Coastal Processes, Hazards, and Society

The Sea Level Rise Adaptation


The Sea Level Rise Adaptation

Recall in Module 1 Lab 1A you responded to a prompt in a guided discussion using an interactive ArcGIS Story Map: US Coastal Property at Risk from Rising Seas. This tool allows the user to explore coastal communities and analyze the risks to properties in terms of flooding and financial loss. You can see the results for 2045 and 2100 shown spatially on the color-coded map. Some of the results are shocking. The year 2045 is 25 years away, so well within the lifetime of an adult who has a 30-year mortgage on a house in a flood risk zone. In many cases, jumping to 2100 gives a much more alarming view. One of the messages this tool provides is that sea level rise is happening now, not in an abstract way in the future, and that this generation must take action, and not leave it for future generations to address.

To this end, there are signs that more coastal communities in the U.S. are beginning to recognize the importance of sea level rise adaptation planning. On the other hand, a 2019 Climate Central analysis found that many cities are developing new homes faster in flood zones than in safer locations. New Jersey, Florida, and North Carolina stand out as the states building the most homes in flood risk zones. It is clear from these data that there is still a lot of work to do.

Climate Central has ranked U.S. cities based on their vulnerability to sea level rise: Go to Climate Central to view the three ranking lists. Note the three lists rank for, 1. Current flooding vulnerability (2017), 2. Flooding vulnerability in 2050, and 3. High social vulnerability populations at risk by 2050. All three of these lists rank New York city at #1 or #2, and the rest of the cities in the top 10 are in Florida. Note that the population exposed is critical to the ranking on these lists. Remember from Module 11 that the number of people exposed is a measure of vulnerability and social vulnerability (e.g., poverty, sickness, old age) increases the sensitivity of a community to sea level rise.

Please watch the PBS video below, Two cities, two very different responses to rising sea levels. It highlights and compares approaches to sea level rise planning in New York and Charleston, SC.

Video: Two cities, two very different responses to rising sea levels (9:19)

Click here for a transcript of the Two cities, two very different responses to rising sea levels Video.

JUDY WOODRUFF: Tonight, the NewsHour begins a series on the way communities prepare and survive disasters, both natural and manmade. NewsHour special correspondent Jackie Judd brings us a tale of two cities, both on the Atlantic Seaboard.

JACKIE JUDD: The crane towering over Rockaway Beach is a symbol of New York City's urgent, almost frantic effort to prevent a repeat of what happened in 2012 when Hurricane Sandy nearly brought the city to its knees.

DANIEL ZARRILLI, Mayor's Office and Recovery and Resiliency, New York City: We have 520 miles of shoreline. We have always been at risk of coastal inundation, but Sandy really changed the way we think about that risk and how we engage with the waterfront.

JACKIE JUDD: The response is not simply about minimizing hurricane damage. The larger issue, the issue making hurricanes more destructive, is sea level rise caused by climate change and a warming planet.

BENJAMIN STRAUSS, Climate Central: We're not labeling things with sea level rise when we should be.

JACKIE JUDD: Ben Strauss is a scientist with the research organization Climate Central.

BENJAMIN STRAUSS: A storm comes in, we have a damaging flood, and we say we had a storm, we had a flood. But every flood is deeper, bigger, and more damaging because of the sea level rise we've already had.

JACKIE JUDD: In the last century, the sea rose at least eight inches, and the rate has been accelerating since the 1990s. In the Rockaways, Mayor Bill de Blasio, recently and with great fanfare, opened the first stretch of a new concrete boardwalk built above the floodplain to replace the wooden one Sandy destroyed.

BILL DE BLASIO (D), Mayor of New York: This is also part of resiliency because all of these measures will protect, not just the boardwalk, protect the community beyond the boardwalk.

JACKIE JUDD: The boardwalk, so close to homes and businesses damaged by Sandy, is designed to hold back storm surge. It is only a piece of a $20 billion blueprint resulting from a collaboration with the state and federal governments and climate change scientists. Dan Zarrilli, who oversees the city's efforts, says first came an assessment of the city's risks and vulnerabilities, and from there, the more granular questions, dealing with hardening old infrastructure and building new infrastructure to withstand poundings in the coming decades.

DANIEL ZARRILLI: Even just considering the 2050 scenarios, about 8 percent of the city's shoreline could be flooded on a daily basis, just due to high tide, not even during a coastal storm event. And so thinking through the implications on neighborhoods, the investments we need the make to reduce risk and to handle that level of inundation is something that's driving our policies around our entire coastal protection plan.

JACKIE JUDD: New York City's aggressive efforts to prevent future catastrophe is not an approach that all cities facing rising sea level rise and other consequences of climate change are following. Take Charleston, South Carolina, which is known as low country for a reason. This spot just near the center of the city is only several feet above sea level. Sandy Bridges owns a small boutique nearby, in Charleston's vibrant Tourist District.

SANDY BRIDGES, Business Owner: High tide, rainy day, we just always experience flooding here.

JACKIE JUDD: Guaranteed?

SANDY BRIDGES: It comes right up to my doorstep on a really heavy downpour.

JACKIE JUDD: This is what it looked like near her store in 2012 after Hurricane Isaac brushed by the city. The fast-growing region is one of the Eastern Seaboard's most vulnerable. Waterways snake through the city and neighborhoods have been built on landfill. Flooding has plagued the city for generations, but it's getting worse.

CHRIS CARNEVALE, Southern Alliance for Clean Energy: At a particularly high tide, floodwater already comes in through the seawall and through the sidewalk and it fills the street right here at this intersection.

JACKIE JUDD: Environmentalist Chris Carnevale says sometimes it doesn't even take rain during an unusual high tide to trigger what the locals call nuisance flooding.

CHRIS CARNEVALE: We used to see about four-and-a-half days of nuisance flooding per year in the mid-20th century. Now we're up to about 23 days per year. When we project that into the future, as seas continue to rise, that's going to look — that's going to be many more days per year.

JACKIE JUDD: Even so, business owners, scientists, and environmentalists say, unlike New York, officials are moving too slowly in planning and seeking the necessary funds.

FRANK KNAPP, South Carolina Small Business Chamber of Commerce: They are taking some efforts, but those efforts are simply very inadequate.

JACKIE JUDD: Frank Knapp organized small business owners to agitate for swifter action. They have posted blue tape on door fronts to remind tourists of the flood line in a surge.

FRANK KNAPP: When the public actually takes the time to learn about the inundation threats under very small levels of sea level rise, one or two feet, I think they're going to be very shocked and they're going to be demanding that the city start doing some planning.

JACKIE JUDD: It's been more than a quarter-century since Charleston had its Sandy, Hurricane Hugo in 1989. So that sense of urgency is absent. And in a politically conservative state such as South Carolina, climate change is a difficult subject.

BRIAN HICKS, The Post and Courier: They put that report in a drawer. They didn't want it to see the light of day.

JACKIE JUDD: Political columnist Brian Hicks says, in 2011, scientists at the state Department of Natural Resources produced a report intended to sound the alarm, but political appointees shelved it.

BRIAN HICKS: When they did finally release it, they changed the executive summary, and there were all these things about, you know, that some scientists think this, and some scientists think that. It was very much a denial factor here, and they deep-sixed it.

JACKIE JUDD: Predictions for sea level rise in the next 100 years range from one foot to six feet. In Charleston, the creeping blue in this government map shows flooding that would occur at high tide with one to five feet of sea level rise. The higher-end would wreak havoc. Liz Fly is part of a team of state scientists overseeing coastal conservation.

ELIZABETH FLY, South Carolina Sea Grant Consortium: There is the risk and likelihood of some communities going underwater with increased sea level rise.

JOSEPH RILEY, Mayor of Charleston, South Carolina: Climate change is not going to remove Charleston from the landscape.

JACKIE JUDD: Joe Riley is the longtime mayor of Charleston.

JOSEPH RILEY: There's no cause for — to despair. It's all — the incremental improvements will protect this beautiful, historic city.

JACKIE JUDD: The most significant improvements to date, according to Mayor Riley, are fortifications to the battery at the point of the Charleston Peninsula, and this extensive new drainage system designed to pull water out of the city as fast as it comes in. But there is no broad adaptation plan in place. Are you planning on a one-foot rise? Is that the working assumption?

JOSEPH RILEY: We're planning on a range. It's incremental. We — and each year or decade, you will further calibrate that.

JACKIE JUDD: What is the range?

JOSEPH RILEY: Well, the range, you need to ask our resiliency people, but we're — we see some — some a foot, some less than a foot, some more than a foot.

JACKIE JUDD: Mayor Riley later clarified that he wasn't suggesting one foot was adequate for planning and described the drainage project as only a serious beginning to Charleston's preparations. Still, the administration has significant catching up to do.

ELIZABETH FLY: It's important for a community to look at that range of scenarios and think about their risk management, and think about what decisions are high-risk, and so maybe you should plan for a more extreme case of sea level rise, while some other decisions, it might be OK to plan for.

JACKIE JUDD: But that — that has not been decided in Charleston, right?


JACKIE JUDD: New York City's robust approach is more the exception than the rule along the East Coast, especially among smaller cities like Charleston.

BENJAMIN STRAUSS: This is a hard issue to really digest and tackle. We have no legal precedent, we have no institutional precedent for the idea that land will be disappearing. And we're ultimately going to need to take a very deep look at it to preserve the heritage of our city.

SANDY BRIDGES: One hundred years ago, they started planning and preserving and conserving Charleston. And 100 years from now, I want another little local business owner to be able to stand here and say the same thing. So, that's what honestly concerns me, is that 100 years from now, this could be lost.

JACKIE JUDD: Charleston Mayor Riley compares the threat of rising sea to an enemy invasion, which is just how New York City is behaving as it builds new defenses. For both cities, there is no doubt that the enemy is on the horizon. For the NewsHour, this is Jackie Judd in Charleston.

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