Bethany Beach ultimately still at the mercy of tide and storm
There’s no way around it: Bethany Beach floods. Land in the town ranges from just below sea level to as much as 10 feet above it, with much of the town coming in somewhere between sea level and just 3 feet above. The result is that, whether it’s from tidal flow from the Indian River Bay and its tributaries or from heavy rain, there’s not much the Town can do to eliminate recurring flooding, though it has certainly tried over the years.
On Saturday, June 18, the Bethany Beach Landowners Association (BBLA) held its annual meeting, and Town Manager Cliff Graviet spent a substantial portion of his time updating members on just exactly where the town stands regarding its flooding problems.
The update came as the Town decides what, if anything, it can do next to try to address the issue, in the wake of a joint study with the U.S. Army Corps of Engineers that essentially gave the Town the same answer it’s been getting for decades: Without a major investment of funds, the status quo is about the best they can expect.
“We could spend several million dollars and take care of minimal events,” Graviet said, “But we will be flooded anyway with larger events.”
He noted that more and more of those larger events have been occurring in recent years, too.
“We’ve had complaints in the last couple years that it was working less, and we were flooded more than has been the case,” he acknowledged.
Even for “nuisance flooding,” the frequency of days with flooding is increasing over time, he said.
“We’re at or below sea level, and we’re experiencing more tidal flooding. We can’t figure out a way to combat tidal flooding. We’re no closer to solving that than when we started.”
Tidal and rainwater flooding pose trouble
Setting the scene for the local recipe for flooding, Graviet noted that the Loop Canal that runs through part of the town is a tidal body of water, which sometimes pushes large amounts of water into the town, overflowing its banks and sending water into yards and streets.
The Assawoman Canal that feeds it and runs to the south is also tidal, and the large ditch between the town’s Bethany West community and neighboring Sea Colony is partly tidal, all offering potential for adding water to any flooding event.
The bulk of the town’s development has happened since 1954, with “build-out” having been achieved by the early 1990s, Graviet said. That means the Town is dealing with a situation created many decades ago, including the impact of the manmade Assawoman and Loop canals.
Without the two canals — built for transportation, in a federal project in the case of the former and by the local community in the latter — he said, there would be 75 to 80 percent less flooding in the town.
Historically, “Drainage was driven by the developer, with no overarching plan on how to move rainwater,” he noted. The result was a number of “mega-swales” and a “patchwork quilt where developers tied into whatever was available.”
East of Route 1, drainage is now running through underground piping on Pennsylvania and N. Atlantic Avenues — an improvement over the former open swale, but Graviet emphasized that the Pennsylvania Avenue pipe needs to be replaced.
West of Route 1, drainage uses open culverts, or swales, that Graviet described as a “hodgepodge system,” and one that he said was largely neglected by the Town between the late 1980s and 2001.
The Town didn’t clean or maintain the swales, he said, and the ordinance that mandates that neighboring property owners keep swales clear was not enforced. The result, he said, was a “self-created problem” with rainwater flooding.
In 2002, a study identified tributaries being used for drainage, and the Town went to work to reestablish the swales, hiring three full-time employees charged with nothing other than doing that work.
Then, in 2006, the Town put $6 million into a plan to move rainwater “from Point A to Point B,” mostly in Bethany West, Graviet noted, adding piping to the former open swales on Pennsylvania Avenue and on Evans.
It was at that point, he said, that the Town “took a step back and decided moving rainwater wasn’t worth $5 or $6 million” when it had other areas to deal with.
So, today, the bulk of the Town’s rainfall from east of Atlantic runs into the Loop Canal. From the south, it runs to the Route 1 ditch, which then carries it to the Loop Canal. And, from the southwest, including Bethany West and Lake Bethany, rainfall, again, runs into the Loop Canal.
Graviet estimated that, in all, about 80 to 85 percent of the town’s water drains to the Loop Canal.
As a tidal body, the Loop Canal doesn’t necessarily lend itself to having a positive impact on stormwater drainage. Often, when heavy rain is coming it, tidal flooding is also pushing water from the bay into the canal.
To give perspective on the predicament the town faces regarding tidal flooding, Graviet displayed a map from 1991 that shows areas of the town that are repeatedly flooded, ranging from occasional to frequent and then extreme flooding. The map shows that the vast bulk of the town falls into one of those three categories.
Demonstrating the success of the Town’s past efforts to address rainwater flooding, Graviet noted that the “gullywasher” that had hit the area two days prior, on June 16, had drained quickly. But, he said, the open drainage system relies on the Loop Canal and tidal levels, and once the water gets there, it often has nowhere to go.
“This is quite a battle to fight,” he said. “The water is difficult to move, and there’s nowhere to take it. It’s a battle to keep the swales open for events that are not related to tidal flooding.”
In any tidal event, Graviet said, the water begins to fill areas close to the Indian River Inlet quickly. When that tidal flow enters Whites Creek, it develops more force, and perhaps counterintuitively, he said, eventually hits the Loop Canal with a force so strong that it sometimes doesn’t enter the Loop Canal itself but instead flows into the Salt Pond — which he said has created a 9- to 10-foot ditch between the Loop Canal and the Salt Pond, just from the tidal flow.
Additionally, when it runs out of room in the creeks that shoot off the bay, the water pushes over Fred Hudson Road at the north of town and into the Salt Pond, too.
Impact of proposed solutions more negative than positive
In the past, the Town has looked at the idea of placing structures — such as an inflatable “bladder dam” — into the Loop Canal to prevent the tidal flooding coming from there.
“They are used around the world,” he said, with the structures being raised at low tide to block water coming in with the tide.
While that might sound like a solution, Graviet said it doesn’t address the tidal flow from Fred Hudson Road to the Salt Pond. Moreover, he said, a bladder dam in the canal would, according to studies, increase the height of water in the Assawoman Canal during a tidal event. At that point, he said, any State interest in such a project waned, essentially taking it off the table.
The recent joint Corps study aimed to look at the problem from a larger perspective, studying the potential impact of a gate at the north part of the system and a bladder dam at Whites Creek, in a lengthy analysis of possible ways to keep tidal water out of Bethany.
The result of that data: A bladder dam at the mouth of the Loop Canal would raise the water in the Assawoman by more than a foot. Again, not a result that the state or federal officials the Town would need to help approve and fund such a project would be happy with.
Bladder dams at the north and south ends of the Assawoman Canal might seem like they could prevent flood waters from going into the Assawoman, but Graviet pointed out that, at the south end of the canal, there are no strongly vertical banks to prevent the water from just flowing out onto the land and then back into the canal on the other side.
Dredging the Salt Pond might seem like it would create more room for more water volume, but Graviet said their data showed it wouldn’t reduce the volume of water entering Bethany.
“So, we’re sort of back to where we were,” Graviet said, looking at projects that would have a “minimal impact, even on a five-year event. … “It’s not a rosy picture, but this is flooding in Bethany Beach from [the Town’s] perspective,” he concluded.
Graviet noted that, while the Corps had concluded its study before it was fully completed due to having run out of funding, the Town could, if it wished to pursue things further, task engineers with picking up where the Corps left off. But the Corps’ findings don’t suggest that would offer an easy, or inexpensive, solution — or perhaps any feasible solution at all.
Asked about the potential to install tidal gates at the inlet, Graviet stated with a chuckle, “I have not had the hubris to suggest that. They do have gates that large in Europe,” he noted before acknowledging that the tremendous speed of the water through the inlet would pose a problem for such a project.
“The cost would be astronomical. The political burden would be tremendous,” one BBLA member added.
Asked about the proposed Mews at Bethany project that requests to fill in some existing wetlands in exchange for wetlands being created west of the town, Graviet said anything that reduces the ability of the land in Bethany to absorb water just causes more problems, as does “anything that doesn’t let water move where it’s being moved today.”
Graviet confirmed that flooding does seem to be hitting Bethany harder than the neighboring towns of Rehoboth Beach or Fenwick Island.
“We pick up more damage than surrounding communities,” he said, noting that Rehoboth doesn’t back up to tidal waterways and has a higher overall elevation.
Former Mayor Jack Walsh asked Graviet whether he felt it was reasonable to consider only aiming the Town’s efforts at improving rainfall-related flooding, to prioritize its efforts, realizing that tidal flooding “is beyond our capability” to address.
Graviet said the Town had focused its resources into moving rainwater. “We can enhance runoff, but anything that overflows into the Loop pushes back into the town.” He questioned whether the Town should spend $500,000 on an underground pipe to improve stormwater runoff, if tidal waters are just going to continue to flow into the town.
Asked about the seemingly ever-increasing amount of impervious surface in the town, Graviet emphasized that the Town doesn’t let anyone cover a ditch “unless there’s a substantive reason. And if someone wants to enclose a ditch, it’s scrutinized.”
“The Planning Commission has wrestled with improving [impervious surface] for years. They haven’t come up with a resolution they felt would satisfy the home owner or the developer.”
He noted that the Town, acknowledging that it is full of water, does spray a larvacide for mosquitos and had started this summer’s spraying the prior Wednesday. “We doubled the amount of chemicals purchased this year, in case we run into a problem,” he said.
“But no matter what we do with the swales…” he began, gesturing to the map of oft-flooded areas that make up most of the town.
Beach replenishment waiting until next year
Also at the June 18 meeting of the BBLA, Graviet and BBLA President Tracy Mulligan offered a brief update on the state of the town’s beaches, which were hard hit by nor’easters over the fall and winter.
Graviet said DNREC and Philadelphia-based Corps officials had “expected the Corps to fund [replenishment in] Bethany and South Bethany, and were quite surprised when that funding wasn’t there” in the Corps budget proposal.
He said U.S. Sen. Tom Carper (D-Del.) had gone back to the Corps, asking that money set aside for recovery from Hurricane Sandy in communities where local officials hadn’t yet been able to obtain the easements needed to do the work be reallocated for beach replenishment in Bethany. He said Carper hadn’t gotten a response to the request.
“We were hit worse than Rehoboth and Dewey,” Graviet acknowledged, but replenishment hadn’t been planned in the town this year, while it had been in Rehoboth and Dewey. “It’s planned next year, contingent on funding,” he emphasized.
He said that the State has been moving sand in Bethany to try to adapt to current conditions and has been “tremendously responsive” to the Town.
Graviet noted that what was at one time only 80 feet of beach has now increased to 320 feet, making it likely that the Town will be able to have its Fourth of July fireworks show shot from the beach again.
He acknowledged that the Town had been forced to leave its accessibility-enhancing Mobi Mats off some of the east sides of the dune crossings at the south end of town, due to the loss of sand there. And where dunes areas were lost, he said, the Town was forced to put in steps, which have to be removable for storms, with no anchors or concrete and no pilings. They just sit on the sand.
“They have a rise of 5 inches, to make them as easy to negotiate as possible,” he said, but they could not build ramps with turns, due to the support structure that would be needed.
Graviet also told property owners at the meeting to expect a survey coming to them in the coming weeks on the detailed design for the so-called “Central Park” on the former Christian Church/Neff properties at the northwest corner of Routes 1 and 26.
The initial survey in 2014 had led to development of initial plans and features, he noted, and the upcoming survey will help define exactly what will go into the park, such as earth mounding, trellises for shade, a small open pavilion suitable for a wedding or similar limited uses, as well as screening of neighboring residential property.
Information on the preliminary design concepts is available on the Town website, or the Town will mail it at citizens’ requests.
Asked about whether the park would have restrooms, he noted past opposition to structures being built in the park, but he said if the need was established, the Town might put in temporary restrooms on a seasonal basis.
Finally, Graviet addressed new speed bumps installed on Gibson, noting that the “milder” ones installed previously near the stop signs had led to virtually no falloff in the through traffic they were meant to discourage and also to people no longer stopping at the stop signs, but rather just rolling slowly through.
With two “very serious” speed bumps now installed 90 feet away, “Now, if you don’t stop, you’re going to have problems,” he said. He acknowledged some complaints about the noise the bumps generate but said the Town was looking for feedback from the neighbors, who had first raised concerns about the heavy cut-through traffic on the road but had been split about 60/40 on whether they wanted new speed bumps there.
“We’re measuring the traffic,” he said, and “We hope it will fall off to almost nothing.”