Encouraging results
The results of the samples taken in 2023 confirm that the water quality at the Gervais-Désourdy Nautical Centre is suitable for swimming with an average of 19 CFU/100 ml in dry weather. CFU (Colony Forming Units) are a measure of the concentration of E. Coli in the water. E. Coli are harmless fecal coliforms, but they are indicators of the possible presence of pathogenic microorganisms. The Canadian recommendation is that the geometric mean of bacterial counts in fresh water should not exceed 200 CFU/100 ml to be considered suitable for swimming. In the case of Chambly, this average is 61 CFU/100 ml.
A dry period corresponds to any day for which the precipitation of the last three days, including the current day, is less than 5 mm. However, during rainy weather, the water quality deteriorates and does not always allow swimming since wastewater overflows can temporarily contaminate waterways, as is the case in many places in Quebec.
The Chambly basin is popular with motorized and non-motorized water sports enthusiasts. In this regard, the study confirms that in dry weather, water quality standards for non-contact water activities (1,000 CFU/100 ml in Quebec) have always been respected, at both sites under study. In rainy weather, non-motorized water sports enthusiasts are protected given the closure of the Gervais-Désourdy Nautical Centre. In times of heavy rain over several days, caution is still advised before venturing into the basin and it is better to wait 48 hours after the rain has stopped before coming into contact with the water.
A study consistent with Chambly’s guidelines
In its 2022 Environmental Policy, the City of Chambly committed to monitoring water quality and facilitating access to it on its territory. The City monitored water quality in 2022 and 2023 through sample analyses carried out at the Gervais-Désourdy Nautical Centre and in front of the municipal wharf. It will continue on this path to ensure the safety of users, while continuing awareness and monitoring efforts to preserve this resource.
For a better sharing of the Richelieu River
“The municipality is committed to continuing and improving its efforts to protect the Richelieu River. It has been confirmed that the water in the basin meets Canadian standards for swimming, which is safe for our many users and more than interesting for the possibilities to be developed in the future,” explains the mayor of Chambly, Ms. Alexandra Labbé.
“The Richelieu River is ideal for swimming and all kinds of water activities. The opening of swimming areas and the growth of activities such as paddleboarding, canoeing and kayaking will lead us to design models for sustainable cohabitation between these different activities,” says the general director of Fondation Rivières, Mr. André Bélanger.
There is currently only one public beach intended for swimming on the Richelieu River, located in Saint-Paul-de-l’Île-aux-Noix.
Methodology
The Rivières Foundation, supported by the Gervais-Désourdy Nautical Center team during the first phase in 2022 and by the environment division team for the second phase in 2023, took samples at two regular monitoring sites (Gervais-Désourdy Nautical Center and municipal wharf) between June 14 and August 24, 2023. The Rivières Foundation also conducted screening tours at 29 sites around the Chambly basin, between June 28 and September 10, 2022 during the first study. The analysis was based on the count of Escherichia coli (E. coli).
About the Rivers Foundation
For 20 years, the Fondation Rivières has worked to preserve, restore and enhance the natural character of rivers and contributes to ensuring water quality and access to water for the Quebec population, taking into account social, environmental and economic dimensions. It has conducted studies on bacteriological quality for various municipalities, including Mercier, Repentigny and Saint-Jérôme.
Press release from the City of Chambly
