Jan. 05–With daytime temperatures in the single digits and wind chills that plunge below zero, just getting to work or shoveling a driveway is hard enough for most people.
So, imagine what it’s like to spend seven hours working on the concrete walls of a lock along a frozen river with nothing to block the wind or, worse yet, 15 feet below the water line in a tunnel under a lock that regularly floods.
That’s what goes on along the region’s rivers at the locks and dams maintained by the Army Corps of Engineers. It’s winter maintenance season for the Corps, and the frigid weather has them fighting a continual battle against river ice.
“We like to say that our operators have the luxury of working outdoors during the summer,” said Ian McKelvey, the Corps’ supervisor of operation specialists on the Allegheny River.
“But it’s in the winter when they earn their keep,” he said. “Imagine being out there now for seven hours dealing with ice issues at the lock gates?”
But deal they do, albeit a little slower, getting the job done, McKelvey said.
Ice covers much of the Allegheny River in Armstrong and Allegheny counties, with 4 to 6 inches of snow atop that north of Ford City.
The Corps’ workers have a twofold job: keeping locks free of ice so they remain operable through the winter and keeping an eye on the ice itself for signs of ice damming that could spell flooding trouble when the weather warms.
Although the arctic cold snap blanketing the region had river ice forming faster than usual, there are no major problems on any of the rivers yet, said Lt. Shawn Simeral with the Coast Guard in Pittsburgh.
He participated in a conference call Wednesday on the condition of the rivers with river-based industry representatives and the National Weather Service.
“A lot of industry vessels are limiting tow sizes and are slowing down their movement in the water for safety reasons,” he said.
Formation of the ice on local waterways is not surprising.
However, what is not so well-known are the dangers posed by ice and the substantial amount of maintenance for outdoor water facilities such as locks on the Allegheny, Monongahela and Ohio rivers.
As most of humanity hunkers down indoors waiting for double-digit temperatures to return, workers at the region’s river locks are clearing ice, sometimes on an hourly basis, to keep the facilities open and ready for business.
Locking through ice
Working barges and moving water shear the sheets of ice on area rivers, reopening the navigation channels. The remnants float, spill over the fixed-crest dams and drift quickly on their migration downstream.
A hardy bunch of workers toils to keep the ice out of the river locks, which are used by commercial boat traffic.
The ice, though, can double the time it takes for commercial traffic to pass through a river lock. It’s called a “double lockage.”
Sometimes when a barge needs to lock through, the ice pushed by the vessel accumulates in front of it as it cuts through the water to reach the lock chamber.
That forces lock operators to make the barge wait while they lock through the ice to get it out of the way.
To keep ice from forming inside the locks, the Corps operates “water movers” that circulate water inside the lock chambers to keep it from freezing.
Under the lock
But ice isn’t just a problem on the rivers’ surfaces.
Deep inside lock facilities are tunnels, called “galleries,” that house hydraulic, air and electric lines used to operate the lock gates. The tunnels have their own gates, allowing them to flood — by design.
During winter months, the galleries are drained so workers can perform work on the lines in them — and shovel out the ice that can accumulate there.
Such was the case this week at Lock and Dam No. 7 near Kittanning, where mechanic James Burford was cleaning out the gallery and replacing rusted hydraulic pipe. A top priority also are the air lines, which are used to send a continuous flow of bubbles around the lock gates so ice can’t form around them.
Without the bubbles, the ice could make the gates inoperable, stopping commercial traffic along the rivers.
Mary Ann Thomas is a Tribune-Review staff writer. Reach her at 724-226-4691, firstname.lastname@example.org or via Twitter @MaThomas_Trib.