How should Christchurch expand?
What are the borders of Christchurch? Where does the city start and finish?
Is it the Green Frame, the Four Avenues, or further out - Belfast, Yaldhurst, Hornby, Halswell? Or is the city defined by the big shopping malls - Northwood, Westfields Riccarton, Eastgate, South City?
Those names sound like city gates. In medieval times, fortified walls kept cities secure. Old cities still have them.
Spaces define a city. Since the earliest times, humans have grouped together for security, welfare, and companionship. In planning its post-quake future, Christchurch needs to use space well. Otherwise, we will end up with a dysfunctional place, a jumble of separate enclaves, and no sense of unity.
By 2050, the world's population is expected to nudge 9 billion, up from 6.5 billion in 2010. Urban dwellers will number 7 billion, up from 3 billion. Not all cities will grow; population is declining in Japan and parts of Europe. What is clear is that cities will not stay the same.
"Cities are made for people, designed and occupied by people," British urban planner Tim Stonor, of Space Syntax, told an early-morning session at the Christchurch City Council offices.
"There is power in space."
Bad outcomes occur in rich cities, not just poor cities.
"Much of what we plan for doesn't happen; much of what does happen we don't plan for: sprawl, decay, pollution." Stonor describes the city as "a transaction machine: social, economic, cultural."
In a study of Christchurch's Green Frame, traffic patterns, and people movements, Stonor found busy spots in the central city, but also in other areas: Fitzgerald Ave, Lincoln Rd, Riccarton Rd, and Papanui Rd.
So is Christchurch's rebuild strategy on target? How should the city expand? The planned Green Frame will define the city's heart: a place for some businesses, shops, cafes and restaurants, cultural activities, a convention centre, and sports stadium. It will contain some old but mostly new buildings, with green spaces along the banks of the Avon.
The Green Frame is probably the best plan, but it is not the only one.
Imagine if the city centre was bigger. Imagine high-rise offices and hotels lining Riccarton Rd, Papanui Rd, Lincoln Rd, and the main avenues. Imagine the extent of damage after a big earthquake! Perhaps it is just as well the city centre is as compact as it is.
I suspect most Christchurch people would prefer a lower density, low-rise, green city. People still want "a city in a garden".
That tag, CBD (Central Business District) sounds boring. What else could we call it? Downtown? Old Town Christchurch?
Whatever we call it, let's keep the centre compact, but plan for growth in other areas. The Green Frame is only part of the future. We should not forget existing suburbs; they are Christchurch, too.
We can still have a polycentric city, with mixed-use areas encompassing businesses, industry, entertainment, retail, sports, and housing - and eco-villages and apartments, not just conventional subdivisions. However, long-term growth needs a vision and a plan, not just laissez faire or a business-as-usual, let-the-market-decide approach.
Getting locked into small-town mentality is a danger. Christchurch is New Zealand's second-largest city. The old bus exchange, for example, was too small; the same is likely to occur with a new interchange in the central city. The city needs a major transport hub, ideally on the old railway station site in Moorhouse Ave. It also needs hubs to the north and west.
Mobility matters. "Movement is the lifeblood of the city," says Stonor. "Is congestion really the goal of advanced civilisations?"
He compares two cities: Paris, with people-friendly streets, and buildings opening to streets like the Champs Elysee; and a city in Saudi Arabia with fast-moving highways, empty footpaths and buildings facing away from the streets.
For businesses, the lesson is simple: "Go where the people are and the competitors are." Stonor adds that criminals exploit poor planning of space.
If well-connected streets help businesses, should Christchurch retain its one-way system? Traffic engineers and the council appear to be in no hurry to change it.
Nevertheless, the need for better connections is overwhelming. Stonor observes that grids are difficult. A mix of quiet and busy streets works well.
Car yards and warehouses dominate many of Christchurch's wide avenues, with the exception of Hagley Park.
Approaching the city along its main arteries is hardly a delightful experience; the streetscape can be unremittingly ugly. Those wide avenues could be much more attractive, like Parisian boulevards. Imagine trams running down the centre, as they do in Europe.
That is unlikely. We could at least have better spaces for cyclists and pedestrians, combined with attractive landscaping and architecture.
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