The Vashon Park District’s far-reaching plans to build new athletic fields next to The Harbor School are well under way. Earth-moving vehicles and crews are on the site daily, beginning the work of transforming the once lumpy land into an expansive surface that can accommodate soccer players and baseball teams.

At the same time, another drama has also been unfolding, touched off by a neighboring landowner who contends that the property lines are in dispute.

The police have been called. Lawyers have been contacted. Mediation involving well-known Island businessman Ray Aspiri has been attempted.

So far, none of the efforts has worked, and the park district is moving forward, leaving the neighbors — Gay Rosser and her mother Margaret Rosser — increasingly angry, upset and accusatory.

Last week, the two women showed up at both the Vashon Park District’s board meeting and the Vashon Island School District meeting, where Margaret Rosser, a spry 89-year-old, read a letter asking about what they see as the park district’s latest infraction — the removal of 200 feet of fence that she contends is on the northern boundary of her property.

“We are asking if any of you might be able to give us information or tell us who took out the fencing … and why,” she asked both boards, reading from her letter. The family, she added,plans to file a police report, charging that the act amounted to both vandalism and trespass.

But the park district, which is leasing the property from the school district, says the Rossers have no grounds for their complaint. A thorough analysis of the property — including a survey by well-known Island surveyor Jerry O’Hare — shows that the property in question belongs to the school district, not the Rossers.

The fence near the northern edge of the Rossers’ property came down, park district officials said, for a simple reason: It was encroaching onto the school district’s land by several feet, blocking the area where crews needed to install erosion-control fencing.

Indeed, some members of the park district board are frustrated and fed up with the Rossers, who have gone to King County officials and the community to press their claims and even crashed a fundraising party for the park district’s project last summer, where they handed out information about the dispute.

“They have been nasty and difficult,” said Bill Ameling, a commissioner on the park district’s board.

“If they had sat down and said, ‘I know we don’t have much legal right, but we’d like some help,’ maybe we’d find a way to give them consideration. But if they want to scream that big government is running over them, like some sort of Tea Party thing, there’s no room for consideration.”

David Hackett, another commissioner, expressed similar frustrations. Since an attempt at mediation in January, he said, Gay Rosser “has spent the last four weeks trying to foul every pond she steps in. She’s called everyone in the county to do what she can to kill the project.”

The issue is simple, Hackett said. “To be absolutely clear, we’re acting on Jerry O’Hare’s survey lines. … Anybody who has looked at (Gay Rosser’s) documents realizes she doesn’t have a leg to stand on.”

The Rossers, however, say they’ve taken the issue to this level only because they feel they’ve been thwarted over and over again in their effort to get some redress. They’ve had to beg for meetings, Gay Rosser said, plead for documents and send e-mail after e-mail.

Gay Rosser, a well-known Islander who serves on the board of the Vashon-Maury Island Community Council and volunteers at the Island’s historical museum, said she wants to be a good neighbor to the parks department and the school district.

“I don’t want to make enemies,” she said. “But we still have to resolve this. It’s a messy situation. We have to get it resolved so that we can sleep well at night.”

Margaret and her late husband Leon Rosser bought their property behind what is now The Harbor School in 1943 from another well-known Island family, the Steens. According to the Rossers, the transaction included a long sliver of land that extended from the highway to their five-acre parcel behind The Harbor School — a sliver that is now their 100-foot-long gravel driveway.

A few years later, when the school district purchased land adjacent to the Rossers, then superintendent Hal Barton and Leon Rosser made a deal, Gay Rosser says: The Rossers agreed to give the school district an easement across their sliver of land, allowing the district full use of their driveway; the district, in exchange, gave the Rossers an easement along the eastern edge of the district’s property — allowing the Rossers easy access to the northern reaches of their land.

Gay and Margaret Rosser say it was an agreement done the way many things were done in the 1940s — with a smile and a handshake. The Rossers never received any paperwork documenting the transaction; if any documents existed, they added, they would have been stored in school district files.

But Michael Soltman, superintendent of the Vashon Island School District, says he can find no such documents. Indeed, the only document he was able to find were school board minutes from 1957, where, it appears, the school board denied Leon Rosser his request for an easement across school district land.

Neither a title search or O’Hare’s survey indicate the existence of the easement the Rossers say they have on the school district land. And as for the driveway, the Rossers have that wrong, too, he said: It belongs to the school district, with an easement given to the Rossers enabling them to use it as their driveway.

What’s more, O’Hare said, he could find no indication that the easement the Rossers claim they need to access the back of their property has even been used as such. There are tire tracks across it now, but when he and his field man walked the land two years ago, he said, the sod was not compressed at all.

“There’s nothing of record that says they have that easement, and I didn’t see any sign of anyone even using it,” O’Hare said.

Without proof, Soltman said, he can’t give the Rossers a legal easement across the school district’s property; such a move would amount to a gift of public property, something that is against the law, he said. “There’s not a lot of latitude here,” he said.

The back-and-forth has been going on for more than two years. And over the course of the dispute, Gay Rosser — now the legal owner of the property — has amassed a considerable pile of letters, e-mails and documents, some of which she believes offer up proof of her claim. For instance, some of the documents refer to “a certain roadway” that was included in the Rossers’ purchase from the Steens; another document shows the Rossers own 5.03 acres, not five.

Sitting in the modest home she shares with Gay, Margaret Rosser said she feels abused by both the park and school district. “I’m extremely frustrated that someone who feels they have the power thinks that they can run roughshod over the little guy,” she said.

But Aspiri, who acted as a mediator during a two-hour dinner in January, said he thinks a resolution could be reached if the Rossers would budge a little and if the park district would reach out to the family more fully.

Hackett, acting on behalf of the park district, made a significant concession to the Rossers at that meeting, Aspiri said: He told the Rossers the park district wouldn’t tear down the fence along the western edge of their property — even though it encroaches onto the school district’s land — and that they could have access to the back of their property via the district’s parcel, a use agreement, in essence, though not the full legal easement the Rossers maintain they were given some 60 years ago.

“He offered more than anything I anticipated,” Aspiri said of Hackett. “It wasn’t received as nicely as I would have expected.”

At the same time, he said, he believes park district officials have sometimes been harsh with the Rossers, a family, he noted, that has done much for the community over the years.

“They feel like a train has run over them,” Aspiri said. “It seems we should treat them in a neighborly way.”

Both park and school district officials, however, say it would be easier to meet the Rossers half-way if they, too, approached the issue in good faith. The Rossers, for instance, have told the school district they want the 1957 board minutes carbon-dated, to assure that some kind of fraud hasn’t taken place.

Wendy Braicks, the park district’s director, said the conversations with Gay Rosser have grown increasingly difficult over the last year or so.

“After a while, it seemed she was just unwilling to hear what we are saying, and she’s aggressive enough about it that it’s a fairly unpleasant conversation,” Braicks said.

Gay Rosser disagrees. “We want a peaceful resolution,” she said.