Several days ago we told you that Lake Erie’s bottom water temperatures had reached below the magic number of 39.2°F, meaning the surface could freeze as long as the air temperature above the lake stayed below freezing.
In case you haven’t been outside lately, the air temperature is definitely freezing.
As a result, ice has started to form on Lake Erie. This map shows that as of January 21, ice coverage is concentrated on the shallow areas of the lake's western basin and shorelines.
As of January 22, the water coming into our Morgan Water Treatment Plant is a chilly 33.9°F (1.1°C). Meanwhile, it looks like forecasted temperatures will remain cold enough to keep dropping the surface water temperature, allowing ice coverage to grow.
Many Great Lakes ecosystems depend on ice coverage. Plankton are more resilient when protected by a layer of ice, for example. But the amount of ice coverage can have both positive and negative impacts. Last winter, over 90% of Lake Erie’s surface was covered in ice. The extensive coverage was a hindrance for shipping but a boon for ice fishing.
What does ice cover mean for your drinking water?
Our raw water intakes, which take water from Lake Erie to our treatment plants, are located deep enough and far enough from shore that ice formation doesn’t impact our ability to get water.
Ice coverage does mean that waters that would normally churn from wind are instead calm, decreasing turbidity - a measure of the cloudiness of the water. So the water coming into our treatment plants is clearer, requiring fewer adjustments in the treatment process in order to deliver the same high-quality product to your tap.
To get your daily dose of Great Lakes ice data while the NOAA GLERL website is unavailable, check out data maintained by our friends to the North: https://iceweb1.cis.ec.gc.ca/Prod/page2.xhtml?CanID=11080&lang=en&title=Great+Lakes or the U.S. National Ice Center: https://www.natice.noaa.gov/products/great_lakes.html.