TriHealth Good Samaritan Western Ridge Medical Center Expansion Overcomes Site Challenges and Electrical Shutdowns
Challenging Terrain: Skanska Builds Cincinnati Hospital Expansion Into Side of Hill While Minimizing Impacts on Active Campus
Cincinnati’s hilly terrain often impacts construction – but rarely to the extent experienced by Skanska USA in building the TriHealth Good Samaritan Western Ridge Medical Center expansion.
“The biggest challenge of the project is the site,” said Jeff Smoker, Vice President – Preconstruction for Skanska’s Cincinnati office, which serves as Construction Manager at Risk. “It looks like we cut out the side of a hill to build a building on it.”
Pushing back the rock slope, along with an unexpected clay seam, complicated construction of the new 92,600-square-foot, three-story building that will tie into the medical center’s existing two-story building. However, after mass excavation and a short problem-solving delay that resulted in a new retaining wall, crews topped out steel in late September to stay on schedule for a fall 2020 completion.
TriHealth awarded the $37 million CM at Risk contract to Skanska in November 2017 after a qualifications and fee-based selection process. “We came on at the start of conceptual design and conducted various cost exercises throughout the rest of the design process to achieve the owner’s goals regarding budget,” said Aaron Sparn, Skanska’s Senior Project Manager.
To finish construction faster, Skanska released bid packages last January for long lead-time items such as steel, precast, curtain wall storefront, and a major electrical relocation. They bid the remainder of the contracts in May and June, then started vertical construction.
When complete, the project will more than double the size of the Good Samaritan Western Ridge campus, expanding primary care as well as specialty care for cancer and heart patients. The original facility, opened in 2010, includes a 24-hour emergency department and laboratory services.
Digging Out a Hill
Crews started excavation in November 2018, then ran into a surprise that delayed their efforts. “It was supposed to be a shale site, but at the top of a large cliff, we found a clay seam,” Sparn explained. “Because of that, we couldn’t slope back tight enough to keep the footprint of the required parking.”
Skanska spent a couple of months working with TriHealth and the engineering firm hired by the owner to determine the best solution. Early this year, “We put in a precast concrete lagging wall to stabilize the top of that slope so we could cut it steep enough,” Sparn said
In addition to the retaining wall, work included many shear rock cuts. Although there was a building pad mostly established before Skanska started, “We had to take the rock cuts further back and dig down deeper,” Smoker said.
After pushing back the slope and rebuilding it with the excavated materials, crews still hauled out 32,000 cubic yards of rock.
Before the project finishes, Skanska will coordinate multiple shutdowns of electrical service to the existing facility. The first shutdown occurred last summer.
“Where the new building ties in, there was a primary transformer that fed the electrical for the existing building,” Sparn said. “We had to coordinate the removal and relocation of that with the local utility company and go through a shutdown process with the owner – first shutting down normal power to move the transformer, then shutting down emergency power to move the generator out of the footprint.”
Because medical offices occupy 75 percent of the existing building, “We phased the shutdown for nights or weekends when those offices weren’t active,” Sparn said. “However, the emergency department in the remaining 25 percent of the building stays open 24/7. Before the shutdown, we met with TriHealth users to work through the impacts and make sure the facility stayed up and running the entire time during the switchover.”
To minimize downtime, Skanska also oversaw the installation of all the new conduits, wiring, and electrical equipment before the shutdown.
Another shutdown will occur later in the project. “There’s a main switchgear in the existing building that we’re tied into now,” Sparn said. “When we get the new building established, we’ll set a new piece of switchgear in the new building, then provide a new feed to the existing building and do another shutdown to tie in all of that.”
As work continues, Skanska will coordinate other special measures to minimize impacts on the active campus. For instance, “There’s a delivery area in the back – and there’s really no other place to receive those – so we’ll put in a temporary scaffold to protect from an overhead standpoint,” Sparn said. “Tying into the existing building will also be a challenge in mitigating vibrations and noise. We’ll need infection control measures in place to ensure that the construction environment is kept separate from the patients visiting the facility every day.”
To avoid conflicts and congestion, construction traffic utilizes a newly built access drive, which will become a permanent access route when the new building opens. Until then, patients are using one entrance instead of two.
“Because the new building will tie into the existing building at the medical offices entrance, we had to shut that entrance down and reroute everyone through the emergency department entrance,” Sparn said. “That involved relocating exit signs to make sure we’re following life safety measures and putting in a temporary turnaround drive for dropping off patients. To help that process, the owner hired an onsite valet to ease the burden on patients.”
When complete, the first floor of the new structure will house cancer services, including a linear accelerator and infusion bays. Primary care services will occupy the second floor, with specialty exam rooms on the third floor.
Some medical services will move from the existing building to the new, then crews will renovate the vacated areas. For instance, cardiology services will expand into the existing primary care area once it moves to the new building. Crews will start the 19,600-square-foot renovations when the new building finishes in fall 2020, with completion of all the work scheduled for spring 2021.