Beaver Lake was contaminated by algae, not sewage


A Steele County lake initially thought to be contaminated by a suspected sewage spill is actually full of harmful algal blooms.

Steele County officials had reported that 5,000 gallons of sewage spilled into Beaver Lake earlier this week, but after removing water and taking samples, the Minnesota Pollution Control Agency investigators found that the pollution of the lake is actually being caused by algae, not sewage, according to a news release.

Even though it doesn't sound as gross, this kind of algae can be very harmful.

After examining the water, the MPCA said the algal blooms can pose health risks to people and animals if swallowed, and recommends that people avoid the algae and shore scum.

They also warned people prevent their pets from swimming in and drinking the water. In extreme cases, dogs and other animals have died after drinking other lake water containing these toxins.

The MPCA said scientists do not know what causes some algae to produce toxins while others do not, but that people should avoid contact with all severe blooms just in case.

The toxic blooms can be hard to distinguish from other types of algae. It's often described as looking like pea soup or spilled green paint, but can take other forms as well. Click here to learn more.

Right now, all that can be done is wait.

Once a bloom occurs, the only option is to wait for the weather to change — significant rainfall, wind shifts, or cooler temperatures — to disrupt the algae’s growth, according to the MPCA. In the long-run lake water quality can be improved by decreasing the amount of nutrients that runoff carries into lakes.

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