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The Smith's Point neighborhood in Madaket after a particularly nasty storm in 2009.

2nd Annual Beach Erosion Forum Summary, part 1

Part 1 of a two-day event co-sponsored by the Nantucket Coastal Conservancy

At the beginning of May, the Nantucket Coastal Conservancy, UMass Boston Nantucket Field Station, UMass Boston School for the Environment, the Nantucket Civic League, the Maria Mitchell Association, the Nantucket Town Association, the Nantucket Land Council and the Madaket Residents Association put on a two-day erosion awareness and solution forum.

The Second Annual Nantucket Forum on Beach Erosion: Strategies for Adaptation in an Era of Rising Sea Levels held at the Westmoor Club on May 8 and May 9 brought together national, regional and local experts on coastal geology, erosion and planning to ehlp enlighten Nantucketers on sea level rise and how to deal with. The Nantucket Coastal Conservancy had me cover the event over the two days. I wrote summary pieces for each day. Below is my summary for May 8. I'll post my May 9 summary on Saturday afternoon

Enjoy!

Summary of the Second Annual Beach Erosion Forum - Friday, May 8, 2015
 
By Peter B. Brace
 
Adams Island, the Gravel Islands, Tombolo Point, Dry Shoal, Skiff Island and Little Gull Island were all once part of what is loosely known as the Muskeget Island group.
 
They existed between Bigelow Point on Tuckernuck Island’s western end and the southeast side of Muskeget Island.
 
According to Edward Wayman Coffin’s “Nantucket’s Forgotten Island: Muskeget,” the lower, southernmost Gravel Island had the Gravel Islands smallpox hospital on it, consisting of two buildings built by Nantucketer Dr. Samuel Gelston in 1770 to isolate seamen inoculated with smallpox from the rest of Nantucket.
 
Since then, all of these islands have succumbed to sea level rise heavily exacerbated by hurricanes and nor’easters over the last few centuries. Also inundated by the rising Atlantic Ocean was Billingsgate Island just west of Wellfleet, Mass., said Jim O’Connell of Coastal Advisory Services of Brant Rock, Mass., during his talk at the Second Annual Nantucket Forum on Beach Erosion: Strategies for Adaptation in an Era of Rising Sea Levels.
 
O’Connell told roughly 125 people in attendance on May 9 that Billingsgate Island, which finally disappeared in 1942, once had more than 30 houses on it and its own lighthouse. Sea level rise, coupled with ocean storms, eventually turned this little island into a shoal now exposed only at low tide.
 
His was one of many foreboding statements made by eight speakers during this two-day event, held at Nantucket’s Westmoor Club, designed by the Nantucket Coastal Conservancy to further the discussion, and hopefully generate some solutions, on the topic of erosion of Nantucket and sea level rise. Broken up into two, two-hour sessions on the evening of May 8 and the morning of May 9, the speakers opened each day’s discussion with their thoughts, followed by comments and questions from the public. Two different themes punctuated each day’s discussion, with the global situation presented on Friday, and regional impacts and potential solutions happening on Saturday morning.
 
Friday, May 8 
 
Strategies for Adaptation in An Era of Rising Sea Levels: The Big Picture 

 
Dr. E. Robert Thieler  
 
Thieler, research geologist of the U.S. Geological Survey at the Woods Hole Coastal and Marine Science Center, is the person you need to listen to about sea level.
 
“We need to be nimble and flexible and highly adaptable in dealing with sea level rise,” Thieler began.
 

He detailed how the Northeast is going to be experiencing more rapid and severe sea level rise than the rest of the U.S. and then explained that rising oceans don’t come up like water filling up a bathtub. Heating of the planet by global warming warms the oceans, causing thermal expansion of the salt water, said Thieler, adding that fresh water from melting glaciers increases the volume of the oceans.

 
Thieler, stating that fresh water is less dense and therefore lighter than salt water, said rapid introduction of it into salt water from the Greenland ice cap is likely going to have impact on sea level rise along the East Coast. Currently, the Gulf Stream, warm surface water flowing north and east from the southern tip of Florida to an area between Greenland and the U.K., cools and becomes heavier as it reaches the North Atlantic. Here, it sinks, flowing instead south and west well down below the surface, ultimately moving to the surface where it warms again and flows north. The Gulf Stream is part of the Thermohaline circulation that circulates warm and cold water around the planet setting global weather patterns.
 
Thieler told erosion forum attendees that if the Gulf Stream is interrupted by infusions of fresh water from melting glaciers, and the general warming of the planet by trapped greenhouse gases including excess carbon dioxide and methane, then the Gulf Stream slows down, which, among other weather impacts, could cause sea water to back up behind a traffic jam of warming water that isn’t cooling off and sinking where it should in the North Atlantic. This could increase sea level rise on the East Coast of the U.S. beyond current predictions.
 
Thieler cautioned that even absolute cessation of greenhouse gas emissions won’t halt sea level rise.
 
“If we stopped emitting greenhouses gases, sea level would continue to rise for several centuries and that’s because of the inertia of the system,” he said.
 
Thieler noted that the last 7,000 years, during which rising sea level slowed to nearly nothing 5,000 to 6,000 years ago and created our current islands’ landmass, have been great for humans because the warming temperatures allowed agriculture and fishing. However, within the next century, “we’re going to a place we’ve never been before.”
 
He cited the peninsula of Charleston, S.C., as an example, which biannually gets warnings for slight coastal flooding with seven-foot tides, but that those warnings will come 355 times a year with a 1.6-meter rise in sea level. Nantucket, Thieler said, is sinking around a millimeter a year while the ocean is rising 2.5mm per year.
 
A similar fate is probably on the menu for low-lying Nantucket at 112 feet above sea level, which is likely to experience groundwater changes, inundation, habitat loss, safety issues, steadily increasing coastal erosion and wetland loss, said Thieler, who added that this “complicated problem with multiple impacts” would also cause sea water to push into the island’s freshwater supply, driving it up and inland.
 
“There’s a landscape change element, but then there’s what happens to sea level rise due to a frequency of flooding,” he said. “There could be nine 100-year storms in 10 years and 10-year events could happen every other year; there’s a lot we know, but there’s whole lot that we don’t know.”
 
Dr. Robert Young  
 
With a smile on his face alternating with a playful smirk, Rob Young, director of the Program for the Study of Developed Shorelines at Duke and Western Carolina Universities, and co-author of “The Rising Sea” with Dr. Orrin Pilkey, took dead aim at the current national plan, or lack thereof, for dealing with sea level rise.
 
“The take-home message is that even with a flat line of erosion, we as coastal communities, have to realize that it’s still going to keep rising,” said Young. “The big issue nationally is, we really have no plan on how to deal with this.”

Panning President Obama’s lackluster Hurricane Sandy Task Force, Young’s message to this year’s erosion forum attendees was that adapting to sea level rise cannot be one coastal property at a time, but instead must be a community-wide effort to protect natural resources and real estate at the same time.
 
“You can’t manage the coastal economy one parcel at a time,” he said. “Part of the message is doing wise coastal management, [which] requires a broader view to preserve the economy.”
 
Young noted that after Hurricane Sandy, property owners were allowed to rebuild and or protect their beaches however they wanted. Largely, Nantucket’s and the rest of the coastal U.S.’s response to sea level rise is to build higher over the flood plain as mandated by the National Flood Insurance Program, which he said isn’t the worst approach, however, it’s currently our only reaction to sea level rise.
 
“The problem with just raising structures on the oceanfront is, you have to hold beaches in place,” he said. “This is our current national policy right now.”
 
Saying it’s difficult to find a beach that isn’t being engineered and is in its natural state, Young worries no one has any idea what the cumulative environmental impacts are.
 
“I’d like to come back here in five years and develop a case study for how you brought everybody together; you have great beaches of natural sand,” said Young of Nantucket’s shoreline.
 
 
Cornelia Dean 
 
Dean, former science editor for The New York Times and author of “Against the Tide: The Battle for America’s Beaches,” and who is on the same page as Young, said she believes there’ll be six feet of sea level rise by 2100, three feet at the lowest.
 
Given her prediction, Dean agreed with Young that the National Flood Insurance Program isn’t helping coastal communities prepare for sea level rise because heavily developed beaches don’t recover as quickly from storm events as undeveloped beaches because erosion control structures interrupt and, in many cases, cut off the natural erosion and littoral drift of sediments up and down beaches.
 
“There is a constituency of ignorance at the coast,” said Dean. “People don’t want to admit the ocean is coming up and that they shouldn’t be building on the coast.”
 
She added that when the National Flood Insurance Program was enacted in 1968, the federal government hoped the high premiums would deter most coastal development, noting that there’s a contingent of people who’ve come to regard beaches as infrastructure that can be repaired like any other infrastructure. For example, said Dean, Logan International Airport is grappling with how to keep the airport open as the ocean rises, but it won’t survive unless our politicians work together on a solution. But this is a challenge in the current political world of sea level rise because of some politicians whom Dean called “NIMTOs,” not in my term of office.
 
“How are we going to get ourselves out of this situation?” Dean wondered aloud. “It’s a terrible situation and it’s only going to get worse. The only thing I can suggest is you can step well back and find out what are the values you have and grow from there, and see if you can develop a plan of action.”
 
 
Speaker discussion 

You can probably guess a lot of the questions Dean, Thieler and Young fielded after they spoke at the forum, but none of the 125 or so attendees expected such focused queries from several Nantucket High School students.

Are individual property owners taking measures to prevent erosion on their property?  Are property owners allowed to take measures to prevent erosion on public land near their property?
What is the predicted time frame in which Nantucket will be uninhabitable?
Where does the sand go?!
What effect can geotubes really have on such a limited span of beach?
Are Nantucket’s beaches being eroded faster than beaches in other parts of the world?
What is the volume of sand that has eroded? Is there a calculated rate for sand disappearance?
Are public funds being used to protect private property?  If so, how is this being justified?

 
Mostly silent during both days of the forum, Siasconset Beach Preservation Fund (SBPF) president Josh Posner questioned the notion of retreat over fortifying the coastline.
 
“Mother Nature is a powerful force and there are a [lot of] stupid things that have been done, but I think the question we have to ask is what are we going to do about it?” he said. “We think we’ve got an environmentally sensible approach that responds to most of those questions and issues.
 
“What are the things that can be done? Let’s work together. It’s a small island and we need to get rid of the divisiveness.”
 
A man who didn’t identify himself had this to add:
 
“When trees fell down on my house this winter, I felt I had the right to cut them up and take them away and then cut a few more down,” he said. “If I was down there (Baxter Road), I would probably do the same thing. I’d want to protect my property.”
 
Cormac Collier, executive director of the Nantucket Land Council, said that he’s seen Folger’s Marsh and the beach in front of it retreat 20 feet in the last two years and asked how Nantucket could adapt to loss of its salt marshes.
 
“A lot of attention has been focused on humans and sea level rise, and I fear that not enough attention has been focused on our environment,” Collier said. “There are amazing salt marshes in our harbors, but there’s no ability for the salt marshes to migrate.”
 
Young responded that being pretty adaptable, salt marshes on Nantucket should be surveyed for marsh migration opportunities.
 
The message for Nantucket from the speakers during this discussion portion of the evening was one of self-reliance. Each in his or her own words advised on how island citizens should proceed.
 
In telling the audience that Falmouth, Mass., wrote its own sea level adaptation plan, Thieler hinted that it was more or less up to the smaller coastal communities to prepare for sea level rise, saying he expects there to be federal funding for cities such as Boston and New York, but not much comparatively for the smaller coastal towns.
 
“It will fall back on good old-fashioned Yankee ingenuity,” he said. “Falmouth came up with a plan to adapt to sea level rise. I think if Falmouth can do it, Nantucket can do it.”
 
To get these coastal communities going, Young said there are no incentives for municipalities to make the smart, right decisions.
 
“We have to put the risk of coastal development into that economy,” Young said. “They have to decide where that vulnerability is, then the science will be valid, it will matter and I think that’s where our big failing is.”
 
Citing Taylor Swift’s $17-million house in Watch Hill, R.I., specifically Swift’s concrete wall- and boulder-strewn coastal bank in front of which remains no sand on what is a public beach, Dean said science problems aren’t the real issue here, but rather social problems of getting citizens of coastal communities to coalesce around a problem and generate solutions.
 
“Taylor Swift is occupying the public beach; that part of the conversation is not taking place,” said Dean.
 
Although Dean didn’t connect the dots at the forum, SBPF is doing the same thing: they’re occupying a public beach for their own personal, private needs.
 
“Not only has she deprived the public of their beach, [but] you are removing sand from the transport of sand to private neighbors next door,” said Young, adding that the problem can’t be fixed one property at a time by what he calls “coastal management by litigation.”

Thieler advised that approaches such as beach nourishment and geotubes should be viewed as experiments, not solutions, with the understanding that experiments can fail and that they are measures taken while another longer-term plan is in place.