LEWISTON — Watershed officials hope to have some answers soon as to what caused a fish-killing algae bloom in Lake Auburn over the summer.
The Lake Auburn Watershed Protection Commission will host a public hearing Feb. 13 to discuss engineering reports on what was behind the algae bloom.
“It’s the diagnostic end of the studies, looking at the water quality,” said Lynne Richard, Lake Auburn Watershed education and outreach manager. “If there are issues, what can we do about it? The step after that is what we can do, but right now we need to get those reports.”
The meeting is scheduled to begin at 5 p.m. in Lewiston City Hall.
“We’ve gone through the entire watershed, looking at the various inputs to the lake,” she said. “We’ve been examining where water quality issues might be coming from and where might we be getting excess nutrients or are there erosions and what might be adding to the issues in the lake.”
Richard said the watershed commission has not received any reports yet, but expects them by the end of January.
Water quality officials discovered more than 50 dead trout along the shore or floating close to the shore in mid-September. The largest discovered was a 36-inch trout weighing between 15 and 20 pounds. The other fish averaged around 22 inches long.
Officials blamed an algae bloom for killing the fish. They said that warm early spring temperatures extended the algae growing season and hot summer temperatures supercharged it. Combined with heavy June rain storms that eroded soil around the lake and brought phosphorus rich soils into the water, the algae had optimum growth.
As the algae grows and dies, it sinks into the lake, decaying and using up oxygen in the process.
That layer of the lake, where the lake trout live, is already low in oxygen late in the summer. The decaying algae used up available oxygen, suffocating the lake trout.
Studies are being done by local water quality staff and by consultants from Massachusetts-based CDM Smith, the Maine Volunteer Lake Monitoring Program, the Maine Department of Environmental Protection and Bates College.