WELLFLEET – The most recent plans for the Herring River restoration project include a new bridge, two new upstream dikes, increased elevation of three roads, a road redesign and about two dozen structures like berms to protect private property in its capital construction plans.

The largest salt marsh restoration project from Maine to New York covers 1,100 acres in Wellfleet and Truro. The river extends from Wellfleet Harbor northeast for nearly 4 miles, and about 80 percent of the river’s flood plain is within the boundary of the Cape Cod National Seashore.

Early estimates project the cost at $30 million to $40 million.

The project, begun in 2005, is meant to reverse the drying-out effects of the Chequessett Neck Road dike, built in 1909 at the mouth of the river. The restoration will improve water quality and fish habitat throughout the flood plain, restore native species, reduce mosquitoes and build up the marsh to better protect it against sea level rise, according to the draft environmental impact statement.

The final environmental impact statement, in compliance with the National Environmental Policy Act, is expected to be completed in early 2015, according to project coordinator Margo Fenn. The towns of Truro and Wellfleet, along with the National Park Service, are working on a third memorandum of agreement to determine how the project construction and implementation will be handled.

On Oct. 14, state and federal officials announced that the project was nearing the end of the overall design phase and moving into a permit-seeking phase, with the help of a new infusion of state and federal funds. The National Oceanic and Atmospheric Administration gave the project $300,000 in 2013 and $752,000 this year, as part of a planned $3 million grant, according to project records. State officials announced a $612,000 grant Oct. 14 as part of a $10 million target.

The project’s overall design phase includes a new bridge with tide gates to replace the existing town-owned bridge at Chequessett Neck Road in Wellfleet. It also calls for new dikes and tide gates at Mill Creek and at Pole Dike Creek, both to protect private properties in Wellfleet. Old County Road, Pole Dike Creek Road and Bound Brook Island Road, all in Wellfleet, are scheduled to be raised as needed. High Toss Road, a public way in Wellfleet that is owned by the National Park Service, is scheduled to be redesigned to remove a section of the road that impedes the river’s flow upstream.

Also, property-specific protections like berms, new wells and raised driveways are planned for as many as 29 private properties in Wellfleet that have structures that would be affected by the rising tides. Project proponents are negotiating with the Chequessett Yacht & Country Club in Wellfleet about raising some low-lying fairways, and if an agreement is reached, that construction would become part of the project as well.

Overall, about 375 private properties are within the salt marsh restoration area.

The total cost of the capital construction plans will not be determined until the designs are finalized, Fenn and Friends of Herring River board president Don Palladino said. The town of Wellfleet would not be asked to pay for anything except in-kind services, Fenn and Palladino said.

The nonprofit Friends of Herring River is acting as a contract manager for the project.

“The project will seek funding through a number of federal, state and private funding sources,” Fenn said.

There will be some opportunities for the public to participate in the capital construction plans, according to Wellfleet Town Administrator Harry Terkanian and Cape Cod National Seashore Superintendent George Price.

Any changes to a public road layout or any appropriation of town money required for changes to a public road would need to go before Wellfleet town meeting, Terkanian said. Elevating public roads, without changing the layout, can be approved without a town meeting vote but would ideally involve the town Public Works Department and the Board of Selectmen, Terkanian said.

The new bridge planned at Chequessett Neck Road might go before town meeting, depending on the final design and whether the road layout is changed, Terkanian said.

High Toss Road is the more complicated road change. The dirt road is used largely by hunters, walkers, horseback riders and other recreational users to reach Griffin Island and other areas along Cape Cod Bay in the Seashore. Those users and other citizens will have a chance to comment on how the road would be redesigned, Fenn said.

“High Toss Road is an impediment,” Price said, referring to blockage of natural tidal flows caused by a section of the road. “There’s a possibility it could be demolished or removed and the fill used elsewhere. There’s no reason for the road to exist for Park Service purposes. However, if the town has a concern and wants to maintain it as a road or together we want to maintain pedestrian access, we would support those desires.”

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