The Beauharnois generating station, operated by Hydro-Québec, is located along the St. Lawrence Seaway. The station comprises 36 turbines capable of generating up to 1,903 MW of electrical power.
After several years of eel migration monitoring by AECOM, the first eel ladder was built in 2002, on the west side of the dam, and a second on the east side in 2004. Every year, tens of thousands of eels use the ladders to cross the dam and continue their migration.
AECOM is responsible for the operation and maintenance of various aspects of the facility, including:
- Daily remote monitoring of eel passages
- Weekly verifications of the pumps and operation of the eel ladder components
- Weekly testing of the monitoring devices
- Operations reporting at the end of the season
Since AECOM designed and fabricated many of the eel ladder components and participated in their installation, operation and maintenance, our understanding of the many parts of this system is exhaustive, and troubleshooting can be done quickly and easily.
Monitoring of the eels transiting through the facility is done with the following:
- Eel counters
- Passive Integrated Transponder (PIT) tag detection systems
- Length and weight measurements of captured eels
- Water level and temperature loggers
Designed and fabricated by AECOM, the photoelectric eel counters installed at the Beauharnois eel ladders have provided reliable estimates of the number of eels that transit the facility during the season.
Every year since 2011, AECOM has been PIT tagging 400 eels caught at the West ladder, then releasing them into the Ottawa River. The detection of these tagged eels at other study sites provides valuable information on the behavior of the American eel.

