Report on the Lake Mats Project
In 2023, the directors of the Environmental Fund’s Board of Directors launched a pilot project to protect our lake from the spread of potentially invasive aquatic species. The members of the Fund’s Board of Directors all voted and agreed to go ahead.
Project title
“Pilot project to protect our lake from invasive plant species”.
Project leader
Board of Directors of the Fonds environnemental du Lac St-François-Xavier.
General project summary
The project involved the manufacture of a lake mat made from geotextile material to be used as a tool to control the spread of invasive aquatic plants. Lake mats have been tried and tested by many lakes and sold by many companies as an effective and environmentally friendly method used to control the spread of invasive or dense aquatic plants. They work simply by blocking sunlight, thus preventing the growth of aquatic plants. They also do not stir up sediment, but rather compress it.
The aim of this project is to determine whether the lake community is capable of manufacturing, installing and removing lake mats.
You can certainly buy a ready-made lake mat, but if we have to buy several mats, then the total cost of lake mats becomes quite high. Cost is only one of the main factors that make us want to make it ourselves. The other factors were size, type of mat and installation method. Mats are available in many different materials, so we had to choose one that was environmentally friendly and easy to handle. Next, we had to determine the manufacturing method and the size of the mat. Size was crucial, as we had to take into account the fact that we needed to be able to physically install and remove it ourselves, while still being large enough to actually function. Finally, the method of installation and removal was also analyzed at different locations and depths of the lake. Read more…
On the main road north of the bridge at Montfort, winter maintenance of the long shoreline requires large quantities of sand and de-icing agent to ensure safe traffic flow. This sediment eventually sinks, mainly in spring, and ends up in the lake. Residents who have lived in Montfort since their youth remember when it was possible to dive from the bridge. The water was at least 6 feet deep. Last summer, in 2023, the depth was around 16 inches. The accumulation of sediment is constant from year to year.
To remedy the situation, the Ministry of Transport (MTQ) installed a sand trap in 2013. Two collectors, one on each side of the road, channel some of the sand and sediment into the trap along with water from snowmelt and rain. The purpose of the trap is to retain the sand and sediment and allow the water to flow into the lake via a large pipe. Unfortunately, the trap isn’t enough to hold back everything. When it rains heavily or when there’s a thunderstorm, we sometimes see large banks of sand and sediment being dumped into the lake through the pipe. The sand trap should be emptied more often. Read more…