No, it’s not your imagination: There are more planes flying over your house these days in Dorchester and Milton.

Construction on a major runway at Logan International Airport is causing an increase in flyovers – and shifts in the patterns the planes follow out of and into East Boston. The situation has gained the attention of Congressman Stephen Lynch and his constituents in Dorchester and Milton.

A project to rebuild the airport’s 4R runway began on May 15 and is expected to continue until the end of this month. The 10,000-foot runway — one of six at Logan—typically handles about half of the take-offs and landings, according to a story in the Boston Globe noting that the project is causing an increase in delays at the airport.

But delays are not the only result of the project. According to Massport, the runway’s temporary closure has had a measurable effect on flight routes, but specific impacts on Dorchester and Milton aren’t completely clear.

“The construction on 4R has led to adjustments to runway usage to accommodate one of our major runways being under construction. This has led to many changes – both increases and decreases – in aircraft traffic overhead in the communities that surround Logan,” the agency stated in a written response.

Complaints of heavy plane traffic in Dorchester and Milton began to accumulate with the introduction of a new flight navigation system at Logan in 2013. A GPS-based NextGen system allows the airport to more precisely plan takeoffs, which means a saving on jet fuel. Critics claim, however, that the system concentrates flight paths on just a few routes. According to US Department of Transportation’s noise-mapping data, the communities feeling the loudest impacts are those around the airport and those under a flight corridor that runs over southeast Dorchester and central Milton.

Lynch, who has been a vocal advocate for aviation reform and serves as a member of the bipartisan Quiet Skies Caucus, thinks that the construction at Logan has concentrated flights over Dorchester and Milton.

“There is a number of upticks that we are seeing right now,” he said in an interview this week. But even without the closed runway, he added, the NextGen navigation system is seriously flawed, and could be doing more harm than noise disruption.

“There are two things going on with the over-flights,” he said. “One is, obviously, the decibel level and the frequency.... It’s basically nonstop, so there’s no letup. Secondly, because these flights are on a very narrow vector, they’re flying at a very tight airspace configuration, which puts all of the emissions directly over the same houses over and over again. We’re very concerned about the health implications for the communities that live beneath that flight line.”

Milton Scene, an online blog, currently features a petition calling on lawmakers to more actively protect communities living under the NextGen flight paths. The document has almost 1,200 signatures, 41 of which have been added since May 15. It reads in part:

“We demand that the right to health and a decent quality of life for citizens living near airports be recognized and prioritized in the [Federal Aviation Administration’s] mission, right after safety, and before efficiency....The damaging impact of the NextGen program’s concentrated flight path was immediately apparent upon its implementation and we ask that new solutions be found that… justly distribute aircraft noise and air pollution across the entire region benefiting from proximity to an airport.”

The site includes another post detailing the suspected buildup of flight traffic over the neighborhood because of construction. With the 4R runway currently out of commission, it reads, “...more flights are coming over the western side of town in a more concentrated pathway, very close together, and for long periods of time – creating a lot more noise than before.”

Last fall, the FAA officially announced it will further study the health and safety effects of NextGen navigation. Lynch said the Quiet Skies Caucus is committed to gathering more information about the communities living below major aviation routes.