The 2012 Great Lakes Water Quality Agreement states that “the Waters of the Great Lakes should allow for swimming and other recreational use, unrestricted by environmental quality concerns.”
The overall status of Beaches is Good and the trend is Unchanging to Improving. The Beaches indicator shows that many monitored beaches in the Great Lakes are safe for swimming and recreational use throughout most of the swimming season.
The U.S. and Canada use different E. coli criteria to determine when a beach is unsafe for swimming. Each year, over 700 beaches along the Great Lakes shoreline are monitored for E. coli as a measure of risk from fecal material contamination and these data are used in this assessment. Sources of E. coli can include overflow from wastewater treatment plants, runoff from the land, improperly working septic systems and even large flocks of waterbirds.
From 2018 to 2019, the percentage of days that monitored Canadian Great Lakes beaches met Ontario E. coli standards for swimming averaged 90% over this period. The U.S. Great Lakes beaches monitored from 2018 to 2019 were open and safe for swimming 94% of the time over this period. The status of monitored beaches was Good in all of the lakes other than Lake Erie. Lake Erie beaches in Canada and the U.S. were open and safe for swimming approximately 80% and 84% of the swimming season, respectively, resulting in a Fair assessment. The 10-year trend for Great Lakes U.S. beaches is Unchanging while the Canadian Great Lakes beaches are showing an Improving trend leading to an overall trend of Unchanging to Improving.