© Parks CanadaShelley Humphries, Parks Canada aquatics specialist, assesses and works to clean up a mysterious contaminant at Moraine Lake in Banff National Park on Friday, September 21.
But a section of the pristine lake near the village of Lake Louise took on an shade of lime green Friday when an unknown contaminant was found in it.
Visitors and parks officials alike were wondering what was floating on the lake's surface.
"It was mysterious," said Shelley Humphries, an aquatics specialist with Banff, Yoho and Kootenay national parks. "We're still not sure what it is."
The substance, which was quickly contained by booms, was collected and taken to a federal lab for testing.
"If it's what we suspect it is, it's not toxic," said Humphries, noting it looks like fluorescent tracer dye that's often used for industrial or ecological purposes. "I don't know if this was an accident or if someone was curious about what would happen, but we're taking it very seriously."
The incident diverted half a dozen Parks Canada staff to the lake to deal with the issue.
It also led to the closure of the canoe operations on the lake for the afternoon.
Marta Cyperling, a Calgarian who was visiting Moraine Lake, said they had to change their plans Friday when they couldn't canoe on the lake.
"Our reaction was, what is that and who would dump that here?" she said. "To actually dump a chemical into such a pristine lake, we wondered who would do that.
"I am glad that they are taking it seriously," Cyperling added.
The lake is home to the threatened cutthroat trout and there are many other wildlife - including grizzly bears, which are also on the province's list of threatened species - in the immediate area.
So far, there have been no reports of animals in distress.
Test results on the substance are expected back in the next couple of days.
If anyone has any information related to the incident, they are asked to call Parks Canada at 1-888-WARDENS (1-888-927-3367).
it looks like anti-freeze to me...