When faced with floods, some international communities decided not to fight the water, but give it more space. As sea levels rise, could this also be an option in the US?
Water is the most powerful force on Earth. Although a single drop might not seem to make much of a difference, billions of them have carved the Grand Canyon out of the high plateaus in the American West. Each year, monsoon rains carry billions of tons of sediment down from the Himalayas to the ocean. Glacier ice has scoured away mountains to form deep and narrow valleys. And endlessly crashing waves erode away coastal cliffs. Yet when disaster strikes, promises are made to build back better even before the floodwaters have receded.
For centuries, people have been drawn to the rivers and coasts to settle. Globally, nearly 40% of the world’s population lives within 60 miles of the coast, and more than 600 million people live in low-lying coastal areas. In many places, people protect themselves from flooding by building sea walls, levees, or even storm surge barriers. However, there are also examples of communities across the globe where they followed a different track. They don’t fight the water, but set aside land to flood, which can bring a host of other benefits as well.
In the United Kingdom, they are recreating space for coastal salt marshes. Near Medmerry on the southern English coast, an area that used to be protected by a levee is currently connected to the sea. This creates an intertidal zone with mudflats. Premium cheeses are made from cows grazing in these salt marshes. The area also provides a home to wildlife and plants, and draws in tourists enjoying the quiet beauty. Furthermore, the area acts as a buffer zone: it can absorb flood waters and sharply reduce the cost of sea walls and levees necessary to protect nearby communities.
Sometimes more drastic measures are necessary. The ground underneath Jakarta, the capital of Indonesia, is sinking. As a result, the city is facing more and more flooding and will be completely below sea level in the future. It has come to a point where the president has decided that the best option is to build an entirely new capital city elsewhere. Low-lying island nations, where people do not have the option to moving uphill or further inland, are particularly vulnerable to sea level rise. The government of Kiribati decided in 2014 that sea level rise posed a significantly existential risk, and bought land in Fiji that its residents could potentially relocate to.
A similar strategy has been implemented along the rivers of the Netherlands. The goal of the Room for the River program was to restore floodplains to accommodate high water levels. These open spaces are used as protected areas, for recreation, or for uses such as seasonal livestock grazing when the water levels are low. When the water levels are high, these flood plains are inundated and store water in order to decrease water levels near critical infrastructure and densely populated cities. In a few locations, people were living in the floodplain before the program was implemented. The Dutch government has purchased the homes of these residents, in order to allow them to move to a safer location and restore the floodplain.
Would these solutions from across the globe also work in the US? Fortunately, there seems to be no immediate need to relocate entire cities – only in the worst-case scenario would sea levels rise so much over the next few decades that some communities might be invaded by the ocean. However, at smaller scale, making more space for the water is actually something that is already happening. There are government programs in place that purchase properties damaged by flooding in places deemed very high risk. The homeowners receive the (pre-damage) market value for their home, allowing them to buy another home in a safer location. These so-called buyout programs have already helped more than 43,000 households across the nation to move out of flood prone locations. These buyouts have taken place in places as varied as Houston, TX, Staten Island in New York City, and rural communities in the Midwest. In some counties, almost entire neighborhoods have been removed, but in many places fewer than 10 households have relocated.
Although it’s not cheap to purchase damaged homes, the Federal government has estimated that it saves $7 for every dollar invested in such flood prevention measures. The open space that is left after the home has been removed can be turned into a park, community garden, or natural habitat. Mangrove forests and coastal wetlands are particularly good at reducing flood-related damages. It has been estimated that wetlands prevented $625 million dollar in damages when Sandy hit the Northeast in 2012. Over a 20-year period, natural coastal buffers could reduce $50 billion worth of damages along the Gulf Coast.
Along rivers and near the coast are attractive locations to live. However, climate change will bring more flooding. For centuries, the Japanese have tried to warn their future countrymen about these dangers by placing tsunami marker stones that indicate where previous floods have destroyed homes, and which offer the advice to build uphill from where the stone is located. Next time a disaster strikes and people call to rebuild in the same place, ask yourself if that is a wise decision in the long run. This year’s World Oceans Day focusses on protecting Life & Livelihoods along the coast. Sometimes the best protection is giving the water a bit more space.
Carolien Kraan is a doctoral researcher at the Abess Center for Ecosystem Science and Policy at the University of Miami. Her dissertation research aims to support climate change adaptation that is sensitive to a wide range of societal goals, including equity and environmental justice. She is particularly interested in the idea of making more space for the water through strategic managed retreat. She has studied managed retreat in the United States by looking at where FEMA-funded voluntary property buyout programs have taken place, and has also written about policy options to address equity concerns that have been raised about buyouts. Prior to joining UM, Kraan worked at Stanford University, where she focused on integrative assessments, including on the relationship between climate and conflict. She has also worked as a researcher and policy advisor at the Energy research Centre of the Netherlands (ECN), and holds an MSc from the University of Edinburgh, UK, and a BSc from University College Roosevelt, the Netherlands.