Winter Storms Reshape Chatham's Coast

By: Tim Wood

Topics: Monomoy National Wildlife Refuge , Erosion

South Beach, on the left, took a beating from storms over the past three months, leading to extensive erosion on the mainland, especially at the Morris Island headquarters of the Monomoy National Wildlife Refuge.  SPENCER KENNARD PHOTO

Erosion Threatens Refuge's Morris Island HQ

CHATHAM – It was a year ago Sunday that an early spring northeast storm punched a hole in South Beach, about a quarter mile south of Lighthouse Beach, creating a new inlet in the barrier beach that runs along the town's eastern shoreline.

After a series of winter storms, that barrier beach looks more like Swiss cheese than a solid line of dunes.

The April Fool's inlet, as it became known, and the subsequent washing away of South Beach and North Beach Island are part of the predicted Nauset barrier beach cycle begun by the 1987 break across from Lighthouse Beach. Four nor'easters between January and March hammered the outer beach from Orleans to the tip of Monomoy, with the stretch from Nauset Beach in Orleans to South Beach opposite Little Beach and Morris Island taking the worst of the wind and waves. From the April Fool's inlet south, little is left of the barrier spit.

“That's where the action is,” Dr. Graham Giese, scientist emeritus and director of the Center For Coastal Studies' Land and Sea Interaction Program, said of the area.

Extensive erosion of the bluffs at the Monomoy National Wildlife Refuge headquarters on Morris Island.

Extensive erosion of the bluffs at the Monomoy National Wildlife Refuge headquarters on Morris Island.

Having removed or significantly lowered the barrier beach between the ocean and the mainland, the Little Beach neighborhood south of Lighthouse Beach suffered extensive flooding during each of the storms, in all four instances making the intersection of Morris Island and Little Beach roads impassable, sometimes for days at a time. Storm waves also battered the bluffs on the eastern side of Morris Island, causing “unprecedented” erosion, according to Matthew Hillman, manager of the Monomoy National Wildlife Refuge, which is headquartered on the island.

A portion of the refuge property on the island is protected by a rock revetment, but much of it is not. Some of the high bluffs lost eight to 10 feet in the storms, Hillman said, and an overlook had to be closed because it was undermined. Refuge personnel can't even remove a bench and informational signs out of concern that the earth on which they sit will tumble down the steep bank.

“That really can go at any time,” Hillman said, adding that there are four- to five-inch fissures in the substrate several feet inland of the edge of the overlook.

He's also concerned about the future of the staircase to the beach, to the west of which is a rock revetment, but to the east of which are unprotected bluffs, where trees that once stood at the top of the bank are now scattered along the beach. During the worst of the storms, Hillman said the stairs were battered unmercifully by the waves, continuously lifted up and slammed down.

“We really expected to lose that entire staircase,” he said. Its future isn't at all certain, and its loss will have a big impact on public access. “When that goes, we have to get creative,” he said.

The flooding of the Morris Island-Little Beach Road intersection created an access problem of a different sort. Since Jan. 4, the refuge has been inaccessible for 14 days, and for most of that time there was also no power, Hillman said. With the loss of protection from South Beach, even during less severe storms, such as last week's, the intersection floods.

“It doesn't take a big storm anymore to do it,” Hillman said. He's made inquiries about possible federal highway funds to help flood-proof the roadway, or at least study the situation to find creative ways to maintain access, and is also working with the town to develop solutions.

Once conditions dry up enough, the town plans to install two or three catch basins linked by a pipe that will drain the low intersection and allow the water to be pumped out at one location, according to Natural Resources Director Dr. Robert Duncanson. “That will make it a lot more efficient,” he said, and not block the road during pumping. This is probably a temporary measure, he added.

“The first choice is to keep the flooding from occurring in the first place,” Duncanson said. That means figuring out how to keep flood waters from the ocean from spilling over the low dunes along the shore and flooding inland areas. Because the shorefront in the area is privately owned, the town is working with engineers hired by neighbors to develop ways to prevent future flooding, such as building up the dunes.

Raising the roadway is an option, Duncanson said, although he added that it was raised a number of years ago to prevent flooding from a wetland to the north. “What we have to be careful of is we don't want to cause flooding on private property” by raising the road level, he said.

Along with immediate problems like access to the refuge headquarters, beach and trails, the erosion is prompting refuge officials to look at the long-term viability of the Morris Island facility sooner than anticipated. Hillman said the refuge's comprehensive conservation plan calls for planning to move the facilities due to erosion to begin in 2021; that will obviously have to start a lot sooner. Although none of the buildings in the headquarters complex are immediately threatened by erosion, the loss of the protection from the ocean provided by South Beach means that structures closest to the edge, such as the rest rooms, the National Weather Service facility and parking areas – as well as trails and access to the beach – will be in danger sooner than anticipated.

According to the CCP, there's really no space on the present site to relocate the existing structures without compromising the safety of visitors and staff. It suggests several options for relocating facilities, including a visitor station near downtown, leaving just administrative functions on Morris Island, or acquisition of another site to move the entire refuge headquarters operation.

“There are a lot of options, but I can't think of one good one,” Hillman said.

Another possibility is extending the existing revetment to the east, wrapping around the bluff, but Hillman said he has “serious misgivings” about that due to both the cost and the impact on the environment.

While he hasn't been able to get out to Monomoy Island recently, Hillman said it's obvious there's a lot of sand swirling around in the waters just east of the refuge and Morris Island. Should conditions become calm enough for that sand to settle, it could provide a buffer against further erosion, at least in the short term.

What Giese calls “relic” sand from South Beach, as it breaks up and moves to the west due to overwash, as well as sand from the more northern portions of the barrier beach system, will continue to move south, following the general pattern of sediment transport along the coast. There will be times when that sediment is added to the beaches and times when it will wash away.

“There's just an awful lot of sand” in the system right now, Giese said. Storms, when they happen, will continue to have a big impact due to the dynamic nature of the system, but they're a little like watching a sculptor work in a studio, he said, not knowing what the final piece will look like.

Meanwhile, Hillman is anxious to get out to Monomoy, which he hasn't been able to do because of refuge's boats are not yet in the water and, of course, the stormy weather. He's concerned about storm damage to the historic Monomoy Point lighthouse and keepers house, which was extensively renovated last year. While it is well inland from the water, Monomoy no doubt received its share of the greater than hurricane-force winds that some of this winter's nor'easters brought.

“That light tower just gets pounded” under those conditions, Hillman said. He's also concerned about how access to the islands may have changed due to the shifting sands, particularly around the 2013 inlet, which was already clogged with sand before the series of storms.

And any day now, piping plovers and other shorebirds that nest on Monomoy will be returning, if they haven't arrived already. April 1 is generally the start of the birding season on the refuge, and seasonal personnel will soon begin to arrive to augment the refuge's three-person full-time staff.

“April is a busy month for us,” Hillman said.