Just as Tropical Storm Cristobal prepared to make landfall in Louisiana, the Army Corps of Engineers (COE) released a plan on Saturday to spend nearly $5B to build miles of sea walls around parts of Miami that are vulnerable to storm surge and sea-level rise, local media there reported.  The plan reportedly calls for “moveable barriers” at the mouths of three waterways, elevating and floodproofing in large areas of the city, and restoring mangroves, but does not include moving residents to create more open space for floodwaters.  Sea-level rise could be as high as 13 feet in Miami.

Why This Matters:  Similar studies by the Army Corps are going on all over the country — New York City, Norfolk, Virginia, and in the Florida Keys.  The feds abruptly pulled in February the COE’s plans for a sea wall for New York City without comment. New tools are being developed that take into consideration more than just engineering and flood vulnerability per se, but that also look at issues of economic and social justice, such as poverty and inequality, outdated infrastructure, poor governance, and discrimination. There are likely cheaper and more effective approaches because anyone who has ever dealt with flooding knows that water always wins.

CORVI 

For example, a consortium of NGOs, philanthropy, and insurers led by the Stimson Center has just launched a tool called CORVI (Climate and Ocean Risk Vulnerability Index) that analyzes a city based on a ranking of risks that is designed to support smart future investment in climate resilience. It is a tool for decision-makers to identify and categorize risk across sectors and aid in the design of integrated policy solutions to build climate-resilient cities. If they don’t look at the range of social, economic, and environmental factors together, the solutions could make the overall problems worse with devastating consequences for the security of city residents, states, and the U.S.

COE

The Corps has spent $3M on the study in Miami, and it took 3 years to complete.  But Boston has been facing the exact same issues and rather than building mechanical barriers and high walls, they are looking at more natural approaches.  In fact, the Sustainable Solutions Lab at the University of Massachusetts analyzed the feasibility of installing a pair of barriers across Boston Harbor similar to what the COE proposes and found that it is expensive and would not actually function well.  They estimated that to construct a permanent storm barrier would be cost up to $20B and require intensive maintenance and it would impede the natural flow of water needed to maintain water quality.

To Go Deeper: The public is invited to learn more about the study and its findings at the identical virtual sessions, scheduled for 5-7 p.m. June 9 and 1-3 p.m. June 11. USACE staff will be available to answer questions.  You can register for them here.

What You Can Do: Provide comments to the COE on their Miami Dade Plan by clicking here.