Subject: Water Level Update

Warmer temperatures early last week as well as rain, including a large downpour early in the morning of April 11th, had a significant impact on water levels throughout Northeastern Ontario.

In the last two weeks alone, water levels are up 86 cm at Rabbit Lake, 49 cm at Lady Evelyn Lake, 125 cm at Frederickhouse Lake, 79 cm at Horwood Lake, 45 cm at Mesomikenda Lake and 121 cm at Mattagami Lake. Please note that all reservoirs fill at different rates, so comparing increases from one reservoir to another isn't a valid comparison.

Recent cooling temperatures last weekend slowed inflows into reservoirs as the snowpack stopped melting and rain turned to snow. As of April 15th, the snowpack was holding anywhere from 56mm to 99mm of water on the Abitibi River system (Frederickhouse Lake Dam), 33mm to 69mm of water on the Mattagami River system (Horwood, Mesomikenda and Mattagami Lake Dam) and 28 to 61mm of water on the Montreal and Matabitchuan River systems (Rabbit and Lady Evelyn Lake Dam).

Reservoirs are approximately a quarter of the way filled right now, which is about normal for this time of year. There is still another month to go before reservoirs are required to fill. Wet weather is in the forecast for parts of the next week, along with warmer temperatures, which means inflows should start to pick up again over Easter weekend as rain and snowpack drain into their respective river systems.

Information on water levels should be updated later today on the OPG Web site. Visit for more information. Click on one of four river systems in Northeastern Ontario (Abitibi, Mattagami, Matabitchuan or Montreal) and select the appropriate dam for the latest information on flows and water elevations.

If you're out at the cottage or near the water this long weekend, remember to Stay Clear, Stay Safe!

Marcel Pelchat
Public Affairs Officer
Ontario Power Generation