The Army Corps of Engineers this week will begin dredging the shipping channel in Portland Harbor, a $9 million project that will remove up to 500,000 cubic yards of sediment and assure depths of 35 feet at mean low tide.

This is the first maintenance dredging of the channel in 15 years, and the work will include drilling through ledge at five high spots in the channel and setting off underwater explosives.

The project is critical because the channel is slowly filling in with sediment, particularly at the edges, said Mark Klopp, president Portland Pilots. The dredging will allow ships to sit lower in the water and carry more cargo, which improves efficiency and saves money, he said.

“It puts everything back to normal,” Klopp said.

In preparation for the dredging, crews since December have been removing lobsters from the harbor and taking them to an undisclosed location on the other side of Fort Gorges. Crews will continue removing lobsters throughout the dredging project, which by state law must be completed by March 15 to avoid interfering with the lobster fishery, which begins in the spring.

The federally funded dredging project was supposed to begin on Nov. 1 but has been delayed because of cold weather conditions that the contractor, Cashman Dredging of Quincy, Mass., encountered at a project in New Haven and Norwalk, Conn., said Dick Ingalls, a South Portland resident who serves on the Maine Port Authority board of directors.

Advertisement

“We are anxiously waiting for them to come,” Ingalls said. “We don’t want to be moving all these lobsters for nothing.”

On Monday, a fleet of Cashman vessels will depart from New Haven and sail to Portland, said Norman Bourque, project manager for Cashman Dredging. The fleet includes a drilling and blasting rig, a dredge with a crane and bucket, a split-hull hopper barge that will carry the sediment to a dump site at sea, and several tugboats

Bourque will be in Portland on Monday. He said the vessels will arrive in Portland in the middle of the week, and work may start Thursday.

The company’s dredge, the Dale Pyatt, is believed to be the largest of its kind in the nation, according to The Boston Globe. It is equipped with a crane and two huge clamshell-shaped attachments for scooping up sediment. A clamshell scoop digs from two directions, trapping mud and waste in between. The barge has living quarters for up to nine people.

While the Dale Pyatt begins dredging the channel in the upper part of the Fore River near the Veterans Memorial Bridge, crews will begin drilling holes in the ledges located in the channel between DiMillo’s floating restaurant and the Coast Guard Base in South Portland, Ingalls said.

The holes will be packed with explosives. Because the explosions will occur 35 feet below the surface of the water, the public won’t see or hear much, except for bubbles, said Lance Hanna, deputy harbor master.

Advertisement

The sediment will be dumped in a disposal area located 7.1 miles east of Dyer Point in Cape Elizabeth.

Hanna and Portland lobsterman and commercial diver Jim Buxton have been removing lobsters from the harbor, a project budgeted at $90,000 and paid for by the cities of Portland and South Portland and the Maine Port Authority.

The two men are laying 300 traps in a grid pattern, starting upriver and moving toward the mouth of the harbor. They use special traps that allow them to catch juvenile lobsters. Because lobsters in winter travel to deeper, warmer waters, the men haven’t captured that many.

As of Jan. 27, they had captured 62 lobsters, 28,219 green crabs, 10,857 sand crabs, 169 Jonah crabs and two snow crabs.

The green crabs, an invasive species, are being dumped into a barrel. After they are dead, their bodies are dumped offshore.

Once the harbor is cleared of lobsters, Hanna and Buxton plan to set all their traps in a line at the mouth of the harbor to prevent any of the removed lobsters from crawling back into the harbor.

Advertisement

“It will be a wall of traps,” Hanna said. “We will be catching anything that moves.”

The shipping channel in the outer harbor, from Spring Point Ledge Lighthouse to Portland Head Light, is 47.5 feet deep at mean low tide. That channel has been dredged by private industry, but it’s easy to maintain those depths because the tides are strong there, Klopp said.

“That part of the channel flushes itself real well,” he said.

Tom Bell can be contacted at 791-6369 or at:

tbell@pressherald.com

 


Only subscribers are eligible to post comments. Please subscribe or login first for digital access. Here’s why.

Use the form below to reset your password. When you've submitted your account email, we will send an email with a reset code.