Lac Martineau is a Lake located in Lac-Walker; Sept-Rivières, Quebec.

• Latitude: 50° 45' 45'' North   (decimal: 50.7625)
• Longitude: 67° 23' 37'' West   (decimal: -67.3936111)
• Topography Feature Category: Lake
• Geographical Feature: Lac
• Canadian Province/Territory: Quebec
• Location: Lac-Walker; Sept-Rivières
• Atlas of Canada Locator Map: Lac Martineau
• GPS Coordinate Locator Map: Lac Martineau Lat/Long