Design Matters: When it comes to density, what can Canberra learn from Canada?

TT: In July, architect Murray Coleman gave his responses to the recent clear felling and future revitalisation of Northbourne Avenue corridor. One reader suggested we look at the minimum density requirements being considered in Ottawa. What did you find out, Murray?

MC: I started by reviewing the Federal Capital Design Competition won by Walter Burley Griffin and discovered the initial plan envisaged a city of only 25,000 people. The most surprising find was a reference in the competition rules to a 1910 planning conference in Britain, which included architect John Sulman’s detailed presentation anticipating our city growing to 100,000 but fobbing off further growth as a problem for later generations.

TT: But isn’t the issue more about density rather than just population size?

MC: If we were still a small city, density would be a non-issue. Walt’s plan for the Parliamentary Triangle and Civic has been well implemented and he developed major avenues intended for shared use by trams. With our population shooting past 400,000 and a 24-minute light rail journey from Gungahlin to Civic, and more to Woden, we have reached the geographical limit of light rail. It’s sensible to look at left-field solutions, such as the draft Ottawa regulation for minimum population density requirements, and apply them to Griffin’s avenues.

TT: It always seems strange to me that everyone seems to want to invent a new planning regime from scratch when good templates exist elsewhere. What might those regulations look like?

MC: Quite simply, Ottawa intends that, “intensification is directed to specific target areas … that have the potential to develop at moderate to high densities in a compact form”. Target areas include the CBD, avenues, town and group centres, while “compact form” limits creep into RZ1 areas. They propose minimum density targets for both housing and employment rather than minimum setbacks and maximum heights which combine to eat away at intensification and its potential for a safer, healthier social ambience.

TT: OK, so you are suggesting “fine-tuning” our urban density. What safeguards do they propose to avoid creating slums?

MC: Ottawa seeks to maximise employment, recreational and social opportunities within the transport corridors: for Canberra, owner-occupied housing opportunities should predominate, they should be suitable to downsize into, freeing up many under-utilised RZ1 family homes. And, yes, in Ottawa they do propose a nuanced range of density requirements for different parts of the city.

TT: Do you seriously think this intensification model could work for Canberra?

MC: It’s a chicken and egg situation: if light rail can be extended to and beyond each town and group centre, supported by a suitable network of minibuses or park-and-ride, then intensification along these corridors and centres would be a lasting benefit to all Canberrans: the alternative is miserably unending sprawl.

Tony Trobe is director of the local practice TT Architecture. Is there a planning or design issue in Canberra you’d like to discuss? Email tonytrobe@ttarchitecture.com.au.