Marin County’s airport in Novato is in line to get a nearly $2 million upgrade to its nearly 5-decade-old runway, but an FAA decision on whether the runway will get a short or a long extension to better-handle larger aircraft is still on approach.

The Marin County Board of Supervisors on June 20 approved plans to rehabilitate the 3,300-foot-by-75-foot runway and several taxiways at Gnoss Field Airport, airport code DVO, located three miles north of Novato.

“The improvements will provide a better experience for the airport’s users and will also open up new possibilities for future aviation services,” said Dan Jensen, airport manager. “This is a much-needed step in ensuring the longevity and functionality of Gnoss Field.”

Meanwhile, the FAA is considering input from a May 18 workshop on a proposed runway extension. A 1997 Airport Master Plan update called for a 1,100-foot extension, making the total length 4,400 feet, at an estimated cost at the time of $16 million, including a significant amount for environmental-impact review and mitigation, according to Julian Kaelon, a spokesman for the county Department of Public Works. A 4,400-foot runway was part of the environmental impact statement the FAA released on the project in 2014.

The FAA updated the document in May 2016, recommending only a 300-foot extension, to 3,600 feet, based on a study that showed fewer existing and forecast takeoffs and landings from larger aircraft.

Based on the workshop last month, the FAA has called for more information, including asking to interview pilots for owners of jets based at Gnoss, Kaelon said. That will go into determining whether there is enough usage by “critical aircraft” that need the longer runways, such as a Cessna 525 (Citation or CitationJet). That benchmark is at least 500 takeoffs and landings annually.

Open around the clock, Gnoss Field covers 120 acres and handles about 85,500 flight operations per year and is a popular with business and pleasure pilots.

The runway was built in 1968, and upgrades to the airport have been under study for nearly three decades. But the runway rehabilitation project became more critical when a June 2016 inspection by Mead & Hunt found the surface had deteriorated enough — cracking and sagging, with previous crack patches failing — to need work to continue serving the private pilots and charters that use it.

The runway upgrade is estimated to cost $1.68 million plus $225,000 for construction management and testing. An FAA grant would cover 90 percent. The county would finance the rest over four years, paid for mainly by hangar fees.

Bidding on the project is set to open Aug. 2 at 2:30 p.m. If the FAA likes the bids and approves the grant, the county could start the job as early as mid-September.

Because this is more than just repaving, the airport would have to close for 30–40 days, according to the county. Crews will rip up the pavement and its base then reconstruct them into a smoother surface with better drainage. Work also will include sections of several taxiways and new pavement markings.

The county will work with tenants on options for the shutdown.