Retrofitting for Resilience

Louisiana Resiliency Assistance Program (LRAP) Meeting<break>image: Coastal Sustainability Studio
A Louisiana Resiliency Assistance Program (LRAP) meeting
image: LSU Coastal Sustainability Studio

Over the last two years, my colleagues and I at the Louisiana State University (LSU) Coastal Sustainability Studio have been developing a program that provides resources to planning staff in Louisiana communities to integrate resilience into planning efforts, whether they are working on zoning codes, comprehensive plans, or water management plans. The results of the program to-date have been based on the development of an online, decision-support tool and a webinar and workshop series that included presentations from national experts and partnerships with regional practitioners to address local challenges in Louisiana. While cultural, environmental, and economic context is critical in proposing sustainable mitigating actions in response to risk, there are clear lessons that are transferable to communities around the US. The following is one of many strategies for resilience we have identified.

Communities spend large amounts of money on infrastructure improvements, including road maintenance, building renovations, and drainage and sewer repairs. Precisely because these retrofitting efforts represent costly community investments, they should be conducted in ways that achieve multiple goals: increase livability and sustainability, reduce hazards and risks, and prepare for post-disaster recovery.

image: Coastal Sustainability Studio
image: LSU Coastal Sustainability Studio

Why We Need a New Approach

Increased vulnerability to natural hazards demands innovative planning and design solutions. Twentieth century methods of storm protection and building construction, for example, no longer protect homes and businesses from flooding. Great opportunities exist to strengthen our communities through innovative public investments. However, these measures can require significant upfront costs, inhibit short-term economic development, appear redundant, and generate conflict amongst stakeholders. Retrofitting for resilience is challenging, and can too often be ignored in favor of short-term investments that deliver limited value. To address the complex nature of these challenges, emerging planning, design, and construction techniques, such as water resource management, home elevations, and innovative zoning, are being used around the world to allow communities to bounce back faster, smarter, and stronger after an event.

image: Coastal Sustainability Studio
image: LSU Coastal Sustainability Studio

Recommended Strategy: Retrofit for Resilience

The application of “resilience” to planning can do much more than prepare our built environment for a difficult and unpredictable future. Resilience planning can, in fact, catalyze positive change across communities and improve quality of life. The book Bowling Alone: The Collapse and Revival of American Community by Robert D. Putnam describes two types of community capacity: bonding and bridging. Within the framework of resiliency, “bonding” refers to a community’s ability to effectively use its own internal resources. “Bridging” refers to a community’s ability to seek out the external resources it needs. Both bonding and bridging are crucial capacities, allowing communities to be vital, thriving places. Retrofitting can be the means by which both types of community strengths are demonstrated and enhanced.

Retrofitting can occur throughout a community, from a single family’s renovation to a region-wide flood protection system. Certain retrofitting techniques are more effective at smaller scales, while others are suited for broad application. Examples of how this strategy can be applied are discussed below. Additional measures can be taken to implement this strategy, depending on the priorities and resources of individual communities.

Action: Retrofit buildings and landscapes to accommodate flooding.

When retrofitting buildings and parks, address day-to-day community needs while building in assets that will help the community weather future disasters.

How it works:

  • Go beyond existing building codes and FEMA Base Flood Elevation requirements.
  • Renovate civic buildings, such as fire stations, to meet the community’s day-to-day needs as well as post-disaster needs.
  • Passive and active recreation parks should be designed to accommodate flooding by storing water in wet and dry ponds or in the engineered soils used in sports fields.
  • Adopt stringent building codes and design standards that require wind proofing measures, such as hurricane straps, hurricane shutters, truss bracing, removal of potential windborne missiles, and garage door bracing.
image: Coastal Sustainability Studio
image: LSU Coastal Sustainability Studio
  • Adopt building codes and design guidelines that require flood proofing measures, such as: temporary flood shields, temporary gates or panels, flood resistant materials below the Base Flood Elevation (BFE), waterproof sealants, flood vents, and the relocation or elevation of vulnerable building equipment.
  • Homeowners in areas vulnerable to strong storms should install generators and renewable energy back up-technology, such as solar and geothermal.

Action: Incorporate green infrastructure.

This type of retrofit seeks to augment existing water management systems through the use of green stormwater infrastructure in road design, drainage, and sewage retrofits. The use of green infrastructure in drainage systems reduces point source pollution as well as peak storm flows in heavy rain events while providing the opportunity for groundwater recharge.  These techniques are increasingly being incorporated into new designs, retrofits of existing systems, and the maintenance regimes of public works agencies.

How it works:

  • Bioswales replace or augment sub-surface, piped drainage systems. Benefits of bioswales include: the removal of pollutants from stormwater, a reduction in peak storm flows, and an enhanced aesthetic in the built environment.
  • Retention/detention ponds can play an important role in adding capacity to existing stormwater systems, and can be designed to mitigate runoff water quality impacts.
  • Tree planting can have significant positive impacts to the ecosystem services in a community, and reduce the amount of stormwater that enters a drainage system.
  • Riparian buffers can provide water quality, water management, and biodiversity benefits, as well as opportunities for open space.
image: Coastal Sustainability Studio
Green infrastructure
image: LSU Coastal Sustainability Studio

Action: Retrofit critical infrastructure to be more resilient.

The impacts of extreme weather events, relative sea level rise, shifting precipitation patterns, and temperature variability pose challenges to public infrastructure in the energy, water, building, storm protection, and transportation sectors. These systems require significant investments, not only in up-front costs, but in ongoing maintenance. Integrating resilience through existing maintenance programs can provide funding for retrofits.

image: Coastal Sustainability Studio
Hardening public infrastructure
image: LSU Coastal Sustainability Studio

How it works:

  • Cities are addressing the vulnerability of their drinking water systems through the following strategies: relocation to less vulnerable places where possible, installing water-tight doors around crucial equipment, switching to submersible pumps, and creating protective barriers such as sea walls, dunes or tidal gates around important assets.
  • In the wake of major natural disasters, some state utility commissions have adopted new regulatory frameworks that seek to “disaster-proof” critical communications and electric infrastructure against extreme climate and weather events.
  • Increasingly, gas stations are required to have a back-up energy source: including being wired with a transfer switch to an alternative power source during a power outage and tax credits that incentivize installing emergency standby generators.
  • Funding stormwater infrastructure upgrades to address aging and increased stress on the system due to climate change is an ongoing issue for communities. Some communities are assessing whether property owners should pay a flat rate to retrofit to meet expanding service needs, employ new technologies, and comply with evolving regulatory requirements.

Action: Combine public recreation opportunities and flood protection systems.

Consider adding additional functions to land and infrastructure otherwise used exclusively for flood protection. Communities around the world have used this strategy to strengthen flood protection systems, increase passive and active recreation sites, and provide communal spaces for gathering and celebration.

A multi-use levee image: Coastal Sustainability Studio
A multi-use levee
image: LSU Coastal Sustainability Studio

How it works:

  • Relocate flood protection structures to accommodate more room for water bodies to flood.
  • Use derelict industrial water fronts to engage natural systems and provide open space for communities to enjoy.
  • Use bayous and other water bodies to link underserved neighborhoods, schools, parks, and other civic use buildings to downtown community cores.
  • Concrete drainage channels can be retrofitted to create useable public space that supports a variety of community and landscape types, while maintaining flood protection.

Action: Revert land uses to open space in areas with an elevated flood risk.

When development encroaches into the floodplain, flood risks rise. Many communities are working to remove residential and commercial land uses from these low-lying areas.

image: Coastal Sustainability Studio
image: LSU Coastal Sustainability Studio

How it works:

  • Purchase and remove structures from floodplains to return areas of communities to their original function.
  • When development on vulnerable land is necessary, mitigate wetland loss in your own communities.
  • Retrofit abandoned industrial sites by redeveloping the site into a usable space for surrounding communities and visitors.
  • Rezone areas that have experienced significant subsidence and have become unsuitable for development to allow for natural system restoration.
  • In areas vulnerable to sea level rise and adjacent to tidal waters, incorporate rolling easements into zoning codes and subdivision regulations.
  • Use zoning to allow space for community gardens, including on public land.
image: Coastal Sustainability Studio
image: LSU Coastal Sustainability Studio

In the current political and economic environment, fiscal responsibility is essential. By retrofitting with resilience in mind, these projects–infrastructure, buildings, landscapes, and flood protection–strengthen communities and ensure safer, stronger, and smarter development.

by Patrick Michaels, ASLA, a Research Fellow at the LSU Coastal Sustainability Studio. He can be reached at

Supported by the staff and students of the LSU Coastal Sustainability Studio

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