Lac Once is a Lake located in Cascades-Malignes; La Vallée-de-la-Gatineau, Quebec and has an elevation of 294 meters.

• Latitude: 46° 48' 45'' North   (decimal: 46.8125)
• Longitude: 76° 3' 54'' West   (decimal: -76.065)
• Topography Feature Category: Lake
• Geographical Feature: Lac
• Canadian Province/Territory: Quebec
• Elevation: 294 meters
• Location: Cascades-Malignes; La Vallée-de-la-Gatineau
• Atlas of Canada Locator Map: Lac Once
• GPS Coordinate Locator Map: Lac Once Lat/Long