NEWS

Could changing climate change Assateague for better?

Jeremy Cox
jcox6@dmg.gannett.com
A view of Assateague Island’s beach at Tom’s Cove after Hurricane Sandy passed through the area. The inlet was short-lived, filling back in with sand, but it provides a preview of what future storms could bring.
  • The formation of new inlets in Assateague Island is a question of when, not if, scientists say.
  • The inlet or inlets could be an environmental boon, helping bays flush better.
  • A new inlet is just a storm away.

For Assateague Island, climate change may have a silver lining.

Sure, scientists have documented that rising seas are dissolving the saltwater marshes along its west coast at an alarming rate. And global warming is fueling more-potent and more-frequent hurricanes, upping the island's risk for batterings by the forces of Mother Nature.

But the news isn't all bad: A growing consensus of scientific evidence suggests that the powerful storms and higher tides could provide a breakthrough for water-quality woes in the bays created by the island.

It would be a "breakthrough" in the literal sense.

In the future, Assateague won't be a single, unbroken swatch of sand covering 37 miles of Maryland and Virginia shoreline. It will be, at times, divided into two islands, maybe three. Maybe more.

However many cuts the island endures, the result will be a new inlet or inlets. Those watery shortcuts between the Atlantic Ocean and the coastal bays will finally free the water virtually trapped behind the lengthy island, triggering a potential cascade of environmental benefits, said Bill Dennison, a professor with the University of Maryland Center for Environmental Science.

In a place where nature still reigns, the only certainty is that it will happen.

"The next big hurricane, it's not if, it's when," Dennison said. "And there are going to be significant consequences — and probably for the better — when it comes to the flushing of coastal bays."

It will be a case of history repeating itself — with a modern twist.

A story of change

"Assateague" is an American Indian word that translates as "a place across," presumably meaning across the water from the mainland where the ancient people primarily dwelled.

A major theme of the island's history is change. Strong storms frequently shape and reshape the malleable land. Like any barrier island, the sand slowly marches toward the mainland over time as storm waters surge over the island again and again.

Sometimes, those storms are strong enough to rake out gaps in the sand that quickly fill with the surrounding water — a new inlet.

The progression of Assateague Island’s ever-evolving shore and inlets. No major inlets have formed since the Ocean City Inlet in 1933 due, in large part, to human impacts, scientists say.

According to the book "Shifting Sands," many inlets have formed in Assateague since record keeping began in the 17th century. Their names are lost to history and natural forces: Mattapany Inlet, Sandy Point Inlet, Sinepuxent Inlet, Slough Inlet, Green Run Inlet and Assateague Inlet, to name a few.

Nor'easters and hurricanes have created at least 11 inlets since the mid-19th century. But only a handful survived more than a few years before filling in once again with sand. And just one remains to this day — with a little human help.

The Ocean City Inlet, dramatically forged during an August 1933 hurricane, owes its longevity to jetties constructed immediately afterward to shield it from wave energy and getting clogged with sediment.

The reasons for the island's "relative stability" over the past eight decades "are not entirely clear," according to the authors of "Shifting Sands," a group that included Dennison.

Bill Hulslander is chief of resources management for the Assateague Island National Seashore, the caretaker of much of the island. He attributes the stability to an infrequency of storms during the period.

"We've just had this period of relative calm with storminess in the mid-Atlantic," he said.

Another theory is that a dune constructed down much of Assateague's length during a failed 1960s construction project has protected the island from overwash. The grasses and scrub that sprouted on the dune's leeward side helped keep its sandy surface intact.

Today, the only water routes from the coastal bays to the Atlantic are at the Ocean City Inlet in Maryland and the Chincoteague Inlet in Virginia. Just don't expect recent history to dictate that it will stay that way forever, Hulslander said.

"There has been this history of inlets occurring along Assateague, and I think we expect to see that play out again in the future," he said.

The southern herd of Chincoteague ponies make their annual swim back to Assateague Island on Aug. 1, 2014.

Nature cleans up

The health of the coastal bays is no trifling matter. On the Maryland side alone, recreational activity accounted for $206 million in economic activity in 2000 while commercial and recreational fishing operations pumped in more than $30 million, according to the Maryland Coastal Bays Program.

On the whole, the health of the bays is improving north of the Ocean City Inlet, Dennison said. Restoration efforts, such as the removal of the Bishopville Dam, appear to be paying off.

But Chincoteague Bay, which comprises most of the lower half of the bay system, is ailing. Having more than 3,000 people on septic systems on Chincoteague Island doesn't help, Dennison said. While the systems remove bacteria, they do little to filter out nutrients that serve as fertilizer for algae blooms in the bays.

The bays face a similar threat from the north. Ocean City pumps its treated sewage into the ocean, but the north-to-south currents carry the plume into the back bays through the Ocean City Inlet, Dennison said.

A new inlet would go a long way toward easing the ills of the bays, Dennison said.

It would help flush out decades of nutrient buildup in the sediment. It takes up to 63 days for water in the middle of Chincoteague Bay to cycle out of the bay system, researchers say.

"Stagnant may not be the right word, but additional flushing would help," said Dave Wilson, executive director of the Coastal Bays Program, a nonprofit partnership among local, state and federal agencies.

Another benefit: The cooler ocean waters would stave off overheating during summer months, which led to vast die-offs of habitat-supporting aquatic grasses in 2005 and 2010, Dennison said. Fishermen would just have to get used to catching fish in the bay they normally would find in saltier water.

Mid-island view looking South of Chinoteague Island toward the inlet and the Atlantic Ocean.

Location uncertain

A lot depends on where the new inlet or inlets form.

If the sea punches through the land too close to an existing inlet, it won't do much good for flushing the bays, Dennison said. Such was the case of an overwash in the wake of Hurricane Sandy in 2012 that appeared only a few hundred yards north of Chincoteague Inlet. It didn't last long either, closing after a few weeks.

The most-promising candidates are those locations that were already inlets once, Hulslander said. Such swaths are distinguishable by their lack of woody vegetation. They also are visible in aerial photographs as bulges of land on the west side of the island — the remnants of an old inlet's delta.

A new inlet could pose issues, of course, for the island's 2 million annual visitors, Hulslander said. Again, location matters.

For the first time in the park's history, managers are considering what they would do in the event of the formation of a new inlet. In drafts of the new general management plan, the National Park Service contemplates using ferries, for instance, to shuttle visitors to the island's sights if an inlet occurs in the developed areas, Hulslander said.

But the island's most famous residents, its pony-size horses, probably won't require such accommodations. Hulslander said they have lived on the island for centuries and weathered whatever nature has thrown at them, including new water barriers.

Dennison cautions that humans shouldn't wait for nature to take care of their problems. Fixes, such as retrofitting Chincoteague Island with sewers, are still needed to protect the health of the bays.

"It might be a long wait and it may not have the consequences you want," he said. "We still have to clean up our own act."

jcox6@dmg.gannett.com

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