William VanHercke began working on projects at Denver International Airport (DIA) right out of college in 1993, while it was still being built. Thirty-two years later, he’s still there, working on the airport’s $2.1-billion capital improvement program.

“I was finishing my college degree, and I worked as a junior engineer on two runways,” says the vice president at Jacobs for US West aviation. He worked as deputy project manager on the airport’s sixth runway in 2003 and is now a principal engineer for the planned seventh runway and future consolidated car rental facility. “When I first started, we were building out in the middle of nowhere,” he recalls. He has seen the vision for the greenfield airport—to be a major economic engine for the region—come to fruition.

A key milestone of that continually evolving vision was hit on Aug. 5, when the new east security checkpoint in the Jeppeson Terminal’s Great Hall opened. It is in the last of three phases for the revamp of the Great Hall, “the most prominent project in our capital improvement program,” says Phil Washington, CEO of DIA, noting that the terminal was built for 50 million annual passengers. Last year, it handled 82.3 million, and that number is expected to keep growing.

DIA’s strategic plan includes Vision 100, focused on preparing the airport to serve 100 million annual passengers in the next several years. Operation 2045 is focused on preparing the airport for its 50th birthday in 2045 with an expected 120 million annual passengers.

“We are dealing with an airport that has doubled in business, and we are building to accommodate that,” says Washington.

A training center for careers in aviation and for small contractors to become primes will open next year.
Rendering courtesy DIA

Overcoming Flight Bumps

The Great Hall project hit turbulence early on; DIA in 2019 terminated a public-private partnership after 13 months of work. DIA paid $184 million to the Ferrovial-led team after using a convenience clause to terminate the contract.

When Washington became CEO in 2021, “I wanted to do a lessons learned document” on the P3 attempt, he says. “Then we drove on.”

A joint venture led by the Hensel Phelps and Stantec team stepped in to get the project back on track with a construction manager-general contractor delivery model, says Washington. “It’s working for us; we are $50 million under budget.”

The 227,000-sq-ft first phase focused on updating the terminal’s central portion, from modernizing ticketing and check-in to upgrading mechanical systems on three levels. Key elements included converting the central section into a four-pod style layout with dynamic new signage and nearly 90 self-service kiosks. The expanded 21,000-sq-ft curbside floorplate includes new restrooms, a new curtain wall and insulated metal panels.

Structural slab extensions were engineered to capture excess capacity in existing columns and foundations supporting a cantilevered floor. Expansion of the Level 6 floor slab accommodates the future addition of more ticketing, check-in and security screening areas.

The new security checkpoints offer upgraded technology and faster throughput.
Rendering courtesy DIA

The Hensel Phelps-Stantec team “took over the documents for the portion already under construction,” says Carl Hole, Stantec senior principal. “We spent six months going over them to determine what had been done and what needed to be done, and then finding out what should be changed from a phasing standpoint or a schedule standpoint.”

Tyler Tubbs, Hensel Phelps operations manager, adds that “there were a handful of subcontractors and trade partners that were already with the prior team. They had acquired a lot of materials and were already moving forward. So we brought those trade partners on board with us to get going. It was as efficient as it could be with continuing the path right out of the gate.”

VanHercke notes that the changeover in teams occurred right before the pandemic. But through the collaborative process, “we came up with some great value engineering solutions.” Those included modularized ticketing pods that could be built off site, modified pathways and upgraded wayfinding for passengers to navigate around construction and looking at materials that were readily available to combat supply chain issues, he says.

Laser scanning helped determine existing site conditions and progress of previous work. Key stakeholders were co-located to improve communication and collaboration. “It’s been a collaborative process; we’re all in the same building,” says Michael Sheehan, the airport’s senior vice president for special projects. “We identified ways to get ahead of schedule.”

The team completed its $160-million contract for Phase 1 in 2021. The phase added 31,000 sq ft of new space and renovated 158,500 sq ft of existing space. In the $162-million, 100,000-sq-ft Phase 2, the team built the first of two new security checkpoints on Level 6, widened the balcony approximately 40 ft, increased security with ballistic glass and added a new elevator and triple escalator that takes screened passengers from Level 6 to Level 4, where they can take the people mover to the gates.

To accommodate the space required for the checkpoint’s new equipment on Level 6, Stantec and Martin/Martin designed a 40-ft extension of the existing slab-on-metal deck along with a composite hybrid moment frame upgrade to the existing structural columns and beams. Crews placed two level-height cast-in-place concrete columns to upgrade the existing structure rather than using structural steel plate.

Sheehan notes one example of collaborative problem-solving: “We had to identify how our triple escalator was going to get passengers down to the train. We were working over our existing train that goes from the terminal to the concourses. That work is surgical in nature, and so any work done on that train platform is very difficult with an operating terminal. So one of the things [for which] I give Hensel Phelps all the credit is the four new elevators. We have been out there with two on the west operational, and the two on the east will be operational by the end of September.”

The team identified a location that minimized the impact to train operations that passengers would experience, he says.

The anticipated “Living Room” part of the Great Hall will feature a striking tree sculpture.
Rendering courtesy DIA

Collaboration with airlines also was vital. “The airline relocations was a big deal,” says Tubbs, noting that several airlines are temporarily relocated a floor down from the renovated Level 6. “Every time we do that, it’s a monumental effort. It requires lots of overnight shifts and one airline at a time, one tenant at a time, for all the other systems and multiple levels to all go together.”

The final phase, marked by the east security checkpoint that opened this August, is currently 5 months ahead of overall completion. “Getting ahead of the summer rush was huge,” Sheehan says. Work around the opened checkpoint remains. “We’re still working on the elevators on the east side,” says Sheehan. “We have a temporary elevator out there. We’re not actually done until the end of this year.”

The rest of the final $1.3-billion phase, scheduled to complete in 2027, includes renovating the airline check-in facilities on the south end of Level 6 and creating a new meet/greet area for domestic and international arrivals.

“The south end will be spectacular,” says Washington. Dubbed the Living Room, it will be filled with a variety of seating and dining options plus four security lanes to serve travelers arriving via Denver city transit. A 70-ft-tall, 60-ft-wide cottonwood tree sculpture of resin and stainless steel, with over 30,000 crystals draped throughout its canopy, will serve as a landmark for the Living Room.

Early next year, the airport expects to hit another milestone with the first session at the Center of Equity and Excellence in Aviation, to be located on the fourth floor of the 433,000-sq-ft Westin Hotel that opened in 2015 at the airport.

“The fourth floor was a shell space. It wasn’t built out,” says Jim Starling, DIA’s chief construction and infrastructure officer. “So we went in there, and we’ve been building over the last year to build the center.” Sky Blue Builders is building the center with oversight by the Hensel Phelps team.

The center will offer aviation education from levels of grade school to senior leadership, a space for research and innovation and a business development academy to train small businesses to become prime contractors, says Washington. It will also offer child care for participating trainees.

DIA expects annual passenger numbers to eventually hit 120 million.
Rendering courtesy DIA

Once and Future Projects

Numerous other projects have been recently completed at the airport, including a more than $1-billion project that added 10 gates and 12 hold rooms to Concourse B and 16 gates and 20 hold rooms at Concourse C, opened in 2023 and built by a joint venture of Holder and FCI. The 767,000-sq-ft expansion included apron paving work and sustainable measures such as artificial lighting reduction, exhaust and outdoor air energy recovery, a high-efficiency central plant and a rooftop photovoltaic system.

WSP oversaw the delivery of 39 gates across concourse expansions and also provided program management support consisting of 38 task orders, best practices and redevelopment of the PM procedures. “In a big program like this, you have to have a set of standards and legislative items for what you’re allowed to do,”

says Indhira Figuereo Blaney, WPS national aviation leader. “Governance, delivery mechanisms, standards between construction and design versus operations and airlines—all that had to agree with each other. There has to be a bible for continuity, so that even when teams change, there’s still a path for doing business without recreating the wheel.”

In 2021, Hensel Phelps with lead designer Burns & McDonnell upgraded a central utility plant that now has 20,000 tons of chilled water capacity, 214 MMBtu per hour of hot water capacity and an 8.97-million-sq-ft service area capability. The system supplies chilled and hot water to seven airport buildings and served as a key enabler for subsequent airport construction.

Last year, PCL Construction completed 18 glycol recycling systems for DIA. The systems allow low-concentration glycol to be extracted from stormwater and reused. The airport is now able to recycle 99% of glycol used in deicing processes.

PCL is also working on the airport’s $500-million baggage system upgrades. Work includes replacing explosive-detection screening machines with 25 newer models that have higher throughput and modernizing and upgrading conveyors, high-speed diverters and other equipment.

“We started out in what we call our ‘mod’ one, the very north end of the terminal, and we’re working on the west and the east side,” says Sheehan. “The work is very surgical in nature because we have two baggage loops in each of those sections stacked over each other. So we’re going into a 30-year-old facility and maintaining the operations while taking a loop out of service. Then we’re bringing in these very large units, while we’ve got structural upgrades, mechanical, electrical, plumbing, life safety systems, [and] clearing the right-of-way to get in these new large units and then putting everything back together.”

The new system will be able to handle 674 bags per hour versus 400 bags, he adds.

The airport’s 2024-2035 capital program will consist of some $8 billion in projects, says Starling, and possibly around $18 billion by 2045 for a projected 120 million travelers a year. Planning is underway to add a seventh runway by 2035 and potentially an eighth by 2045.

Jacobs is providing program management support services for the planned consolidated rent-a-car facility (ConRAC) and common transportation system (CTS), estimated to cost approximately $1 billion.

“It will be the largest gas fueling station in Colorado,” says VanHercke, adding that DIA wants it to be fully electrified. “There will be massive electric vehicle charging infrastructure. Our initial tasks are to sit down with the city and county and industry to understand the best way to roll it out.”

Starling says the airport continues to expand its solar energy capacity in anticipation of such projects. “So we currently have about 50 megawatts of solar power, and [a new] solar array project will add another 18 megawatts.”

DIA this spring also began the federal environmental review process for a $15-million study to explore options for improving traffic flow, reducing congestion and adding transit options on Peña Boulevard, the main access road to the airport and eventually to the ConRAC and CTS.

With 53 square miles of land, DIA is one of the rare U.S. airports with plenty of room to grow. Starling says of the original planners of DIA: “I think they were really looking forward. They were there future-proofing, making sure that we have all this room for whatever may happen.”