The existing turbines inside the dam are more than 100 years old. They have had several major overhauls, and need to be replaced.
Combined with an aging powerhouse structure, it has been determined that an upgrade will be required. Dakota County completed designs and are moving forward to replace the turbines and upgrade the powerhouse.
In 2017, the state legislature allocated $6 million in bonding to complete a turbine upgrade project at the Byllesby Dam.
Dakota County selected and contracted with Voith Hydro to design, fabricate and furnish the turbine equipment. Boldt Construction was selected to provide installation and construction services for the project. Ayres Associates and Hatch are providing engineering and design related services for the project.
See time lapse pictures of project progress
Project goals
- Preserve the clean energy generation capability for at least another 50 years.
- Replace century-old original head gates, draft tubes, overhead crane rails, generators and turbines.
- Remove flood damaged concrete and bedrock chunks from river channel.
- Address dam safety issues like cracks in the Ambursen buttress dam (3) and a stormwater pipe penetration through the north embankment.
- Restore the historic character of the façade by replacing blocked-up windows and repairing walls and roofs.
- Replace the 20- to 40-year old stop logs, interior ventilation system and electrical switchgear.
- Upgrade to generating units that are more efficient and are matched to site head and flow conditions.
- Address worker safety concerns by relocating the maintenance and operator entrance out of the icy spray zone.
Dakota County began construction in October 2020 with completion in summer 2023.
Please refer to the
Lake Byllesby Dam Projects page for more information on proposals, bidding and potential contracts with Dakota County to complete this project.