Mille Roche Power House
The creation of the St-Lawrence seaway in 1958 resulted in an increase in depth, allowing larger ships to access the Great Lakes. As a consequence, numerous villages, roadways, locks, power houses, and canals were submerged and are now popular dive sites. One such site is located near the former Maple Grove in Cornwall, Eastern Ontario, Canada. Divers can explore the remnants of the Mille Roches Power House, which offers a maximum depth of 17m and visibility of approximately 4m. This dive site is suitable for beginners. For more information and a detailed description of the site, please visit the diving guide provided by the official website of Save Ontario Shipwrecks.
Diving Conditions Score for Mille Roche Power House
6.3
Above AverageDecent conditions, proceed with caution.
The score is based on a calculation of the current weather and sea conditions.
Dive Site Overview for Mille Roche Power House
Depth
17m
Visibility
4m
Experience Level
beginner
Weather Conditions for Mille Roche Power House
Wave Height
1m
Wind Speed
10.3 m/s
Water Temp
18°C
Visibility
35.2km
Cloud Cover
0%
Wave Period
8s
Air Temperature
22.4°C
Precipitation
0 mm
Detailed 7-Day Diving Forecast for Mille Roche Power House
Alpha
Dive Score Chart for Mille Roche Power House
Best time to dive: 6:00 with score 7.893333333333333/10. Water conditions: Waves 1m, Wind 3 m/s.Best night dive time: 5:00 with score 7.223333333333333/10.
Chart showing hourly dive conditions including wave height, wind speed, water temperature, and visibility throughout the day.
Sunrise at Mille Roche Power House: 06:00
Sunset at Mille Roche Power House: 18:00
Optimal diving conditions at Mille Roche Power House are affected by daylight hours. Sunrise occurs at 06:00 and sunset at 18:00, which impacts visibility and water temperature for scuba diving and snorkeling.
Best Overall
6:00Score: 7.9/10
Waves: 1m (8s), Wind: 3 m/s
Best Night
5:00Score: 7.2/10
Waves: 1m, Wind: 4.7 m/s
Seasonal Analysis for Mille Roche Power HouseAlpha
Historical patterns and best seasons for diving at Mille Roche Power House
The dive score combines all factors to rate overall diving conditions throughout the year. Higher scores indicate better diving conditions.
Monthly Dive Score Analysis - Seasonal Diving Conditions
Higher values indicate better diving conditions
Seasonal DiveScore Chart
This chart displays monthly diveScore data throughout the year, showing seasonal patterns. The data is presented as a bar chart with an overlaid line graph.Dive scores range from 1 to 10, with 10 being optimal conditions.
Higher values indicate better diving conditions
Best Season for Mille Roche Power House
Winter
Avg. Score: 9.9/10
Winter offers the best overall diving conditions with calmer seas and better visibility, despite cooler temperatures.
Best Months for Mille Roche Power House
January
Score: 10.0
February
Score: 9.9
December
Score: 9.8
Ideal Conditions for Mille Roche Power House
Water Temp
24.5°C / 76.1°F
June
Visibility
20.1m / 65.9ft
October
Wave Height
0.2m / 0.7ft
January
Wave Period
8.0s
January
Seasonal Insights for Mille Roche Power House
Mille Roche Power House shows typical northern hemisphere patterns with June being the warmest month (24.5°C) and December the coldest (20.5°C). The calmest conditions typically occur in January with average wave heights of 0.2m and wave periods of 8.0s. The most comfortable wave conditions are in January with a low wave steepness ratio, creating gentler swells. January offers the longest wave periods (8.0s), creating more comfortable and predictable conditions for boat entries and exits. Ocean currents are slowest in January (0.5m/s) and strongest in January (0.5m/s). January is usually the driest month with 0.0mm of precipitation. For beginners, the best time to visit would be during January to March, when ocean conditions are calmer with long-period waves and currents are typically weaker. Experienced divers might enjoy the challenges and potentially better visibility during the shoulder seasons, with moderate currents that can improve marine life encounters.
Last updated: 1 min. ago - Jun 22, 2026
Note: This dive site is not a verified dive site. Please dive with caution. This dive site might have incorrect information by the community.
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