UC Davis Health and DPR Construction Top Out 48X Complex

Craft workers in Hi-Viz clothing take a photo of their colleague signing the traditional final beam.
48X craft team members photograph the final beam before installation. Photo: Bill Michie

Amid cheers from a festive crowd, the DPR Construction and SmithGroup design-build team topped out the UC Davis Health 48X Complex, a new four-story, 268,000-sq.-ft. ambulatory surgery center in Sacramento, California.

Since breaking ground in November 2022, craft workers from various trades have worked 86,926 hours on the project. The project team’s dedication and hard work were celebrated with a luncheon, raffle prizes, and the traditional signing and placing of the last structural beam.

“We’re proud of our team out here at 48X. They have persevered through unprecedented rainfall and our typical hot summer,” said Abe Sipes, DPR Construction’s project executive leading the job. “Their hard work and team approach have put the project in a great position at this point in the schedule.”

California Erectors, the steel erection contractor on the project, used over 4,010 steel members to build the steel structure. “We’re here right now because of the incredible work of California Erectors and their ironworkers,” remarked Sipes.

The placement of the final steel beam brings the new ambulatory surgery center one step closer to serving the greater Sacramento community.

Ironworkers standing at the top of a steel structure while a beam is flown into place by crane.
Ironworkers preparing to receive and place the final steel beam. Photo: Bill Michie
By the Numbers

Pounds of Steel Shipped from Idaho


Shop Fabrication Welds


Bolts Sent to Project


Square Feet of Metal Decking


Cubic Yards of Concrete Poured to Date


Miles of Wide Flange Beam and Column Material


California’s capital has seen dramatic population growth over the past decade, driven by new opportunities and relative affordability compared to other California cities. This growth has increased the demand for healthcare services and facilities in the Sacramento area. 48X is a key piece of UC Davis Health’s strategy to serve the community and help address the ambulatory operating room capacity shortage at the University’s main hospital.

“The future of healthcare is fundamentally evolving, and this facility will help us provide innovative treatment and care to our growing community,” said Creed Kampa, Director of Strategic Programs for UC Davis Health. "We are thankful to the entire DPR and SmithGroup design-build team for all their accomplishments so far in bringing this building to life.”

A rendering showing the new two-story building from the corner.
The new ambulatory surgery center, to be located at the corner of the newly remodeled intersection of 48th and X streets will be called the “48X Complex,” reflecting its location at the corner of 48th and X Streets in Sacramento. Rendering: SmithGroup
The future of healthcare is fundamentally evolving, and this facility will help us provide innovative treatment and care to our growing community.

Creed Kampa

UC Davis Health

Designed by SmithGroup, the new facility will be one of the most technically advanced ambulatory surgery centers in the United States. It will support a preliminary program of 14 operating rooms, 59 pre- and post-operative recovery bays, 14 single-occupant 23-hour recovery rooms, 96 clinical exam rooms, and 19 clinical treatment rooms.

"The new Ambulatory Surgery Center, 48X Complex, is a 'destination' within the UC Davis Health medical campus. The design emphasizes pedestrian accessibility through a central breezeway and incorporates natural light and views of the outdoor landscape,” said Aimee Chan, Lead Designer with SmithGroup. “It also connects to other campus resources, as well as the surrounding community, while catering to visitor needs. This approach aligns with biophilic design principles that enhance people's physical and mental health well-being.”

The building will include public spaces, clinical support, operations space, sterilization, pharmacy, imaging space, physical therapy space, and administration support space to facilitate patient support and education.


The project team understands the demand for this facility and the benefit it will provide the community. They are dedicated to maintaining the project’s schedule but faced challenges early when they, like many projects in California, were impacted by the tremendous winter rainfall.

The project began excavation mere weeks into the extended rainy period and was at risk of turning into a mud pit. This could create significant delays that would impact all aspects of the project. At the recommendation of DPR’s SPW Concrete team, the project team elected to invest in placing a “mud slab” at the bottom of the excavation.

A concrete working surface with various materials staged for construction. A neighboring building overlooks the jobsite.
The “mud slab” at 48X helped prevent the site from becoming a mud pit and provided DPR’s SPW teams with a safer and more efficient work environment. Photo: Mike MacBean

A mud slab is a thin layer of non-structural concrete placed overtop a dirt floor used to create a flat, solid working surface. At 48X, the mud slab is roughly 3 inches thick and covers the 80,000-sq.-ft pad of the new building. It was poured in one day, and SPW crews were able to start working on it within 48 hours.

“Choosing SPW Concrete to execute the structural concrete work allowed us to come in early in a design-assist fashion to help design schedule and cost efficiencies for UC Davis Health,” said Mike MacBean, DPR’s Concrete Lead on 48X. “These efficiencies have helped us stay on schedule given the amount of rain we received. We have achieved substantial productivity increases from a quality standpoint by being able to work off this mud slab.”

The flat surface also allowed the team to save significant time using Dusty Robotics’ technology to complete the building layout. This is the first time the robot has been used for foundations at DPR which was completed in just two days. The team’s creativity, innovation, and investment paid off and prevented the project from losing a single day on the schedule due to rain.

The project is anticipated to be operational in 2025.

We think you'll like this, too.