Blackhawk down

Construction of the first iteration of the Blackhawk Generating Station in Beloit, Wisconsin, was completed in 1907. The steam-powered, coal-fired power plant, which was renovated in seven stages throughout the first half of the 20th century, remained in operation until 2005. In 2010, plant owner Alliant Energy made the decision to decommission the facility due to a reduction in demand for power within the plant’s service territory.

While the decommissioning of a power plant normally marks its final chapter, the structure’s location and durable build got the attention of administrators at neighboring Beloit College, who identified its potential as a fitness and recreation space for students.

“The college has had an immediate need for new recreation, fitness and health space, and a longer-term need for new student union space,” Daniel Schooff, Beloit College’s chief of staff and secretary of the college, told Civil Engineering, the magazine of the American Society of Civil Engineers, in 2015. “The college hired local engineering and architecture firms to examine the structure, look at the original blueprints and consider the feasibility of repurposing the facility to meet the campus’s needs. What we found is an incredibly robust structure. It is an all-steel-frame structure. In the engineering of buildings [in the early 20th century], you were typically overbuilding. The functions that the college hoped to build would place much less load on the structure than what it already supported.”

Before the work could commence, NADC was asked to provide engineering plans to protect architectural items throughout the powerhouse that needed to remain protected during the demolition phase of construction. Because the college wanted to preserve the industrial look and feel of the building, structures like Blackhawk’s coal hoppers, overhead cranes and 175-foot smokestack, among other structures, were to remain.

According to Vic Chappel, sales and marketing for NADC, the Blackhawk project required nuanced planning and coordination between parties to ensure the structure retained its integrity throughout the demolition process.

“North American Dismantling Corp. was proud and excited to be a part of the powerhouse to student center conversion project, as it allowed us to interject our decades-long experience and capabilities involving interior and selective demolition,” he says. “In planning this project, NADC coordinated with Alliant Energy and Beloit College to help ensure the project was completed safety, timely and on budget. NADC handled all permitting associated with the project including demolition and abatement permits, road closures, river work permits [for the nearby Rock River] and more. NADC also coordinated with Beloit College to create a final topographical survey which allowed for proper site drainage while leaving a suitable area for Beloit College to also build a new addition. NADC [was also charged with] executing the salvage of many items which were plotted to remain in place for historical value as planned by Beloit College.”

The project at hand

Before NADC could get to work removing structures and demoing parts of the building, the company subcontracted Environmental Demolition Inc. to perform abatement on the project. Although NADC says the majority of the abatement had been previously performed by another contractor, Environmental Demolition Inc.’s work consisted of the removal and disposal of electrical components, pipe insulation, window glazing and other friable and non-friable asbestos, and other retired plant components.

After the abatement was completed, NADC began removing all components that weren’t slated to remain, including two boilers, two turbines, circulating water piping and other retired operational components. NADC also removed two precipitators from the front of the building as part of the demolition scope of work. Chappel says the main scope of demolition activity consisted of coal handling outbuilding work, exterior structure and foundation demolition to 2 feet below grade, decommissioning of site mechanical systems, removal and disposal of all remaining oils and gases, decommissioning of discharge piping and screenhouse and intake tunnels, and removal and disposal of all universal waste.

NADC says it also contracted the removal of a seawall from the adjacent Rock River and the closure of water intakes and discharges. The building shell and all structural steel was left in place.

Between the need to preserve certain components, the age of the site and space constraints, Chappel says there were a number of obstacles that NADC had to overcome on the job.

“The way the structure was built and NADC’s specific scope of work was a challenge in itself,” he says. “NADC developed a complex work plan that varied from means and methods used on other projects. Between the construction style of the boilers; the salvage-in-place nature of many components that forced NADC to take extra precaution in execution of the work to be able to protect and save these items; and the limited egress available for concrete, garbage and scrap, NADC had to develop a well-thought-out demolition process. We were able to plan and execute with the help of all team members to create a successful demolition project.”

According to Chappel, demolition took the crew of 30 approximately seven months to complete, with the project ranging from June 2017 to January 2018. In all, 35,000 total manhours were performed without incident on the job.

The demolition produced ferrous and nonferrous metal, C&D waste and concrete. All steel from the project was recycled at a local steel recycling center, all concrete was recycled at a local concrete crushing facility and the C&D waste was sent to the local landfill.

Through NADC’s diligence on the project, the company was able to recycle 95 percent of materials derived from the Blackhawk demolition.

“NADC makes every effort to recycle all materials feasible on every project,” Chappel says. “NADC takes care to sort and prepare materials to the best of our ability so as to limit both disposal costs and environmental impact.”

A new beginning

The Powerhouse, as it’s known on campus, was officially opened in February.

The new building includes meeting rooms, gathering spaces, an indoor track, a lecture hall and theater, a pool, a café, fieldhouse, a conference center, multiple fitness spaces, outdoor decks overlooking the Rock River and a Riverwalk.

About the project, Beloit’s website states, “A glorious 21st century use for a quintessentially 20th century facility, the building provides a spectacular space for the community to come together to work, train, eat and play. It is a showcase of sustainable design and is housed in one of the state’s most important historic buildings, tying the college and the city of Beloit closer to the Rock River.”

“From the very outset, this has been both a project that was going to be enormously valuable to the college community and the city of Beloit,” Beloit College President Scott Bierman told the Wisconsin State Journal. “This project, at its core, is fundamentally a student center, and for those reasons, we expect that prospective students and their families will pay close attention to a college that has devoted this much energy and resources to improving the quality of their experience.”

With a history dating back over 100 years, the repurposing of the Blackhawk Generating Station serves as a standing monument linking the city’s past to those tasked with creating its future.

“It’s a symbol,” Schooff told the Wisconsin State Journal. “It’s an echo of our industrial heritage.”

The author is the editor of Construction & Demolition Recycling magazine and can be reached at aredling@gie.net.