---- — SEABROOK — The massive dredging and beach replenishment operation that helped buy time for Plum Island is about to be repeated for Seabrook and Hampton beaches.
Starting next week, Hampton Harbor will be dredged, and the sand pumped directly onto Seabrook and Hampton beaches. The project will be undertaken by Southwind Construction Corp. of Evansville, Ind., and is expected to be completed in about three months, according to the Army Corps of Engineers, which is overseeing the project.
This is the second major dredging project undertaken in local waters by the Army Corps since 2010.
In late 2010, the Army Corps managed a similar project at the mouth of the Merrimack River. Sand was dredged from the sand-clogged river mouth in order to open up the navigation channel. About three-quarters of the sand was pumped onto Plum Island, and the rest onto Salisbury Beach. In both cases, the most vulnerable areas where erosion had imperiled homes were targeted.
The Hampton project is larger in scope than the Merrimack River project, according to Tim Dugan, a spokesman for the Army Corps. Some 172,000 cubic yards of material is expected to be dredged from Hampton Harbor, he said, compared to a little more than the 142,000 cubic yards that was dredged in the Merrimack River project.
The dredging will open up the sand-clogged entrance to the harbor, and deepen the navigation channel and mooring fields in the inner harbor. The navigation channels will be dug to a depth of 8 feet and the mooring fields to 6 feet.
Sand will be pumped directly onto the beaches and will be graded to create a gradual slope. The project also calls for the installation of about 800 feet of snowfencing along Seabrook Beach, which will help hold sand in place.
Hampton and Seabrook have not experienced the visually dramatic impacts of erosion that Plum Island has seen, such as homes being demolished due to eroded dunes. But Hampton and Seabrook have witnessed significant erosion, Dugan said.
“Being on the Atlantic Ocean, (the beach) tends to get pounded,” Dugan said.
One big difference in the projects is the pricetag, which was determined by the lowest bid.
The Hampton Harbor project will cost $3.16 million, while the smaller Merrimack River project cost $5.5 million. The projects have different contractors — Great Lakes Dredge & Dock Co. of Oak Brook, Ill., won the bid on the Merrimack River project, after the Army Corps was forced to delay the process and revise the project scope due to changes in the erosion patterns on the beach. Also, bids for the Plum Island project came in above the initial projected cost of about $3.6 million, which forced the Army Corps to extend the bidding process and seek more funds.