A total of 2,640 dwelling units will be affected by noise at or above 65 decibels in 2023, compared to 976 on sound maps for 2015.
The new projections, based on computer modeling, suggest high-decibel noise will affect larger portions of Winooski and Williston, and slightly less of certain parts of South Burlington.
It will also affect small parts of Burlington and Colchester, and a corner of Essex with no homes. A total of 2,655 acres will be within the 65 decibel zone in 2023, according to the projections.
That's according to a 164-page noise exposure study that has been eagerly awaited by residents in the flight path, including some who oppose having the F-35s at the airport.
Officials from BTV, as the airport is known, commissioned the study and posted it online Tuesday. They will hold a press conference at 10 a.m. Wednesday to discuss it.
The F-35 fighter planes will arrive in September at the Vermont Air National Guard hangers at BTV. The guard's F-16 fighter jets were phased out earlier this year.
Properties in high noise zones could be eligible for soundproofing grants and two other programs designed to protect home values. The Federal Aviation Administration grants could funnel close to $100 million to Chittenden County over the next 20 years.
Municipalities will have to pay a 10 percent match for grants to home owners. Individual property owners could qualify for $40,000 to $50,000 in grants for soundproofing with new windows and doors.
Gene Richards, aviation director at the airport, said BTV will apply for the grants after public input. It would be at least a year before any money flows, he said.
The findings aren't a surprise, he suggested. They are similar to a 2013 study about the possible impact of the F-35s at the airport. He reiterated that the city would not seek federal money to demolish more homes, which has been a controversial mitigation strategy.
Since 1989, the airport has razed 200 homes in South Burlington with FAA grants. Between 2007 and 2019, those grants totaled $32 million.
Critics of the demolitions lamented the loss of affordable housing stock. In response, Burlington Mayor Miro Weinberger and other city officials switched direction.
Airport officials will pursue three types of grants based on the new noise projections, according to Richards. In addition to sound insulation, they will pursue an FAA grant designed to compensate home owners for decline in property values due to noise. Eligible property owners could receive grants equal to the difference when a sale price is below the appraised value of their home.
A third grant program would allow the airport to buy eligible homes, noise-proof them, and resell them on the open market.
All three programs are designed to improve housing stock, said Richards.
He acknowledged that community leaders have expressed worry about noise from F-35s at the airport, which is located just three miles from downtown Burlington in a heavily populated area.
"They have concerns, obviously, about the potential for louder noise and affordable housing and preserving it in their community and making sure that it's viable and livable," Richards said. "And you know, that’s been a constant concern for everybody in our community."
Grants would be allocated first to the most noise-affected properties and flow from there, added Nicholas Longo, BTV's deputy director of aviation. Some would have to wait.
"The property owners need to understand that we are moving forward very quickly in this process, but depending on your geographic location within the contour lines, it may be many years before you receive federal funding to mitigate,” Longo said.
Commercial properties would not generally be eligible for the grants. Schools and other public use buildings would be — but with a 10 percent match.
Chamberlin Elementary School, near the airport, sits in the 65 decibel zone, according to the new map. School and airport officials are discussing soundproofing grants.
The new report also includes data for 2018, but noted that it was an atypical year for several reasons. Runway construction and phase-out of the F-16s led to less noise than is typical, according to the report. The 2015 data presents a better baseline to compare sound levels from F-16s versus F-35s, airport officials said.
In addition to the press conference, the airport will host an open house about the noise exposure maps, also on Wednesday, from 5 to 7 p.m. on the mezzanine level. Another open house will take place from 5 to 7 p.m. Thursday at the O'Brien Community Center in Winooski.