PREPARED BY: Environmental Health

DATE: 2025-11-20

The Windsor-Essex County Health Unit (WECHU) conducts beach water sampling and testing in accordance with Recreational Water Protocol, 2019 and following the Operational Approaches for Recreational Water Guideline, 2018. Seasonal beach monitoring includes surveillance of water and weather conditions, and potential pollutants, as well as weekly water sampling to test for bacteria called Escherichia coli (E. coli).  These bacteria are found in the feces of people, as well as all warm-blooded animals and birds. 

High levels of E. coli in beach water can be caused by fecal contamination from some sources like animal waste, agricultural and stormwater runoffs as well as septic or sewage systems overflow. Exposure to elevated E. coli concentrations can cause severe stomach cramps, diarrhea, fever, and vomiting. 

To determine the water quality, the WECHU staff collect water samples weekly at local beaches. This year, seven beaches were sampled due to one public beach closure. 

DISCUSSION

The beach water monitoring program this year included weekly beach water testing and a predictive modeling program that provided daily water quality estimations for four participating beaches on weekdays. The results of the predictive modeling program will be presented at a future board meeting.

Beach water testing ran for a total of 14 weeks from May 28 to August 28, 2025. Weekly water samples were collected on Wednesdays to test for the harmful bacteria indicator E. coli. The results were updated weekly on Fridays for the public to access from the WECHU’s Beach Water Testing webpage and the Beach Hotline (ext. 1490).

Water quality warnings are issued when results are 201-999 E. coli/100ml, and beach closures are issued when results are equal to or greater than 1000 E. coli/100ml. This year, there were 25 water quality warnings issued and five beach closures during the season compared to 2024, which had 27 warnings and nine closures (Table 1 – see below).