A plan to save Prime Hook National Wildlife Refuge from rising sea levels may do more than just create new habitat for migratory birds, increase opportunities for hunters, and prevent flooding in some coastal communities.
The ambitious proposal, released by the U.S. Fish and Wildlife Service on May 31, may become a template for how Delaware deals with the coastal flooding that already strikes the state’s many low-lying areas – a challenge that experts say will get far worse in coming decades.
The 10,000-acre Prime Hook preserve is one of the areas that state officials say will be virtually wiped out by the one-meter rise in ocean waters projected to happen by the end of the century if current trends continue.
Rising sea level is the main threat to the refuge and the main driver behind the federal agency’s long-awaited Comprehensive Conservation Plan.
As salt water from the Delaware Bay inundates some 4,000 acres of what had been freshwater impoundments, those areas no longer attract the migratory birds that they were built to shelter. The surging waters from the bay frequently flood the adjacent community of Prime Hook Beach and damage bordering farmland with salt water.
The plan lays out three options for responding to repeated flooding at the refuge. The option favored by the Fish and Wildlife Service would raise the level of at least one of the impoundments by about seven inches by pumping in million of tons of sand and mud from a long-planned dredging project to deepen the Delaware ship channel. The agency hopes the operation will allow the area to revert to salt marsh and drain into the bay rather than drawing waters from it, as it does now.
“The bay is rising twice as fast as the marsh is,” said Michael Stroeh, project leader for the Delaware Coastal Refuge Complex that includes Prime Hook and Bombay Hook refuges.
Stroeh said the Prime Hook plan could become a model for coastal restoration elsewhere because of its large size and because most other restoration projects, especially in the mid-Atlantic area, have not used dredging spoils to restore marshes.
"Any restoration project this large would be unique," he told DFM News. "It offers the opportunity for innovative ideas."
At a public meeting in Milford, Stroeh said the plan to dump dredging spoils at Prime Hook represents the best chance for the restoration project to succeed.
“The deepening project is my big shot to get sediment here,” he told residents at the meeting.
If approved, work wouldn’t begin until 2014 because the dredging spoils are earmarked for nearby Broadkill Beach and Kelly Island before that.
But the 102-mile dredging project -- designed to give larger cargo ships access to Wilmington and other ports on the Delaware – faces legal challenges from environmentalists who say the plan would disrupt the ecology of the Delaware Bay. Seventeen miles of the channel near Claymont has already been deepened.
If the plaintiffs win their lawsuit against the project’s leaders, the Army Corps of Engineers, that would halt work on the project, according to Jane Davenport, senior attorney for Delaware Riverkeeper Network, one of the environmental groups. The case is awaiting a ruling by the Third Circuit Court of Appeals in Philadelphia.
Davenport said any plan to dump dredging spoils at Prime Hook would be “extremely problematic” and would probably require the Army Corps to conduct another environmental impact statement before doing the work, a process that can take years.
Until the court rules, the Corps is pressing ahead and inviting bidders on the next phase of the project, according to Ed Voigt, a spokesman for the Corps in Philadelphia.
Voigt confirmed the Corps is talking to the federal wildlife service about using dredging spoils at Prime Hook. Any decision to take the material there would have to be funded by agencies other than the Corps, he said.
David Small, deputy secretary for Delaware’s Department of Natural Resources and Environmental Control (DNREC), said the work at Prime Hook could have value well beyond the central Delaware coast.
“Could that be a model that could be followed in other areas?” he asked in an interview with DFM News. “I think it could be.”
In April, DNREC released an assessment of Delaware’s vulnerability to sea-level rise. It estimated that 10 percent or more of the state’s land mass could be inundated by the end of the century. The agency’s coastal team is now working on how the state should adapt.
For now, there’s no immediate relief in sight for residents of Prime Hook Beach. They continue to endure frequent flooding of their yards, homes and streets as waters rush in to one of the impoundments on high tides, nor’easters, or major storms.
On June 4, a high tide flooded homes, ruined landscaping, and submerged Prime Hook Road, temporarily cutting off the community’s main link with the rest of the state. “This flooding every few months is very difficult for the people who own these homes,” said Cindy Miller, chair of the Prime Hook Beach Organization. “It’s traumatic and it’s a public safety issue.”
Miller said the community needs immediate relief from the flooding rather than the long-term solution proposed by the federal Fish and Wildlife Service. Her group will offer more detailed comments at a June 19 public meeting to discuss the Prime Hook plan.
The federal agency says restoring the salt marsh alongside the community of some 200 homes should eventually reduce exposure to the ocean waters that now sweep into the impoundment through several dune breaches to the north.
For now, the agency proposes to put sand, coconut logs, and Christmas trees along the east side of the impoundment in hopes that will break up the waves. The agency says it has no plans to close the dune breaches, because winds and waves would probably undo the work quickly, as happened after a previous repair in 2011.
The federal Fish and Wildlife Service is expected to make a final decision on Prime Hook by the end of the year.