Power Plant Resumes Operations After Youghiogheny River Fish
Kill
Pittsburgh Post-Gazette
5 October 2016
By Don Hopey
A small hydroelectric power operation at the Youghiogheny River
Dam in Confluence, Somerset County, resumed operation Tuesday
morning, a week after it was shut down and blamed for killing
about 230 brown and rainbow trout held in nursery pens below the
dam.
It was at least the third time the power plant has played a role
in the death of fish in the Yough Cage Nursery, a co-operative
trout rearing project of Chestnut Ridge Trout Unlimited and the
Pennsylvania Fish and Boat Commission, that has operated at the
base of the dam since the late 1990s.
The U.S. Army Corps of Engineers, which owns the flood control dam
and ordered the power plant to temporarily stop operations, said
its preliminary investigation determined the fish died when the
power plant’s water discharges became “supersaturated” with
nitrogen.
But Gregory Brant, project operator for D/R Hydro Co. of the 12
megawatt power plant owned by the Youghiogheny Hydropower
Authority, said its gauges showed nitrogen concentrations were in
the safe range, and instead attributed the kill to high water
temperatures that “stressed the fish,”and poor water circulation
due to the algae-caked rearing pens.
“We have a difference of opinion about the readings on the water
quality gauges,” Mr. Brant said. “This has happened at other times
in similar conditions in late summer, and there are procedures in
place to reduce the risk. But truthfully, there shouldn’t be fish
in those pens at this time of year. That just invites disaster.”
The high nitrogen concentrations usually occur in late summer when
the the hydroelectric power plant draws water low in oxygen from
the bottom of the dam’s lake. Releasing that water below the dam
would kill fish, so the power plant must add oxygen before it’s
released into the river below the dam.
It does that by either injecting liquid oxygen into the water — an
expensive process — or using blowers. But the atmospheric air
blown into the water contains about 20 percent oxygen and 80
percent nitrogen, Mr. Brant said. He said the power plant was
using a combination of liquid oxygen and blowers when the Corps
ordered it to shut down last week.
“We didn’t think anything was wrong until we got the order from
the Corps,” Mr. Brant said. “We’ve been in communication with the
Corps and will need to sit down and work out procedures on how to
handle this situation in the future.”
Dale Kotowski, president of Chestnut Ridge Trout Unlimited, said
the nursery gets about 10,000 fish a year from the state, raises
them and stocks them in the Youghiogheny river and other lakes and
streams in the region.
After the fish kill last week, chapter members emptied the nursery
cages, removing about 600 live trout and releasing them in the
river.
“The nursery functions as the canary in the coal mine to tell us
when things are going wrong with water quality in the river,” Mr.
Kotowski said. “This happened because gauges monitoring water
quality didn’t catch the high [nitrogen] gas levels quickly
enough.”
Investigations of the incident by both the state Fish and Boat
Commission and the Army Corps of Engineers are continuing. A
meeting to discuss findings of the investigations and solutions to
the nitrogen problem is scheduled for next week.
Youghiogheny Hydroelectric Authority holds a Federal Energy
Regulatory Commission license for the hydroelectric plant,
operated by D/R Hydro Co. since 1989. The plant has the capacity
to generate up to 12 megawatts of electricity per hour, enough to
service approximately 8,000 homes for a year.
Don Hopey: dhopey@post-gazette.com, 412-263-1983, or on Twitter
@donhopey