Our mission and goals

Protect the environment of Trois Montagnes lake, including the following specific objectives:

  • Protect its shores and surroundings, including its draining basins, against any change that could harm its environment;
  • Proceed with an annual fish stocking;
  • Protect and defend the interest of the lakefront owners regarding specifically the protection of the environment.

A little history

The association was founded in 1979 and since that day, a dedicated team of pioneers and visionary volunteers have contributed to its growth. Several issues are prioritized, including access to the lake, fish stocking and monitoring of water quality.

There are over 295 waterfront homes belonging to 280 owners, of which 161 are members of APEL. The more we are, the better we can defend and protect our environment.

Fauna and flora

Since 1939, fishes are stocked in our lake. In May 2015, 1,500 rainbow trouts were put into the lake to improve its fisheries health.

Overall, 30% of APEL revenues are allocated to fish stocking.

We remind you that a Lake Trout under 55 cm (22 in.) must be returned to the water and we invite the fishermen of the lake to inform us about their summer catches. Just send us a message at our email address This e-mail address is being protected from spambots. You need JavaScript enabled to view it .

Sport fishing in Québec (Zone 10 regulation)



Catch limit


April 23, 2015 to September 13, 2015


Maximum of 10

Lake Atlantic Salmon (Ouananiche)

Maximum of 3

Lake Trout (touladi) and Splake

Maximum of 2

55 cm and longer

Rainbow Trout

Maximum of 20

Cutthroat and Brown Trout

Maximum of 5

Water Quality

Water quality tests conducted in the context of the RSVL during Summer 2014 indicated good results compared to those of 2013. The average transparency, measured with the Secchi disk in the deepest part of the lake, was 7.2 meters, indicating very clear water. In addition, for the third year in a row, water samples for measuring phosphorus (nutritional element), the concentration of chlorophyl (microscopic algae in suspension) and organic carbon produced good results. Our lake is between the ultra-oligotrophic and oligothrophic stages of aging. Transparency tests will continue yearly, but water samples will be taken only every 5 years, in accordance with the RSVL's protocol.

However, we did note that water in shallow areas was less clear than in preceding years. The stirring caused by boats, wind and rain, and an increase in matter of mineral or organic origin in suspension may explain this change. An increase in the erosion of shores could also be a factor. We will therefore pay special attention to changes in the water and shoreline in shallow areas because this could result in premature aging of our lake.

Some 2014 tests, among them for phosphorus, are better than in 2013 (see graphs below). All efforts made by lake residents and the Municipality over the last few years to limit nutrient addition in the lake have greatly contributed to improving water quality and it is crucial that we continue these efforts in order to preserve the natural state of our lake.

For more detail on water quality, you might want to check test results for previous years on the the Ministry of Sustainable Development, Environment and Parks website (