Lac Grandmesnil is a Lake located in Lac-Walker; Sept-Rivières, Quebec and has an elevation of 445 meters.

• Latitude: 51° 18' 30'' North   (decimal: 51.3083696)
• Longitude: 67° 33' 16'' West   (decimal: -67.5544302)
• Topography Feature Category: Lake
• Geographical Feature: Lac
• Canadian Province/Territory: Quebec
• Elevation: 445 meters
• Location: Lac-Walker; Sept-Rivières
• Atlas of Canada Locator Map: Lac Grandmesnil
• GPS Coordinate Locator Map: Lac Grandmesnil Lat/Long