Flood Risk Category Definitions

Risk CategoryDescription
Below Summer Minimum
  • Boating and recreational access are limited.
  • Winter Operations: Water is lowered to prevent ice damage and capture spring snowmelt.
At Summer Water Level
  • Standard operational levels.
  • No flooding occurs.
Above Summer Maximum
  • Elevated Water Levels.
  • No flooding occurs.
Action Stage
  • Water levels rise to approach the top of banks in low-lying areas.
  • No flooding occurs.
  • Serves as a flood watch for communities to monitor conditions.
Minor Flooding
  • Localized inundation begins in isolated or low-lying areas.
  • An entire lake Slow-No-Wake Order is likely issued.
Moderate Flooding
  • Structures are threatened; water may enter buildings without sandbagging.
  • Road closures are expected.
  • High lake levels slow down storm sewers, increasing urban flash flood risks.
Major Flooding
  • Significant water entry into buildings is imminent.
  • Widespread road closures and travel disruptions.
  • Evacuations are likely. Extreme urban flash flood risk.

Current Water Levels and Flood Risks