PLUM ISLAND — Boaters going in and out of the Merrimack River over the next few weeks will be sharing the water with a giant dredge that is clearing the channel, and they will need to know how to safely navigate around the behemoth.
Great Lakes Dredge & Dock Co. of Oak Brook, Ill., is dredging the channel and depositing the sand directly onto portions of Salisbury Beach and Plum Island, operating under a $5.5 million contract with the U.S. Army Corps of Engineers.
Great Lakes site manager Jenna Libby has prepared some tips on what to watch for when traveling through the channel.
A vessel involved in dredging that has an obstruction on one side — such as pipe lines, suction lines or a cutter arm — will warn approaching vessels away from the obstruction by displaying two black balls on that side during the day, one over the other. At night, the vessel will show two all-around red lights in a vertical line.
On the opposite side, if there is no obstruction, the dredge would show two diamond shapes during the day, one over the other. At night, the vessel will show two all-around green lights in a vertical line as an indication that this is the safe side to pass.
The dredge operating in the Merrimack River channel, the 320-foot Illinois, will be moving among five separate anchors. The position of each anchor will be marked with a buoy with flashing amber lights, Libby wrote.
Boaters "will see the dredge slowly swinging back and forth in a 200-foot arc as it is digging," Libby wrote.
Behind the dredge is a high-pressure discharge line that starts with 1,700 feet of floating 30-inch diameter rubber hose attached to 3,000 feet of submerged pipe. The floating line will be marked every 120 feet by flashing amber lights. There will be a red light at the end of the floating line, where it attaches to the submerged section.
Boats should remain south of the marker lights when entering or leaving the river.
NJ Man Charged With Murder in Death of Patz
Support, Fun for Kids of Fallen Soldiers at Camp
Fugitive Penguin Caught, Returned to Aquarium
50 Years Later, Underground Fire Still Burning
Light Show Transforms Sydney Opera House
Raw Video: Unruly Passenger Restrained in Miami
Raw Video: Robber Uses Drive-thru Window
Raw Video: Dragon Arrives at Space Station
Calif.'s Coronado Named Nation's Best Beach
CEO Salaries Become Sore Issue in Labor Disputes
Raw Video: Fight Erupts in Ukrainian Parliament
Texan Ranchers Remain Wary of Drought
Raw Video: Soldiers Plant Flags at Arlington
Police: Man Arrested in Etan Patz Disappearance
NYC Protests: the Revolution Will Be Scripted
Chicago U.S. Attorney Fitzgerald Resigns
Neighbors of Etan Patz's Suspect: It's Shocking
Gulf Fishermen Reel From Seafood Troubles
Stuntman Makes Skydive Without Parachute in UK
Raw Video: Bride Who Faked Cancer Released
