Boldt Construction completes major upgrade to historic Minnesota dam

The Manitowoc MLC300 VPC-MAX, brought in August 2023, was used to install the new generators, each weighing over 121,000 pounds. Photo: Manitowoc

Minnesota, USA-based Boldt Construction, in partnership with Dakota County and Xcel Energy, successfully modernized the 114-year-old Lake Byllesby Dam in Minnesota. Using two Manitowoc crawler cranes—a 2250 owned by Boldt and a rented MLC300 VPC-MAX—the project involved building a new powerhouse and installing two generators, doubling the dam’s capacity to 4.4 megawatts, enough to power 2,400 homes.

The project, which began in 2021, faced challenges with the aging concrete structure and water exposure. Over 1.7 million pounds of concrete were removed to lay the foundation. The Manitowoc 2250, on-site from the start, played a key role in material handling, while the MLC300, brought in August 2023, was essential for lifting the 121,000-pound generators.

“The generators and cranes were positioned near the pump house,” said Aaron Utley, Boldt’s project manager. “Our crews carefully guided them into place while engineers ensured all connections were secure.”

The successful lifts were completed over two days of favorable weather, demonstrating the expertise of Boldt’s operators and the reliability of Manitowoc equipment. Boldt also preserved elements of the original powerhouse, incorporating historical turbine equipment into the nearby park.

This upgrade enhances the dam’s role in the region’s energy infrastructure while preserving its historical significance.