HomeMy WebLinkAbout2017CorneliaBlueGreenAlgae
City of Edina 4801 W. 50th St. Edina, MN 55424
Contact: Kaylin Eidsness, Senior Communications Coordinator Phone 952-833-9537 Fax 952-826-0389 EdinaMN.gov
FOR IMMEDIATE RELEASE
High Algal Toxin Levels Detected in Lake Cornelia
Edina, Minn., Aug. 17, 2017 – The City of Edina and the Nine Mile Creek Watershed District have
detected high Microcystin toxin levels in Lake Cornelia and are urging residents to avoid contact with the
water due to public health concerns.
High blue-green algae levels were measured in recent samples by the Nine Mile Creek Watershed District.
High Microcystin levels are typical with excess growth of blue-green algae. Follow-up toxicity monitoring was
done to evaluate public health risk. The latest data indicates current Microcystin levels present a public health
risk. High Microcystin toxin levels were also detected in the lake last September.
Exposure to Microcystins may harm the liver and be harmful to kidneys and, in extreme cases, death.
Symptoms of poisoning include jaundice, shock, abdominal pain/distention, weakness, nausea and vomiting,
severe thirst and rapid or weak pulse. If you begin to notice symptoms in you or another person, contact your
health care provider; in animals, contact your veterinarian. People and pets should not come into contact with
the water until they are notified that it is safe.
Blue-green algae are a type of cyanobacteria present at low levels in many Minnesota lakes and ponds. When
water is stagnant, warm and rich in nutrients – especially phosphorus – cyanobacteria can grow quickly,
forming “blooms.” These blooms typically look like pea soup or bright green paint. They can produce a strong,
swampy odor as the cyanobacteria breaks down.
“The City is working to minimize invasive aquatic plants in Lake Cornelia and promote the growth of a healthy
native aquatic plant population to ‘tie-up’ phosphorus, making less of it available for cyanobacteria and other
algae to grow,” said City of Edina Water Resources Coordinator Jessica Vanderwerff Wilson.
According to Nine Mile Creek Watershed District Education and Outreach Program Manager Erica
Sniegowski, this is a common urban water quality issue. “Our infrastructure was designed to collect runoff
from streets. This runoff flows untreated to local bodies of water. Pollutants gather in these areas and often
create high levels of phosphorus, which can lead to harmful algal blooms,” she said.
Lake Cornelia is treated for algae up to twice per year by lake management companies. Even after algae
treatments, residents should exercise caution. When cyanobacteria cells die, the toxins present in the cells
are released into surrounding waters. Some toxins are very stable and can remain in the water for days or
weeks after the bloom has disappeared. Once a toxin is in the water, it is generally not feasible to remove the
toxin from the lake and, hence, the toxin remains in the lake until it disappears naturally. Algal toxins
disappear naturally when they are broken down by bacteria and light. The time period of the breakdown
varies from a few days to several months.
The Watershed District will continue to monitor the lake until toxin levels drop.
For more information, contact Wilson at 952-826-0445 or Sniegowski at 952-358-2276.
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