Lake Minnewanka 1912 Dam
3D photogrammetric model of a flooded hydroelectric dam in Lake Minnewanka, Alberta, Canada.
This project documents the creation of a 3D photogrammetric model of the 1912 Lake Minnewanka dam, a fully submerged hydroelectric structure in Banff National Park. Lake Minnewanka has been dammed three times: first in 1895 to raise water levels for recreation, again in 1912 for hydroelectric storage, and finally in 1941 under the War Measures Act. Each new dam flooded the previous one, leaving the 1912 structure preserved underwater and now a well-known (but challenging) dive site.
The model was created primarily for local divers. Visibility at the site is rarely good enough to see the entire dam in a single dive, making it hard to understand its full scale and layout. A 3D model allows divers to contextualize what they experience underwater and explore the site in a way that would otherwise be impossible without exceptional conditions.
Data capture was the most challenging part of the project. Lake Minnewanka has poor summer visibility, so imaging had to be done in winter after suspended sediment settled out. Water temperatures were below 2 °C, and the site reaches depths of roughly 28 m, making long scuba dives impractical. Instead, imagery was collected using a consumer-grade CHASING Gladius ROV modified with mounted GoPro cameras and dive lights. Accessing the site required coordinating with ice divers and cutting a hole through the frozen lake surface, turning what might normally be a desk-based workflow into a full field expedition.
Thousands of video frames were extracted and processed in 3DF Zephyr to generate the initial photogrammetric reconstruction, then cleaned, repaired, and rendered in Blender. These tools were new to me at the start of the project, and the workflow required persistence, experimentation, and iteration to succeed. While the final model has limitations, it exceeded my expectations and demonstrated how accessible tools—combined creatively and used under challenging conditions—can document complex underwater heritage sites.
This project highlights both the potential of underwater photogrammetry and the value of persistence when working far outside ideal conditions. It also reflects my interest in using spatial and 3D techniques to make inaccessible places understandable, whether for local communities, technical audiences, or anyone curious about what lies beneath the surface.
2024-04-21