Lac Dumortier is a Lake located in Lac-Nilgaut; Pontiac, Quebec and has an elevation of 309 meters.

• Latitude: 46° 28' 9'' North   (decimal: 46.4692270)
• Longitude: 77° 42' 31'' West   (decimal: -77.7086387)
• Topography Feature Category: Lake
• Geographical Feature: Lac
• Canadian Province/Territory: Quebec
• Elevation: 309 meters
• Location: Lac-Nilgaut; Pontiac
• Atlas of Canada Locator Map: Lac Dumortier
• GPS Coordinate Locator Map: Lac Dumortier Lat/Long