The Burlington Department of Public Works says operator error caused about 2.5 million gallons of untreated sewage and stormwater to flow into Lake Champlain.
The "operator-induced equipment failure" happened Wednesday morning.
The department’s assistant director for water quality Laurie Adams, says pumps that add chlorine to raw sewage didn’t work between 6 and about 7:30 in the morning.
She says the health risks are uncertain but says there’s likely to be minimal human contact because of the cool temperature of the lake which is now at around 38 degrees. She told the Burlington Free Press it would be a much bigger concern if this happened in the summer when more people use the lake for recreation.