Riverton, Canada offers 4 beaches perfect for sunbathing, surfing, swimming, and more. Riverton, Manitoba, Canada, is known for Hecla-Grindstone Provincial Park. The best time to travel to Riverton, Canada, is during the summer months of June to August, when the average air temperature is around 20°C (68°F) and the water temperature is approximately 15°C (59°F). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!