Branche Castonguay is a River located in Saint-Gabriel-de-Rimouski; La Mitis, Quebec.

• Latitude: 48° 23' 16'' North   (decimal: 48.3878191)
• Longitude: 68° 9' 12'' West   (decimal: -68.1533486)
• Topography Feature Category: River
• Geographical Feature: Cours d'eau agricole
• Canadian Province/Territory: Quebec
• Location: Saint-Gabriel-de-Rimouski; La Mitis
• Atlas of Canada Locator Map: Branche Castonguay
• GPS Coordinate Locator Map: Branche Castonguay Lat/Long