ESSEX — In her day job working on an environmental radio show, Ashley Ahearn is constantly immersed in the effects that people’s environments have on their behavior. It wasn’t until recently, though, that Ahearn realized she’d lost her connection to the environment that had shaped her young life: the Essex River.

The 24-year-old, who left Cape Ann to go to college in Washington, D.C., and has lived in Japan, France and Scotland, is an associate producer for “Living on Earth,” a public radio show that examines environmental issues worldwide.

“You just realize that people are divorced from their environment, or not connected to the places they live,” said Ahearn of her reporting, which often focuses on natural disasters, chemicals or global warming. “I realized that I really missed my roots, and summers on the Essex River were pretty much the most important environmental impact on my life.”

With that realization, Ahearn, who lives in Boston and works in Somerville, began to put together a production of her own: “Down River: Life and Landscape in Essex, Massachusetts.” She’ll air the audio portrait of the town, a compilation of about a dozen interviews with residents, on Nov. 30 at an event hosted by the Essex County Greenbelt Association.

“It was ripe for a story and had some beautiful sound coming from it,” said Ahearn of the river and the town. She traveled from Boston to her parents’ Main Street home each weekend from May to mid-September, toting recording equipment to talk to anyone with ties to the river. She hung out with clammers and chatted with a seventh-grader looking to buy a 10-speed bike from her parents’ yard sale.

Ahearn has been involved with public radio since she was 14 and spent a summer holed up in an office, logging tape and helping with research for a piece about the death of the fishing industry by award-winning radio journalist Sandy Tolan. (Her father, Joe, had an office next door to Tolan’s and volunteered her for the job.)

At Georgetown University in Washington, D.C., Ahearn took only a couple of journalism courses, despite her interest in environmental reporting and radio that the experience with Tolan had sparked. She majored in comparative literature, but as she wrapped up her thesis, decided “no one was going to read it,” and that she wanted to do something with more impact on the public.

A National Public Radio internship on the show “Radio Expeditions” brought Ahearn closer to her goal.

“I realized the potential of radio to take people somewhere,” she said. Two years ago, she was hired by “Living on Earth.”

“Covering a small town is not like working for a national radio program,” Ahearn said. “Nobody had an ulterior motive or any reason to tell me one story or another. It really involved putting in the time and showing an honest interest in their lives, which I think people weren’t expecting.”

Because of Essex’s size, Ahearn was able to quickly get in touch with the people that represented its many faces. She started to call friends, hung out at the Shipbuilding Museum, attended community breakfasts and tapped into her brothers’ job history at Woodman’s.

She asked most people to recount their memories of their first time going downriver. But the best answers came when Ahearn asked her subjects about the boat in which they took that trip, she said. Unlike the luxury boats that some associate with nearby port cities and towns, many Essex residents take their first trip downriver in a leaky makeshift boat, or a clammer’s boat that doubles for weekend outings.

Ahearn said one of the best contacts she made was with Chester Roberts, 87, a lifelong Essex resident who lives near the Gloucester line and has what Ahearn calls “a beautiful baritone voice that kind of resonates on tape.”

His is the first voice on the documentary. The interviews she did with Roberts over the summer spurned an unlikely friendship, where she baked him pies and he lent her books.

“The documentary is only 20 minutes long, but I couldn’t tell you how many hours I put in,” Ahearn said. About a dozen voices are heard; she interviewed twice that many.

One of the most exciting — and scary — parts about the airing next week is the fact that Ahearn will be face-to-face with her subjects, she said, finally getting the personal connection she’s been looking for since her comparative literature thesis.

And the journey was a personal one as well. While Ahearn tried to keep from becoming a part of the piece, as journalistic standards so often dictate, she believes listeners can hear her love for the Essex and the river in the narration she provides. That love was the most important thing that Ahearn learned over her summer on the river.

“I went away to college and moved back to the area, and I’ve been saying to myself that I’m ready to move on,” Ahearn said. “I have that travel itch, but doing this documentary I realized that I need to scratch it now so that I can come back and spend the rest of my life here.”