Dakota County – Lake Byllesby Dam
Boldt was tasked with upgrading the century-old powerhouse that sits on the end of a 3.5-mile long, 1,432-acre lake. The primary project goal was to preserve and upgrade the clean energy generation capability for at least another 50 years.
Project site improvements included replacing the 20- to 40-year old stop logs and interior ventilation system, replacing electrical switchgear; upgrading the powerhouse by replacing the century-old original head gates, draft tubes and overhead crane rails; and installing two new double-regulated, 2.25 MW Z-Turbines (Saxo-Type) and generators. The upgraded generating units double the output, are more efficient and match site head and flow conditions.
Ayres Associates used 3-D scans of the site with BIM programs. These plans helped set the foundations that would eventually hold the turbines. Specialty equipment also was needed to set two, 121,000-pound generators that will supply power to the surrounding area.
Dakota County
Cannon Falls, Minnesota
Ayres Associates / Stantec
General Contractor
Renovation / Equipment Installation
MARKET
Renewable Energy
Project Highlights
- Preserve and upgrade the clean energy generation capability of a 100-year old Ambursen buttress dam and powerhouse. For at least another 50 years.
- Approximately 7,600 cubic yards of CIP concrete, 400 tons of rebar and 180 tons of structural steel.
- Project is a Chase Level 3 Project with a partnership between the contractors, AGC and MN OSHA.
- Boldt replaced the existing powerhouse and turbines, penstock and other associated equipment. Original construction was in 1910.
