In the for-and-against debate surrounding compact cities and their impact on housing affordability, Auckland and its Unitary Plan stand out as an oddity. 

The compact city term lacks a clear definition, but if you look for commonalities across the literature and practical examples of this urban form, two policy outcomes repeat themselves: urban growth restrictions and higher population densities. 

Advocates of Smart Growth and New Urbanism, the cheerleaders of compact cities, argue that if you achieve these two outcomes you will pave the way for the other desirable outcomes that this urban form seeks to achieve. 

These include higher public transit usage, fewer cars on the road, less pollution, greater social equity, and improved health outcomes to name but a few. In short, a more sustainable existence for urban dwellers, and if you want the above you have to accept strict regulation and tight land usage controls. 

Yet it is this compact city orthodoxy that the Auckland Council, through its Unitary Plan, is looking to diverge from, at least on paper. 

The city's planners argue they are in fact deregulating Auckland's property market by easing the height restrictions that are in place in many neighbourhoods, and even then, only along transport corridors, not entire suburbs. 

That should allow developers more flexibility in the type of housing they provide to the market (presumably apartments and terraced housing), satisfying the pent-up demand held by people who want to live in more compact forms but have been prevented from doing so by these rules. 

Secondly, Auckland's long standing metropolitan urban limit (MUL), which has constrained the expansion of the outer city suburbs for decades, is set to be replaced with a rural urban boundary (RUB). This new demarcation includes a vast tranche of new land big enough to accommodate 90,000 homes that will be released for development progressively until 2040. 

Seen from a particular perspective, the combination could be described as a political masterstroke, taking a key policy plank from camps on either side of the compact city argument, potentially silencing critics in both. 

The question remains: will this strategy address housing affordability issues within the city? 

While readers might prefer a forthright answer, a more candid assessment of the question is that it is too early to tell, and execution will play a critical role. But what is certain is that there are risks aplenty. 

Firstly, although tighter land use controls and higher land prices have been shown internationally to steer development up instead of out, it has done little to improve housing affordability as gauged by the median multiple (or the number of median salaries it would take to pay off the median house price, a useful international measure of affordability). 
  
Furthermore, just because developers build up, does not mean the residents of Auckland will buy into it. Much has been made of the quarter acre dream, which does not exist in the Auckland market in any meaningful way anymore, but it does reveal a preference towards houses with a garden. Ireland's building boom (and subsequent bust) serves as a very real reminder of what can go wrong when you restrict development to a very narrow profile, one that buyers don't necessarily want. 

Secondly, the release of green field land for development under the proposed RUB will take place along transit corridors that connect these areas to Auckland CBD. However, these areas are not a contiguous expansion of the city, but leapfrog the current urban footprint by tens of kilometres (a technical definition of sprawl, it should be noted). It also leaves significant portions of land adjacent to the urban boundary, currently allocated to agriculturally unproductive lifestyle blocks, completely untouched. 

If approved, the distance from a major satellite town like Pukekohe to the southern urban edge will almost be equal to the distance from the southern urban edge to the city centre. Even with the extension of rail services to places like Pukekohe, it seems a bit of a stretch to expect the increase in land supply in these areas to have much of an impact on the city's overall housing affordability given the distances involved. 

Lastly, if the assumptions around the deregulation and the land supply turn out to be spot on, there remains the question of how you get these developments over the line. The council may very well zone land in such a way as to intensify its use, but that doesn't necessarily mean the market will respond due to opposition from the NIMBYs (not in my back yard). 

Based on early public response to the first draft of the Unitary Plan, many Auckland residents appear to be in favour of intensification, just not in their neighbourhoods. Their concerns were relayed to their respective local boards, such that the proposed Unitary Plan was significantly watered down before officially being notified. 

This is on top of the council's own red tape, which had slowed planning approvals on big housing development projects to a three-and-a-half year crawl before central government intervened with the Housing Accords and Special Housing Areas Act. 

As stated earlier, there are risks aplenty. 

If the Auckland Council is committed to this path, then it needs some pointed strategies to address and mitigate the potential impact of these risks. Changes to urban form are expensive, and often irreversible. The problems we create today are the ones we have to live with tomorrow. 

Perhaps a better place to start is by demonstrating to the citizens of the city (and indeed New Zealand as a whole) that this approach is the best way forward versus all the other alternatives, a task that many opponents of the Unitary Plan feel has yet to be completed. 

Source: Auckland's Unitary Plan bold but risky