Source Information
Durham Region Health Department monitors recreational water quality at sites in this region. The sampling season starts on June 5th and ends on August 28, 2023. Water at all sites is sampled for E. coli and Total coliforms. Water samples are collected weekly on Mondays or Tuesdays. Results are posted to Swim Guide as soon as lab results are available (typically the Friday after sampling). Durham Region Health Department issues beach advisories when the geometric mean concentration of at least five samples is above 200 E. coli / 100 mL of water or when a single sample is above 400 E. coli / 100 mL of water. This guideline comes from Canada’s Guidelines for Canadian Recreational Water Quality (2012). It is applied to beaches in Ontario in accordance with Ontario’s Recreational Water Protocol, 2018.
In Swim Guide, a beach is marked Green when the geometric mean of at least 5 samples is below 200 E.coli / 100 mL water and each individual sample concentration are below 400 E.coli / 100 mL. A beach is marked Red when the results are equal to or above a geometric mean of 200 E.coli / 100 mL water and/or 400 E.coli / 100mL. A beach is marked Grey when there are no current results or there is no available information. The Ministry of the Environment F-5-5 Procedure says that a clean beach is open at least 95% of the swimming season, even if it is near a sewage pipe or combined sewer outfall. This rule applies to every place that is public, accessible, and feels like a good place to swim. When all else fails, the Ontario Environmental Protection Act strongly states that no one can interfere with the use that you can make of a public waterway - like swimming! DISCLAIMER: Historical data from 2017 and prior reflect the previous Ontario standard of a geometric mean of 100 E. coli /100 mL. Historical data from 2018 onward reflect the new Ontario Operational Approaches for Recreational Water Guideline, 2018: Geometric mean concentration 200 E. coli/ 100 mL and single-sample maximum concentration of 400 E. coli /100 mL.
