Skanska USA Building has completed the major construction phases of the $105 million Cordilleras Behavioral Health Facility replacement project in Redwood City, Calif., with only a handful of subcontractors remaining on-site to complete final punch-list work.
The project, delivered using a construction manager-at-risk approach, began construction in November 2020 for San Mateo County. Skanska joined the effort in 2018 after the county spent nearly a decade planning the replacement of its aging behavioral health campus.
The new 100,000-sq.-ft. campus occupies 7 acres in a valley surrounded by open space and trails. Designed by CannonDesign, it features four single-story mental health recovery centers with capacity for 16 clients each and a three-story co-housing building accommodating 57 residents. Outdoor amenities include recreation areas, open-air gathering spaces and a community garden.
The campus was designed as what is expected to be the nation's first and largest net-zero energy behavioral health facility. RHAA Landscape Architects served as landscape architect, while KPFF provided civil and structural engineering, including retaining walls as high as 20 ft. and foundations for a 300,000-gal. hillside water tank.
The project replaces a 77,000-sq.-ft. facility built in 1952 as a tuberculosis hospital before being converted into a behavioral health center in 1978.
Major site improvements included extensive grading, utility relocations, stormwater infrastructure, roadway upgrades and enhanced fire access. Crews also buried a north tributary, realigned the existing 30-in. Cordilleras Creek storm drain culvert, relocated domestic and fire water mains and extended water and sewer service throughout the campus.
Sustainability features include rooftop photovoltaic arrays, solar-covered parking, natural ventilation in common areas and an air-to-water heat recovery system. The project is targeting LEED Gold certification after originally being designed to achieve LEED Silver.
According to Lindsay Corotis, vice president and account manager of Skanska California, the heat recovery system preheats domestic hot water while allowing residents to independently control temperatures in their living spaces.
The four recovery centers are wood-frame buildings supported on mat foundations, while the co-housing building consists of two stories of wood framing over a concrete podium supported by drilled piers. Dusty Robotics layout technology was used to automate building layout and improve construction efficiency.
Challenging Site
Skanska USA photo
Earthwork proved to be one of the project's greatest challenges because the campus sits within a narrow V-shaped valley bordered by steep hillsides.
"The owner added a trench drain to solve some water issues," Brian Stevenson, senior project manager of Skanska California, told Construction Equipment Guide. "We also had to modify standard drain inlets to work in ADA parking stalls."
Crews constructed soil nail retaining walls reaching 60 ft. in height while reshaping the site to create building pads.
"The existing building was placed in a small flat spot at the bottom of converging ravines," he said. "We carved out the hills surrounding the old hospital to make space for the four smaller buildings and realigned Edmonds Road to make space for the new main co-housing building.
"We cut down the hills on the high side of the site and used the soil to build up the low end to create a flatter site. Between partially leveling the site and backfilling the excavation left after the old hospital was demolished, we moved a lot of soil."
The project also required construction of a 300,000-gal. water storage tank because the municipal water system could not provide sufficient fire protection pressure. Access to the steep hillside tank site was limited to a single dirt road, complicating equipment mobilization.
Unexpected Utilities
Skanska USA photo
Previously undocumented underground utilities created significant challenges early in construction.
"CalWater owned a high-pressure water line running up Edmonds Road," Stevenson said. "The design team was unaware of the 1,100 psi line. Its discovery was a significant problem. The new design called for utilities to cross the high-pressure line several times and digging near an aging high-pressure water line presented an unacceptable safety risk. We had to go back to the drawing board and reroute those utilities to minimize the risk to the builders and future occupants.
"The hospital was built in the 1950s, and there may have been structures prior to that. We encountered quite a few pipes and conduits during excavation activities. Each discovery required us to stop work and investigate to determine if the utility was still active and in use. Fortunately, almost all of them were inactive for some time, and we relocated the few active ones."
Because the existing hospital remained operational just 15 ft. from the new co-housing building, most construction activities were limited to daytime hours. Skanska also developed prefabricated sound-insulating window panels for occupied patient rooms to reduce construction noise while maintaining a therapeutic environment.
Demolition and Construction
Skanska USA photo
The original four-story concrete hospital, including its basement, was demolished between March and June 2025.
Initial work included tree removal, grubbing and temporary road construction to access soil nail wall locations. Earthmoving operations relied on Caterpillar excavators, dozers, loaders, compactors and rollers.
"The majority of the concrete building was pulled down with a large Cat 336 excavator and a Volvo EC480 high reach was mobilized to tear down the elevator tower," Stevenson said.
Additional excavators demolished the basement slab while a Metso crusher processed concrete for reuse as structural backfill, minimizing imported and exported material.
"We waited for the construction of what we called the courtyard, where the old building used to be, and raised it up to grade," said Stevenson, "so there was very little import and export for the project."
Although the site encompassed 7 acres, elevation changes restricted available work areas.
"We had space to maneuver, and it was also tight in the sense that we had to deal with relatively small sections because of the grade changes," Stevenson said. "We had to do work here and there and move crews and equipment. It was a seven-acre site, but we never had 7 acres to worth at the same time."
Evans Brothers Inc. handled earthwork and demolition.
Foundation work began in April 2021. The recovery centers were constructed on slab-on-grade foundations, while the co-housing building utilized cast-in-place piers supporting a concrete podium. Construction sequencing enabled multiple buildings to be framed simultaneously while crews installed mechanical, electrical and plumbing systems.
PVC membrane roofing was installed across the campus. Forklifts supplied materials to the smaller buildings, while a hydraulic crane erected prefabricated roof panels on the co-housing structure.
"It took a week to set and pack the panels together," Stevenson said. "Then they did a full anchoring and placing of the attachments."
The finished campus includes a two-lane asphalt roadway and four parking areas providing 103 spaces.
"The hospital was in the center, and we carved out the hill," said Stevenson. "We built the road around the property and, because we raised the lower side end of Edmonds Road, we raised the grade at the end and had to build back 100 to 300 yards to fix the slope on the road going back."
Constructing the elevated water tank required transporting heavy equipment up the steep access road.
"The pump house pumps the water to the water tanks at the top of the steep hill," Stevenson said. "Taking a 12,000-pound Gradall up and down that hill was tough. Other than that, it was just a lot of moving earth around. One of the interesting things about the high-pressure line was that it was close to the grade. We applied a concrete gravel to bridge it and then we poured to bridge it and then we poured the asphalt over the concrete bridge."
Project Team
Skanska's field management team included Assistant Superintendent Johanna Godoy, Superintendent Don Petersen, Assistant Superintendent Jorge Mora, Laborer Foreman Mario Mora and Superintendents Mike Rashe and Shawn Cervany.
Major subcontractors included Berkeley Cement, Best Contracting, Bradley Concrete, Broadway Mech, Cal Drywall, Collins, Drill Tech, Evans Brothers, Harris, Kwan Wo, Preston Pipeline, Thompson Builders and USGA.
Skanska rented equipment from United Rentals, Herc Rentals and Cresco Equipment Rentals.
"We don't rent a lot of big equipment," Stevenson said. "A lot of what we rent are smaller things like air scrubbers and dehumidifiers, and the dealerships were very good, very responsive on this project. When we needed equipment, they were there right away."
