Mitigating natural disasters through landscape design

Dr Kristina Hill is an expert on urban and ecological adaptation strategies for coastal flooding and climate change. An associate professor at the University of California, Berkeley, she has developed a combination of analytical mapping techniques, community-based urban design and an adaptation-pathways approach to propose and evaluate design alternatives.

In 2018 Hill co-led a team in the “Resilient by Design” competition in the San Francisco Bay area. She has worked with US cities from New York to New Orleans, and Berkeley to Seattle, US federal agencies, and the Rockefeller 100 Resilient Cities programme. On top of that she’s also found time to publish work in a wide range of journals and anthologies and edited the book Ecology and Design in 2002.

Dr Hill will be presenting at the 2019 NZILA Firth Conference in Christchurch in November - her visit here is sponsored by Isthmus.

LAA: How can landscape design mitigate natural disasters?

KH: The definition of a "natural disaster" is changing in fundamental ways. Entire cities and urban districts are being built in places where a new climate is going to create existential problems. Fires, land subsidence and floods were once considered natural disasters, but all of these are becoming more extreme as a result of human actions. New city and suburban areas block water infiltration, creating more extreme surface flooding. Excessive groundwater withdrawals destabilise the ground. New structures in fire-prone landscapes set up conflicts between human safety and ecosystem dynamics.

The illusion of control over natural processes has allowed global capital to support dangerous investments, and landscape designers are often complicit in this process when they enter the process of development after these ill-conceived plans have already been made.

That's not new - but the speed and size of city-building and the conversion of undeveloped ecosystems is unprecedented now. At the same time we've accelerated the transformation of entire regions, we've changed our climate. Now the question is, which is going to cause the most new disasters - building in the wrong places, or supercharging the climate to the point where we're living on a new planet? The word "natural" is confusing and ambiguous now, becoming more and more difficult to use. But we're going to have lots of new words for disasters.

The role of design is changing. In addition to designing new spaces, our existing cities and infrastructure landscapes need significant investments in re-design. The critical need to both mitigate and adapt to the climate crisis will push us to change our basic ways of getting around, and moving people and resources around the world. Streets need to work for electric bikes and scooters as an alternative to cars, and battles will be fought over whether corporate-backed fleets of automated vehicles can dominate public rights-of-way. Cities will need alternative water supply and wastewater systems as coastal flooding accelerates. Airports and airplane fuelling systems will change, along with the expansion of renewable energy sources in cities, as well as in distant energy farms. Food supply chains will be altered by changes in global shipping with new Arctic routes, as well as reduced water resources and expanded urbanisation. We can't know all the ways this will occur, and how the surprises will interact with each other. But we know it will happen, and that nothing will seem stable.

Landscape design can help avoid damage and loss of life, while supporting healthy ecosystems and inspiring people to adapt. Designers and landscape planners can start by avoiding building on the most vulnerable sites. We can provide alternative designs that are more resistant to damage, or allow people to recover more quickly. Floodable development, ie, districts that are designed to function while flooded, provide one key example. Shelter-in-place neighbourhoods are another, where supplies are cached to prepare for fires and earthquakes. We can learn and implement better practices for making temporary housing areas that perform at a high level culturally and ecologically, since the whole world is going to have to house refugees with domestic and international origins. Corridors need to be designed and planned to allow animals and plants to shift poleward and to higher elevations as the planet warms.

But most importantly, we can use design to reinforce and encourage the social and cultural qualities of courage, resourcefulness and compassion. The history of memorial design and park design provides many lessons for how design can affect people's hearts and minds. Designers need to grasp these skills and use them, in the service of our sense of what it means to be human in a time of unprecedented change.

LAA: Rebuilding after disaster presents opportunity .. what can Christchurch learn from other resilient cities around the world?

KH: First let me say that Christchurch has become an unusually good example for the rest of the world. It's a city that took substantive actions to reduce risks after an earthquake event, by removing so many homes from a zone that would otherwise suffer repeated heavy damage in the next event. That's a great example of adaptation - not just recovering after the last event, but actually "changing shape" to be prepared for a future event. That's a lesson many cities need to learn from Christchurch.

Achieving resilience as the climate and global economy continues to change will require repeated actions, implemented in phases. The weather events that demand resilience will increase in frequency and magnitude, challenging our infrastructure and our expectations. The underlying challenge is to adapt.

In terms of present-day lessons from around the world - Japanese bosai earthquake preparation culture is the leading example, distributing cached supplies at community schools and sports facilities, and practicing vertical evacuations for a tsunami or hurricane.

Australian suburban areas have demonstrated how to cope well with bush fires using shelter-in-place structures. The German city of Hamburg has demonstrated that a floodable urban district can work by raising roads and structures. Amsterdam has shown that a floating neighbourhood (IJburg) can be vibrant and beautiful at the same time it is prepared for sea level rise.

IJburg consists of man-made islands connected by bridges.

American cities haven't done much adaptation yet, but coastal US cities do offer models of achieving rapid evacuation on a family-by-family basis - second only to the system Cuban cities use in hurricanes, where people manage to get their neighbours out of harm's way along with their own family members.

I hope to see more cities put the pieces together and move from resilience goals alone, to taking on both adaptation *and* resilience. I also hope more cities will realise that they can't be "climate proof" if their international supply chains and business partners aren't also climate proof, and if they aren't ready to respond to refugee crises in a humane way. The challenges are immense, and will turn many of our expectations upside down over the next 50 years. Adaptation will require as much cultural creativity as it requires functional creativity, while staying true to values that include compassion for people (and animals) that face very different circumstances to our own.

IJburg was developed to help with Amsterdam’s housing shortage.

LAA: What's the key message you'll be delivering at the conference?

KH: My main argument is that design needs to shape both functional performance and cultural performance, using all the muscular capacity of physical landscape forms for the former and the subtle language of memorials and fine art to achieve the latter. The scale of the challenges we face in a rapidly changing world, particularly the surprises that will come with the climate crisis, are hard to overstate. In order to maintain our sense of who we are as people, we will have to grapple with the function and meaning of landscape forms - from seawalls to super dykes, and from ponds to forests. Why will we keep some and remove others? I think the fundamental question is, what does it mean to be human in this unprecedented time, and how can landscape design offer something significant as an answer to that question?