Miami, Florida’s challenge to control mounting sea levels

Sea-level rise (SLR) is one of the most prominent challenges to society regarding climate change at this time. Millions of people are living in areas that are projected to be high risk for sea water flooding, especially during storm surges. Many cities in south Florida are already regularly experiencing water in the streets. This leaves many coastal communities confused and anxious for the future.

A 2017 article in the BBC accounted for this issue, stating that “major cities like Miami and Fort Lauderdale are the eight most populous metropolitan area in the US” and that Miami especially “has the most to lose in terms of financial assets of any coastal city in the world.” Real estate directly on the coast of Miami adds up to well in to the billions. This is a location facing major SLR with both a booming population and very expensive real estate. The city of Miami was ranked the second-most susceptible city of the major coastal cities in the United States in 2005, considering all probable floods and existing protection.

The United States Department of Commerce has a center for the National Ocean Service called the National Oceanic & Atmospheric Administration (NOAA) which closely analyzes national infrastructure in relation to observing and predicting water levels. According to the NOAA, the US Gulf Coast SLR rates are often very high due to the gradual sinking in of the land. Sea levels in this area rise about 2.03 to 3.05 cm per decade. In turn, Miami has become a hot spot for engineers across the globe studying coastal city sustainability and SLR. It is also threatening to drinking water supplies as coastal aquifers may have to be completely changed to better control sea water intrusion which could cost locals in tax increases.

A study done by Adrian Werner & Craig Simmons analyzed the impact of SLR on sea water intrusion on coastal aquifers and contended, “there is a clear and urgent need to explore inward sea water-fresh water interface migration in response to changing global mean sea level in unconfined coastal aquifers.” In other words, the fresh groundwater supply is currently exposed to a surge of sea water with rising levels and more intense storms. Something has got to give in order to keep the city of Miami and others safe, but the real trouble is, who is going to pay for all of this new infrastructure.

A case study was performed by the Department of Urban Studies & Planning at the University of Maryland about the cost or benefit of building levees in Miami to mitigate SLR and storm surges. Results show the city would “benefit in implementing levee projects along the Miami River in both a 10-year storm event with SLR and cumulative long-term damage scenarios.” This is just one aspect of the solution as levees provide short term protection from growing tides. Other potential actions include seawalls and beach stabilization. These action plans are less controversial for policy makers but more expensive in the long term. This issue is likely to become social as well when the government determines who will pay for and receive these adaptation strategies.

Resettlement of vulnerable populations may be strongly objected by stakeholders but come with long term benefits. Unaffordable residents may choose to relocate instead of pitching in on high protection costs. Regardless of exactly how this pans out, it is time for the city of Miami and the Gulf Coast to step up to the plate and implement policies to keep the people safe before this growing crisis truly becomes out of hand.