructure required for urban expansion.

• In converting farmland to new subdivisions, we experience a loss of natural carbon sinks.

RMI reports that sprawling cities have 2.5 times higher emissions per capita compared to their compact counterparts.

No different in Canada

This story applies equally to Canadian cities.

One study of Toronto reported significant differences in per capita carbon emissions based on where people live, from 3 tonnes of carbon dioxide equivalents (C02e) per year for people in the core to 13 tonnes for people in low-density suburbs.

The recent work of the Task Force on Housing and Climate looked at the climate impacts of building the 5.8 million new homes that the Canadian Mortgage and Housing Corporation says we need to restore affordability.

They compared building those homes under a business-as-usual model (i.e., the way we had built homes over the previous 10 years) versus a targeted infill model.

The targeted infill model would produce fewer carbon emissions. Infill would prevent us from releasing 4.5 megatonnes of C02e emissions annually compared to what would be released under the business-as-usual scenario.

Cities have the policy levers

Land use decision matters.

Creating new homes and housing people in existing neighbourhoods has a significantly lower carbon footprint than in new suburban developments.

Fewer vehicle miles travelled. Less carbon embedded in roads. Less loss of natural carbon sinks.

(Materials and building codes have a large impact also, but that’s a story for another day).

Cities have the policy levers required to prioritize infill building over sprawl.

Last week, we described the BuildingIN program, of which CitySHAPES is a partner.

While infill has an environmental (and fiscal and quality of life) advantage over sprawl, infill at scale will not happen on its own. The business case is just not there for the private developers who build more than 90% of new homes in Canada.

BuildingIN helps municipalities achieve infill at scale, through a program of complete community redevelopment. That program provides households of all sizes with options for living in compact neighbourhoods that don’t require people to own a car. The program also provides builders with the profit potential they can currently achieve with new sub-divisions.

Housing is a major challenge for cities in reducing emissions. Infill is major part of the solution to meeting that housing challenge in an environmentally friendly manner.