The earthquake on 22 February had a devastating effect on Christchurch City’s CBD, historic buildings and entertainment district with over 300 buildings facing demolition. In the suburbs thousands of homes are beyond repair while liquefaction, ground movement and lateral spread have also severely damaged transportation infrastructure, and the three urban waters (water supply, wastewater and stormwater) infrastructure.
The initial focus following a disaster is on rescue and relief, with the Government already planning to build up to 10,000 temporary homes. But the big picture questions are as yet unanswered. Where will it be sufficiently safe to rebuild? Are the approaches to managing growth adopted through the Greater Christchurch Development Strategy still relevant? Is centralisation of infrastructure such as wastewater the best model? What steps are needed to deliver a sound planning framework and resilient rebuild processes?
MWH’s National Planning Specialist Paula Hunter, Principal Planner Andrew Guerin and National Three Urban Waters Specialist Jim Bradley share their thoughts on how best practice planning will help to rebuild a resilient Christchurch, meeting the future environmental, social and economic needs of the community.
The top priorities of a community following a disaster are temporary accommodation for those in need, restoring basic services, and rebuilding civic infrastructure to help stimulate economic recovery and restore livelihoods. The need to rebuild quickly to sustain the wellbeing of the community must be balanced against the need to proceed prudently, improving the City’s urban design, resilience in infrastructure, meeting the community’s needs and avoiding or mitigating natural hazards.
Out of the devastating situation there comes an opportunity to rebuild a resilient city, shaping a ‘new’ Christchurch where people have the confidence to rebuild and in which they will enjoy living, working and playing.
A fundamental change to contemporary planning thinking on centralisation, infrastructure and land use activities is required. Taking a more comprehensive and rigorous view of geophysical risks facing Christchurch is critical. The earthquake has well shown the risks of liquefaction in lower lying areas. Climate change is expected to exacerbate flooding from the more intense storm events expected in future. Sea inundation is also a risk with predicted rises in sea level. It is up to us as professionals to allow for these natural events when identifying areas appropriate for redevelopment.
A liveable and workable city is one that achieves a balance of social, cultural, environmental and economic outcomes on a human scale. Having a CBD or a ‘heart’ is a critical priority for such a city, not only to attract tourists and visitors but to encourage people to live there. Otherwise there is a danger of a CBD becoming a sterile and unattractive environment. Even prior to the earthquake, the centre of Christchurch was not working well. It was too big, too spread out and too empty. With high rises being demolished, there will be opportunities to enhance the resulting open spaces, helping to make the centre an attractive place to live. As an offset to the new open spaces, sustainably designed low rise apartments and apartments providing higher density housing are an option. Investing in restoring iconic historic buildings to retain links to people’s sense of place and improving links to natural features such as the Avon River and Hagley Park will help restore the character that is so evocative of Christchurch. Developing small shops and cafes to complement the City’s identity and connecting places with walkways and cycleways will help bring the centre alive.
Retaining centralised retailing and entertainment areas is essential for the recovery of the City’s economy. But is it necessary to centralise other infrastructure such as the public hospital? The risk of having centralised infrastructure is high, as seen with the widespread damage to Christchurch's wastewater system that will take months to repair. A more dispersed model with true mixed-use environments in neighbourhood centres may be a better option for both infrastructure and housing.
Since the earthquake, suburbs in Christchurch have become more like villages with neighbours getting to know each other. The suburbs are alive once more during the day with more people working from home. The time of peak oil is fast approaching, another motivation for us to live closer to work. So now is the time to plan for more neighbourhood centres with local shops and cafes where people can build strong social networks in a village atmosphere.
A major need now is for strong leadership to bring the community, local government, agencies, landowners and businesses together to produce a uniting vision for the City. We as planners need to deliver a holistic planning framework and process that reflects the community's needs and wishes. The overriding factor is the urgency to act now while the effects of the earthquake are to the forefront - the window of opportunity for accomplishing post-disaster improvements is proven to be short as business owners, workers and residents leave to live and work elsewhere.
For us as planners and engineers, the Christchurch earthquakes have fundamentally challenged conventional approaches to city planning i.e. compact cities with urban growth limits, intensification around centres particularly the CBD, centralisation of infrastructure. The questions have to be asked whether this conventional planning approach which is in effect promoted by the current Development Strategy is the right framework under which the Christchurch of tomorrow should be developed.
Particularly given that the interim advice from the Structural Engineering Society of New Zealand is that “With the earthquakes that have occurred, there is a significant risk that the Canterbury area will be subject to a period of increased seismicity. This should be considered as a possible series of triggered events, rather than simply an aftershock sequence. There may be a period of up to 50 years or more, during which the seismic hazard due to smaller events near Christchurch is significantly increased” and that – “A likely scenario from one of these faults is another earthquake in the Magnitude 6-6.5 range, possibly again close to the CBD. This has the potential for similar actions to the Lyttelton earthquake, that is, a short duration event, with high ground accelerations”.
With advice like this, those responsible for the rebuilding of Christchurch need to take great care in developing the future form of the City and determining the future location of activities and ensuring the planning and provisions of ‘engineered resilience’ in the infrastructure rebuild. Decisions need to be underpinned by reliable data and evidence and hard decisions should not be avoided through political expediency.
The passing of the Canterbury Earthquake Recovery Act 2011 bestows far reaching powers on the Canterbury Earthquake Recovery Authority (CERA). The purpose of the Act includes facilitating, co-ordinating, and directing the planning, rebuilding, and recovery of affected communities, including the repair and rebuilding of land, infrastructure, and other property and restoring the social, economic, cultural, and environmental wellbeing of greater Christchurch communities.
CERA has the responsibility of developing a Recovery Strategy which is to be an overarching, long-term strategy for the reconstruction, rebuilding, and recovery of greater Christchurch. For the Recovery Strategy to be effectively developed and successfully implemented it needs to be collaboratively and transparently developed. It should be underpinned by sound town planning based on simple planning principles such as multidisciplinary approaches, community engagement, evidence based and informed decision making and basic as it may sound, it should restrict the building or rebuilding on at risk land or marginal land. We need to make sure we learn from our past mistakes and that through good planning we avoid future ones, including ensuring we adapt to climate change.
To find out how MWH can help, contact:
Paula Hunter, National Planning Specialist, on 09 580 4546 or email@example.com
Andrew Guerin, Principal Planner, on 04 381 5750 or firstname.lastname@example.org
Jim Bradley, National Three Urban Waters Specialist, on 027 436 1195 or email@example.com