Wednesday, June 19, 2013

Coastal Flood Risk Reduction:  Planning in the face of change

Written June 18, 2013, published June 19, 2013

The National Disaster Preparedness Training Center, NDPTC, funded by the Federal Emergency Management Agency (FEMA) presented a one-day course on planning for coastal flood risk reduction at the WSU-Long Beach Research Station, June 4, 2013. Attended by a class of one dozen professionals and local citizens, the focus was on recognizing coastal flooding risks, benefits of several different types of coastal natural environments, traditional and non-traditional solutions, and the capabilities needed to increase resiliency in coastal communities. The pace was fast, the handouts copious, and the outcome positive.  For those who attended, coastal landscapes will never be seen in the same way. 

Half the population of the United States, 153 million people, is concentrated in its coastal counties. Coastal shorelines have urbanizing landscapes as populations increase. Yet coastlines are by their nature dynamic. We tend to try to ‘fix’ shorelines in a particular shape or position to suit our needs. But dynamic shorelines are going to find their own shape and placement over time, and fighting this process is getting more expensive with each passing decade.  

Flood damages (as measured in billions of dollars each year) are trending sharply upward. As a result, FEMA and NDPTC have changed their approaches to flood management from a focus on structural protection to a broader focus on damage avoidance and community resilience.  Resilience includes a diverse group of strategies, and assumes that as conditions change, solutions will readjust to reflect changing situations. 

The group delved into numerous definitions of risk, but came back repeatedly to the understanding that severe natural disasters can provide opportunities to rebuild communities, revitalize commercial districts and improve natural resilience.  After a quick review of relevant federal laws, which in some cases have precedents that date back many hundreds of years, and a discussion of “no adverse impact,” the class envisioned fully resilient coastal communities, and then moved to a detailed review of processes that impact coastal flooding. 

These processes include land-driven factors, such as rainfall and erosion, and for a local example, rain-on-snow events, which frequently result in flooding in riverside communities. Ocean factors include storms, storm surges, and tectonics. We then moved on to natural and beneficial structures, including marshes and mangroves. On low energy coastlines, barrier islands and mangroves provide very important natural energy buffers from storm surges.  On high energy shorelines, like ours, healthy outer dunes with ample sand supplies on the beach and in nearshore waters are important to maintaining natural energy buffers.  

Resilience was the key idea to which the class kept coming back. A community that adapts to change after damaging events is a community that promotes resilience. Doing things the same old way, again and again, is not adaptive in the face of change. The class formed three teams to work through a Cascadia subduction event, an earthquake/tsunami, representative of a realistic disaster scenario for this beach with resilience in mind. Out of it came three different ideas: 1. to build evacuation structures, 2.  to strengthen outer dunes, and 3. to promote a tax-base local funding solution for desired structures, whatever these might be.  

We looked at retreat plans, accommodation plans, expansion of natural and artificial coastal buffers and ways to reduce risks to coastal communities using all these tools. Land use regulations and building codes came up, along with a discussion about how proactive planning can help communities recover after a natural disaster, or completely miss out on opportunities though lack of response to changing conditions. A review of revenues and expenditures, as with other sections, took the class through several different countries. 

The class ended with a discussion of overarching ‘mega strategies’ developed by low-lying countries, such as the Netherlands and Maldives, and by coastal Alaskan communities. Along the Bering Sea, native Alaskan communities are losing their lands as permafrost melts, and are retreating to new higher locations that wrenchingly, mean a complete change of lifestyle for the residents. 

As an ecologist, this is the first time I’ve taken a class on emergency preparedness that so thoroughly incorporated long term planning into community disaster plans. The presentation is well worth a day’s time for local residents, planners, emergency preparedness staff, and community officials at all levels.  It is thoughtful, thought-provoking and represents a practical way to think about landscapes so that coastal communities have a future in the face of rising sea levels, increasingly severe storms and major tectonic events, such as Cascadia subduction zone earthquakes and tsunamis.

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