The Otter vessel surveys what’s under the water near an OPG hydroelectric facility. Ontario Power Generation (OPG) is introducing new technology to improve underwater surveys at its hydroelectric facilities. The data helps OPG predict water flows, assess dam capacity during extreme weather events, and support dam safety. Using a sonar system, the Otter can perform high-resolution hydrographic surveys to produce rapid and precise mapping of underwater features. OPG workers with the Otter uncrewed surface vessel.