Two federal agencies are considering a mammoth wetlands restoration project that would use mud dredged from Chesapeake Bay shipping channels to undo 60 years of erosion at Blackwater National Wildlife Refuge - a task that would cost hundreds of millions of dollars.
The U.S. Fish and Wildlife Service and the Army Corps of Engineers say they would like to rebuild 8,000 acres of marsh at the 24,000-acre refuge on the Eastern Shore. The proposal is included in a 20-year management plan that outlines how the corps would handle the more than 3 million cubic tons of dredge spoils that must be removed each year to keep the port of Baltimore operating.
"The bottom line is that we haven't been funded for any of this at Blackwater, but we think now is the time to explore the possibilities," said Scott Johnson, of the Corps of Engineers office that oversees dredging in the bay. "The costs would be high, but the environmental benefits are so high we need to take a look at the feasibility."
State and federal agencies plan to spend $400 million during the next decade to restore 1,140 acres lost to erosion on Poplar Island in the Chesapeake Bay off Talbot County. That project is due for completion in 2014.
A broad environmental impact study by the corps identified Blackwater in Dorchester County as one of three potential new sites for clean dredge material. Also included was a site at the James and Barren islands near the Little Choptank River in Dorchester, which have suffered from extensive erosion. Expanding the Poplar Island restoration is a third possibility.
Cost estimates have not been completed for any of the sites, said Mark Mendelsohn, a planner in the corps' Baltimore office. All three sites would have to undergo lengthy environmental reviews, he said.
Rep. Wayne T. Gilchrest, a Republican who represents the Eastern Shore, said he believes federal budget problems could make the dredging projects a hard sell on Capitol Hill.
"We're working with the Army Corps of Engineers on a number of projects to address shoreline erosion on both public and private land, and Blackwater is an important part of that," Gilchrest said. "Given the fiscal realities of the federal budget, though, funding for these types of projects is always a challenge."
The next step for the Blackwater proposal would be a three- to five-year feasibility study that would cost as much as $6 million, said Dixie Birch, supervisor of wildlife biology for the Fish and Wildlife Service. "Potentially, we have the capacity to handle dredge material here for as long as 50 years, but all the details, the logistics and the cost would have to be worked out," Birch said.
Unlike Poplar Island, where engineers designed huge dikes to hold dredge material that will reshape the island, adding land to Blackwater's shallow bays and rivulets would be more difficult. Dredge material would have to be pumped as far as five to 10 miles. One possibility would be to use James or Barren island as a staging area for pumping silt to Blackwater, Birch said.
Officials at the refuge say small-scale marsh restoration projects they have completed in the past offer a hint of what could be possible at Blackwater.
Two years ago, the corps, the wildlife service and the state Department of Natural Resources completed a $1 million pilot project that restored 15 acres of marsh, taking silt from throughout the refuge and pumping it along the edges of existing marsh. In the early 1980s, employees restored about 12 acres of marsh.
Blackwater officials say the preserve is ready for restoration now that they have eliminated nutria, the non-native water rodents that were responsible for destroying thousands of acres of marsh.
The animals, which cause erosion by eating the roots of marsh grasses, were eliminated in a high-tech, $2-million hunting and trapping effort. After killing nearly 9,600 of the animals, officials are debating how to keep them from coming back.
Restoration of Blackwater's marshes, wildlife experts say, is important to tens of thousands of migratory waterfowl that winter in and around the refuge, as well as for other animals, including the endangered Delmarva fox squirrel.
"It's not a new idea, but it has never been done on this kind of scale," Johnson said.