Mead & Hunt, a national architecture-engineering consulting firm, will soon start construction management services on Napa County Airport in the City of Napa, California. The project involves the rehabilitation of three separate runways at the airport, including the intersection of the primary and secondary crosswind runways. Construction is anticipated to start in April 2019 and end in the fall of the same year.
The runways have gone largely without repair since their original construction in the 1940s, necessitating the extensive rehabilitation. Due to the presence of detrimental subgrade soils throughout the site, the pavement reconstruction project could be costly and time-consuming. Mead & Hunt worked closely with the County of Napa and FAA Western-Pacific Airports Division during the preliminary design phase to identify the pavement rehabilitation and reconstruction alternatives for the project. When the PCC Crack and Seat with asphalt concrete overlay alternative was determined to be the preferable solution, the County filed for a Modification of Airport Standards (MoS) with the FAA. The FAA approved the MoS on April 25, 2018.
The design team worked with the County to develop a multi-phased construction schedule that could be accomplished in one construction season. The phased construction approach will allow the Airport to remain operational throughout the busier summer months. To accomplish this, a temporarily-relocated runway threshold for Runway 36L was developed for the construction to occur in the intersection of Runways 18R/36L and 6/24. The design of the temporary threshold required close coordination with the FAA Air Traffic Organization (ATO) to develop new temporary flight procedures while it was in use. The coordination of the anticipated construction schedule with the FAA ATO occurred early on in the design process. Their input was critical in establishing the construction phasing.
Prior to the design phase, Mead & Hunt also performed an environmental technical study to define a project that had minimal impact to the wetlands and critical habitat zones, particularly prevalent at the Napa County Airport. Mead & Hunt studied existing surface contours using topographical data and determined a project limit that would meet FAA grading requirements without disturbing environmentally sensitive areas. Mead & Hunt worked with the FAA Airport District Office (ADO) to establish a mutual understanding of the advisory circulars and obtain concurrence with the preliminary grading design. This led to FAA determination of the project as Categorically Excluded and allowed the design to commence within a reasonable timeframe.
As part of the public outreach process, Mead & Hunt used an Unmanned Aerial Vehicle (UAV) to document the project site with pictures and video of the runway environment at Napa County Airport. Mead & Hunt received authorization from the FAA to operate the UAV at the Airport and submitted the FAA approval to the manufacture of the UAV to unlock the geofence that exists in airports. The photos and videos generated from this operation have been effectively used for public outreach on the Napa County Airport website, Airport safety training, and temporary airfield configuration packets sent to pilots, control tower staff, emergency staff, and project stakeholders.
Numerous project challenges and tight timeframes combined to make this project demanding—the Mead & Hunt team worked collaboratively with Airport Management to find innovative solutions to each project challenge. According to Greg Baer, Napa County Airport Manager,
Mead & Hunt proactively developed a complex yet workable phasing plan that minimized daily operational impacts for the Airport’s tenants and commercial operators. This, combined with their seamlessly-integrated FAA coordination throughout design, contributed to a smooth and successful process for all involved.
