Posted on October 30, 2018
The big container ships and tankers will move in and out of Unalaska easier if the U.S. Army Corps of Engineers blasts and scoops 16 feet from the bottom near the Dutch Harbor Spit in a proposed $29 million project that’s at least four years away.
And bigger ships will be coming, even though that’s not the purpose of the project aimed at eliminating what is already a tight squeeze for cargo vessels loaded with fish and fuel moving across the rocky underwater reef.
“Our proposed project won’t accommodate anything deeper than what’s already coming to Dutch Harbor,” but it will allow the safer and more efficient movement of the vessels, fully loaded more often,” said Ronnie Barcak, project manager of the U.S. Army Corps of Engineers’ proposal dubbed the Unalaska (Dutch Harbor) Channel Navigation Improvements.
“Right now you can’t do 44-foot vessel safely or efficiently,” especially since 44 feet is the depth rating now, and the bar is 42 feet deep, according to Barcak, who said the ships now enter with less than full loads so as not to hit the bottom.
And often the ships have to wait offshore for waves and winds to lessen, to get in safely. The improvements will allow for operations 24 hours a day, seven days a week, he said.
But the study’s parameters are something of a technical point, because the deeper channel actually will mean bigger ships showing up, according to the city ports director and a marine pilot, in an era where ships are continually getting bigger to accommodate growing international trade.
“We’ve had lots of inquiries” from representatives of larger vessels now transiting the area on the Great Circle Route, between Asia and North America, said Unalaska Ports Director Peggy McLaughlin.
But another limiting factor will change if the bar is deepened, because the city will then dredge in front of its dock at the Unalaska Marine Center, from the present depth of 40 feet to 45 feet.
Presently, according to the Corps, only three docks in Unalaska can accommodate the big ships now: the UMC, also called the “city dock”, the American President Lines container terminal, and the Delta Western Fuel Dock, There are no plans for APL or Delta Western to deepen the water near their docks, according to the Corps.
“It’s a good thing for Dutch Harbor,” with ship sizes continually increasing, said Bill Gillespie, president of the Alaska Marine Pilots Association, which brings ships into local waters.
He said the proposed dredging is a positive step towards port modernization, and will help tankers that now transfer fuel onto fuel barges at anchor in Broad Bay, across the water from town.
“They’ll be able to bring tankers right straight to the dock on a more regular basis,” said Gillespie, who added that container ships now arrive “light loaded” to cross the bar in the nation’s top fishing port by volume where thousands of metric tons of frozen fish are loaded onto container ships and barges night and day.
The Corps’ team of dredging experts returned to Unalaska in October to update city officials and the public on dredging plans two years after their last visit on the proposed project endorsed by the Unalaska City Council.
The extra depth, if the U.S. Congress comes up with funding matched by the city, will allow the ships more maneuverability in the waters of Unalaska Bay in the eastern Aleutian Islands.
The project will require blasting prior to excavation, and hopefully with no explosive surprises from legacy military weapons in its ultimate quest to deepen the water level from 42 to 58 feet at the lowest average daily depth known to mariners as mean lower low water.
According to the Corps, the water really only needs deepening to 56 feet, but an extra two feet is added because it’s not always possible to dredge the bottom perfectly level, and the contractor, paid by the cubic yard, is happy to oblige by creating an extra two feet of clearance just in case.
The Corps want to see if 14 unidentified metallic objects are explosive by taking a closer took with an underwater remotely operated vehicle, before dredging the 600-by-600 foot underwater area, to deepen shallow water caused by a shoal from a moraine deposited by an ancient glacier just offshore of the Dutch Harbor Spit.
The one-year project would be completed at the earliest in 2022, if Congress approves the funding.
Unexploded munitions have been found in the area, left behind by the U.S. military during the Aleutian Campaign in World War II, and the Corps displayed photos of rusted landmines and projectile bombs previously encountered in local waters.
The 14 mysterious ferrous objects were detected with a metal-detecting gradiometer, which did identify abandoned crab pots by their familiar shape, while old military explosives might look like rusted globs of iron.
The shoal, commonly called a bar, is very hard and will first require loosening up with explosives packed into drill holes, and will require an “incidental harassment permit” because of the likely presence of marine mammals including sea lions, sea otters, seals and humpback whales.
There are so many marine mammals in the area that it would be impossible to blast the hard-packed underwater ridge without potentially impacting them, said George Kalli of the U.S. Army Corps of Engineers, saying the project couldn’t go forward without the federal environmental permits for disturbing marine mammals.
The dredging project is expected to require only a federal environmental assessment, and not a more detailed and time-consuming environmental impact statement, he said.
The public comment period on the proposed dredging project remains open through February of 2019.
The present cost estimate of $29 million is expected to change, Kalli said, though he couldn’t predict if the price would go up or down for the project that only affects large cargo vessels and not fishing boats.
The Corps held three community events during the recent visit by six federal employees from Anchorage.
Local resident Suzi Golodoff was concerned that the dredging of 16 feet of sea floor, from the present depth of 42 feet down to 58 feet, could cause erosion on the Front Beach along Bayview Avenue, where hers and other homes are located in the historic downtown area of Unalaska, by removing a natural underwater breakwater.
Corps officials said that was unlikely and that the project would have minimal impact on the Front Beach.
The route for the deeper channel was studied with a vessel movement simulator at the Corps’ research facility in Vicksburg, Miss., using a simulation of a container ship that stops in town regularly while sailing from the U.S. West Coast to Asia with seafood cargo, the APL Holland, as the Post Panamax “design vessel”, with input from two local marine pilots who participated in the indoor simulation exercises in an interactive movie theateresque high tech setting.
Barcak said 44 feet is only a “reference point” for ships that might draft between 40 and 48 feet, depending on the weight of the load.
The project would involve the removal of 182,000 cubic yards of material from the seafloor, and local resident Travis Swangel saw an opportunity to recycle the material for new landfill docks in Captains Bay, but Kalli said that would cost the government extra for the cost of barging the material, and suggested he’d get a better deal from a local quarry business, Bering Shai Rock and Gravel.
Corps officials are planning to dump the material elsewhere offshore near the bar, in deep water, spread out evenly on the bottom, although Vice Mayor Dennis Robinson said an underwater mound could create attractive new habitat where fish would congregate.
Source: Alaska Journal Commerce
