Hurricane Katrina's devastation helped change the way building professionals think about community planning.
Hurricane Katrina's devastation helped change the way building professionals think about community planning.

In the 10 years since Hurricane Katrina devastated the Gulf Coast, communities around the world have re-evaluated urban design and development, in terms of being better prepared for severe weather and rising sea levels and building for resilience.

Research from the Urban Land Institute has found that the strategies cities are implementing to improve resilience are helping in another way, too, by improving local economic prosperity and the quality of life. Here, BUILDER talks with Sarene Marshall, executive director for ULI’s Center for Sustainability, about how the community resilience movement is reshaping urban areas. 

This historic building in New Orleans, reclaimed since Hurricane Katrina, includes ground floor retail and offices. It is one example of the way that communities are rebuilding stronger since the storm.
This historic building in New Orleans, reclaimed since Hurricane Katrina, includes ground floor retail and offices. It is one example of the way that communities are rebuilding stronger since the storm.

How did Hurricane Katrina affect communities around the world?
The scale of destruction and loss of life associated with Hurricane Katrina was a real wake-up call regarding the increasing risks of climate change and extreme weather, and the importance of building smartly in the face of these challenges.

In the post-Katrina years, New Orleans has remade itself into a city that is no less unique and entertaining than it was before the storm, but one that is far more resilient, because it has focused not just on building back, but building better.

As part of the rebuilding process, New Orleans has acted strategically on several fronts, including restoring marshland and wetlands to help absorb floodwaters; incentivizing the construction of appealing, affordable housing using green technology; and diversifying its economy to reduce its dependence on oil and gas. The result is a city that is more environmentally sustainable, socially cohesive, and economically prosperous, and is as a result attracting new residents, businesses and investors.

What’s happened in New Orleans is happening in places around the world, as building for resilience and adapting to climate change have become top priorities.  Urban development -- from densely populated coastal cities to oceanfront resorts -- has been and will be increasingly affected by the impacts of climate change, including rising sea levels, extreme heat, drought, and storms of greater intensity.

As the resilience movement has gained momentum, we are seeing innovative approaches to the planning, design, development, financing, and insuring of real estate. And, as these strategies have evolved, we are seeing greater acceptance of the reality that it is not always possible -- or wise -- to keep building homes and businesses exactly where and how they have always been built. This is compelling the real estate industry to work ever more closely with the public sector and other community stakeholders to develop in a way that better protects both the built and natural environment by conserving energy as well as land and other resources.

You mention that resilient design strategies improve economic prosperity and quality of life. How does that happen?
What we’re finding is that many of the same practices that make communities more resilient to extreme weather and rising sea levels also make them healthier and more attractive places to live, which strengthens their triple bottom line of social, environmental and economic performance. To improve overall resiliency, more and more communities are taking a holistic approach that involves a combination of these strategies:

·         Developing compact, walkable, mixed-use communities – Community design influences how residents relate to each other. Communities that are highly walkable and which encourage a high degree of social interaction are more resilient to disasters, because the residents are more apt to know each other and help one another. These types of communities also foster greater inclusivity and social equity.  

·         Investing in social capital – The public and private sectors are working together to establish greater social infrastructure with community amenities (e.g., parks and trails) that provide opportunities for people to meet each other, including programming, fitness activities, and greater connectivity to other parts of the community. These same facilities can also buffer stormwater or provide emergency escape routes.

·         Building resource-efficient and durable housing – Communities are encouraging the development of resource-efficient and durable housing that is not only better able withstand extreme weather, but which reduces energy and water use, resulting in lower utility costs.

·         Continuously adapting for a changing context, be that environmental or economic – Being resilient means focusing on adaptation and flexibility of space, so that building uses can change over time to 1) meet the new needs and preferences of residents, and 2) be better equipped to withstand environmental and economic stresses.   

How can the design of a community better prepare it for severe weather?
Appropriate strategies to increase resilience in communities vary based on the context, the types of risks faced, and the scale of action.  For an individual building in a flood zone, these might include elevating mechanical equipment above the first floor and designing lower levels with water-tolerant uses and surfaces. ULI has several publications to help guide practitioners in the appropriate strategies to consider.  Essential, of course, is understanding risks, so that strategies can be tailored to regional- and site-specific contexts. ULI’s A Guide for Assessing Climate Change Risk provides a framework for prioritizing actions based on the frequency and severity of potential climate events, and the anticipated damages associated with such occurrences.

ULI’s Resilience Strategies for Communities at Risk provides guidance for how cities around the globe can improve their resilience to environmentally-related stresses. Regarding land use, the report recommends identifying local land use typologies that address vulnerabilities within the built environment. In responding to the costs of preserving and protecting high-risk locations, communities should develop new land use overlay zones that balance the value of continuing existing uses with the cost of doing so. The report also recommends designing protective infrastructure to do more than protect. One way to accomplish this is to place an emphasis on soft infrastructure (natural and landscaped systems), which can act as flood barriers while also serving as community open space that improve livability.

Beyond these general recommendations, ULI provides a series of more specific examples for how communities of different types can address their resilience.  An important consideration in both of these publications is the relationship between built and human systems.  When it comes to resilience, strong communications, leadership, decision-making, and social cohesion are all important adjuncts to a well-designed building or city.