City tackles Lac des Nations water quality issue
Taking note of the quality of water in Lac des Nations portrayed in a recent assessment, Sherbrooke municipal council has begun an initiative gathering several key stakeholders to look for a solution. In 2016, the water quality in the lake was rated ‘D’ more than 60 per cent of the time.
Council agreed to maintain the summer monitoring program, including a suspension of nautical activities in Lac des Nations, based on the results of bacteriological analyses and the preventive closure of Lucien-blanchard beach. Improvements will be made to take account of the knowledge gained in 2016.
Suspending activities is aimed at preventing the exposure of water skiers to a frequently high levels of bacteriological contamination in the lake’s waters. This practice was introduced last summer, in partnership with the DSP and the MDDELCC.
In 2016, water skiing was suspended 12 times due to a D rating, mostly during dry weather. Water skiing is part of the primary contact activities along with swimming and a D rating results in the suspension both.
The analysis showed that the western part of the lake (near the Armandnadeau Pavilion) is more contaminated than the eastern sector (near the Marché de la Gare). For example, a D-score was obtained for 21 of the 37 days sampled last summer, but it was possible to maintain water skiing activities on some days using a route, avoiding a more contaminated area.
The results obtained in dry weather in the river upstream from the lake indicate the presence of a wastewater discharge somewhere between the Lucien-blanchard beach and the entrance to Lac des Nations and an action plan has been submitted to undertake and prioritize field research in order to locate sources of contamination and to correct the situation. At the same time, the DSP will continue collecting data to assess the degree of exposure to members of the water ski school.
Despite the fact that regular sampling and the suspension of the activities of the Jean-perrault school have financial and organizational implications, this whole approach remains positive. It aims to provide quality water to ensure long-term activities on the Magog River and Lac des Nations and knowledge acquired in Sherbrooke could also help other municipalities that offer water skiing activities in urban areas.