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Team Build
New Federal Hangar Required Intense Collaboration
By Kevin Klott
The new aviation hangar on Lake Hood will restore operational capacity for the Department of the Interior’s statewide flying mission performed by US Fish and Wildlife Service, National Park Service, and Bureau of Land Management.
The new aviation hangar on Lake Hood will restore operational capacity for the Department of the Interior’s statewide flying mission performed by US Fish and Wildlife Service, National Park Service, and Bureau of Land Management.
Team Build
New Federal Hangar Required Intense Collaboration
By Kevin Klott

long the shore of Lake Hood Seaplane Base in Anchorage, a new hangar operated by the Department of Interior’s Office of Aviation Services, or OAS, not only replaces a historic, outdated, and damaged hangar but also represents a new era in Alaska aviation.

Substantially completed in November of 2022, the OAS hangar means three Department of Interior agencies—US Fish and Wildlife Service, the National Park Service, and the Bureau of Land Management—are once again fully operational.

It took three years to fully complete the multi-phase project, which included historic preservation, demolition, contamination remediation, an unexpected redesign, supply chain issues, and winter construction.

Despite these challenges, Amy Klein, project manager for US Fish and Wildlife Service’s OAS, says team collaboration helped get the job done right.

“I felt like this project exemplified ‘design-build done right,’ with cooperation between everyone from facility staff to stakeholders and owners to the design and construction contractors and subcontractors,” Klein says.

Replacing Outdated, Quake-damaged Hangar
For this project, STG Pacific, Inc., or STGP, partnered with Davis Constructors & Engineers, Inc. on a joint venture Small Business Administration 8(a) entity contract from the US Fish and Wildlife Service to design and build the new hangar.

The agencies needed an updated place to store and maintain airplanes after the magnitude 7.1 earthquake in November 2018 damaged doors, walls, and foundation to such an extent that the hangar was no longer safe to use. In addition, the hangar was old and outdated.

structure of the former OAS hangar
The November 30, 2018 earthquake severely compromised the structure of the former OAS hangar, which was already in need of renovation. A new hangar was constructed on the same property.
The hangar had served as a central hub for multiple government agencies’ small planes working in rural Alaska since 1950. It was originally a single Quonset hut-style building, but over time more sections were added. When the earthquake arrived, bringing violent shaking of both the ground and its shallow water table, it spelled doom for the hangar.

Seismic, snow, and wind loading are what drove the structural and foundational design of the new hangar, says STGP Project Manager Mack Pennington. CRW Engineering Group, Inc. completed the design.

“CRW structural engineers helped mitigate seismic risk by designing a large concrete spread footing with sizable grade beams and a structural slab-on-grade hangar floor,” he says. “This frost-protected shallow foundation assists in mitigating the risks of undesirable soils in the area and a shallow water table from Lake Hood.”

Pennington says the new hangar is a far cry from the old one.

“This one is on a whole new level as far as performance capabilities,” he says.

Three-Phase Approach
The joint venture secured the contract in August 2020 with the existing hangar still standing on the southern shore of Lake Hood Seaplane Base. The hangar was so old that it was part of the historic Lake Hood District.

That alone foretold a unique project for the team, a multi-phase path to complete a design-build format that included first working with the State Historic Preservation Office followed by demolition and environmental remediation for asbestos, lead-based paint, and contaminated soil, and finally designing and building the new hangar.

To get the job done effectively, STGP Davis JV selected RIM Architects, LLC to lead the design effort. Prior to demolition in September 2020, the team worked closely with the US Fish and Wildlife Service and the State Historical Preservation Office.

new storage facility for the Department of Interior’s Office of Aviation Services
In the fall, STG Pacific-Davis JV completed a new storage facility for the Department of Interior’s Office of Aviation Services to house a fleet of small propeller aircraft in a climate-controlled environment at Lake Hood Seaplane Base in Anchorage.
“This was a large risk to the contractor due to the possibility that, if it was determined the existing hangar was a historical structure, it would not be allowed to be demolished,” says Jason Arnold, owner of RIM.

“The team moved quickly on day one of the project, enlisting the services of a local archeologist to ensure that the project adhered to all requirements of the National Historic Preservation Act (Section 106) and obtain a final determination that the hangar would be allowed to be demolished without adversely affecting the context of the historic district.”

Meanwhile, the team was busy designing the new hangar. It started with the conceptual design in September 2020 and ended with the complete design in April 2021.

Throughout the winter of 2020, the team prepared environmental planning documents and work plans so it would be ready to begin that work immediately in the spring. Part of that work took place during the demolition, Pennington says.

“We started on the environmental work immediately after in May of 2021 with the contaminated soil beneath the old hangar,” he says.

And that’s when things got complicated.

new hangar with airplanes
The new hangar meets or exceeds the functional and operational expectations for the facility. Its greater height, increased from 27 feet to 41 feet, accommodates the current fleet of aircraft in the smaller East-West bay and a hoist to change out landing gear in the main bay.
Building Site Challenges
After careful demolition of the existing hangar, the STGP Davis team, including Brice Environmental, discovered larger-than-expected quantities of contaminated soil for the proposed location and the site needed to be moved.

“We had very little wiggle room,” says Pennington.

This discovery was cost prohibitive to the owner and, without a quick solution, would have immediately stopped the project.

Arnold says, “We came together as a true design-build team, swiftly explored options, and agreed that the building footprint could be relocated on the larger overall site to avoid the extent of the contaminated soil. This option allowed the project to continue to move forward, but the team had to contend with other side-effects, to include reconfiguration of existing underground utilities and more carefully controlling the slope around the building.”

Ultimately, the team was successful in overcoming these hurdles by moving the site roughly 200 feet south on the same lot, with just 20 to 25 feet to spare. Moving the site also helped alleviate concerns the FAA had with the proximity of the hangar to Lake Hood sight lines from the Air Traffic Control Tower.

“RIM is proud that the design and construction process was a collaborative effort and that it was able to overcome some very serious challenges,” Arnold says.

Collaboration Brings Success
The new climate-controlled hangar will provide maintenance and logistical support for more than thirty-five aircraft completing more than 8,000 hours of flying missions across Alaska, according to US Fish and Wildlife Service. It increases the storage height from 27 feet to 41 feet and decreases the amount of time and resources it takes to maintain airplanes outside.

The hangar design is compact, featuring one large bay and four smaller bays with support spaces. It is oriented to open to the existing airfield so it can be accessed quickly at times when adverse weather is imminent, as opposed to moving and shuffling planes around to fit inside one big bay.

“Now the agency has much more flexibility to repair aircrafts in the fleet in a seismically challenging region and to shelter aviation resources safely in the harsh climate,” Arnold says.

Pennington is pleased with the project and the entire project team.

“Both the team at the Fish and Wildlife Service and the OAS were engaged throughout the life of this project. They really created a collaborative environment,” Pennington says.

Growing up in Anchorage, he understands how small aircraft provide vital links across the state.

Pennington says, “Being able to support this large fleet of aircraft for the OAS team and its different agencies was very rewarding, to ultimately provide a new hangar space, improve their operational capacity, and make it easier for them to support their mission.”

Kevin Klott is a freelance writer who lives in Anchorage. Photos provided by STG Pacific, Inc.