In the middle of Ashbridge Park – a 28-acre oasis of green open space adjacent to the bustle of Montgomery Avenue in Rosemont – Bill Young sat on a bench and watched a steady parade of his neighbors walk their dogs or push baby strollers underneath a giant ginkgo tree.

Young, president of the Friends of Ashbridge Park, pointed to all the improvements made in the decade since residents defeated a Lower Merion School District plan to turn the park into a bus depot – a large playground, new trees in the arboretum, upgrades to the 1700s mansion, and a stone pathway.

"For a lot of people, it is a sacred space," he said of the park that was deeded to the township in 1940 by Emily Ashbridge. The bucolic space was the remaining piece of the family's dairy farm that had been the center of Rosemont for more than a century.

Now Young and his allies are fighting to save the historic property yet again, as school leaders in Lower Merion weigh a proposal to acquire the park, along with a nearby Islamic center currently for sale, as part of a new middle- or elementary-school complex, to deal with an ongoing crisis of rising enrollment.

That Lower Merion is considering the popular park – even raising the possibility of using eminent domain – shows the seriousness of the classroom crunch in a district that, by raw numbers, is the fastest growing in Pennsylvania. While enrollment in the Main Line district had plunged to about 5,000 amid the "baby bust" years of the 1980s, parents lured by Lower Merion's top academic rankings and a recent development boom have brought the student population back to nearly 8,600, and it's expected to hit 9,300 in the next decade.

With the affluent Montgomery County district racing to make a decision on building a new school or adding to several existing ones by the end of the year, officials are sending mixed signals about the seriousness of the proposal to buy the 21-acre Foundation for Islamic Education for a new school and use Ashbridge Park for a track and athletic fields.

Robin Vann Lynch, president of the Lower Merion School Board, said "we would likely move in that direction" of a brand new school – possibly a middle school that would incorporate grades 5-8 – and acquiring the park if experts say that plan is feasible.

But the school superintendent, Robert Copeland, threw cold water on the Ashbridge Park plan, noting that a 1940 deed restriction requiring the property forever remain parkland — and specifically forbids liquor, lotteries, Sunday games, and any sports with more than four people — would likely provoke a long legal battle. "I don't believe that we have time to go in a direction that is not cooperative," he said.

While other districts have taken property they need for expansion — Phoenixville provoked a battle with a family that owned a golf club that it eventually acquired — securing publicly owned land by eminent domain could be even trickier.

Since the spring, Copeland and a school board committee have been looking at a complicated array of options that include building a third middle school and expanding all three by adding the 5th grade; constructing Lower Merion's seventh elementary school and adding the 6th grade to all seven facilities; or building modular classrooms and other additions that would help expand enrollment at the most crowded schools such as Penn Wynne Elementary in Wynnewood.

Copeland said building a new middle or elementary school would cost Lower Merion – which has also been embroiled in a court battle over recent property tax increases – at least $58 million and possibly close to $90 million, depending on the plan, while the expansion plan is the least pricey option at $23 to $28 million.

But each of those plans faces other major hurdles as well as neighborhood opposition. As an older, fully built-out suburb, Lower Merion doesn't have large open tracts for a new school, and proposals to expand existing schools like Penn Wynne drew protests at a September school board meeting from parents who say they'll lose outdoor space for students to play, the construction will be disruptive, and their kids will get less attention in a "mega school."

At another board meeting earlier this month, Copeland sparked anger and concern among residents who live near Ashbridge Park on the opposite side of the sprawling district from Penn Wynne when asked about the 77-year-old deed restrictions. "Sometimes deeds are broken," he said and cited the lengthy battle that moved the Barnes Museum out of Lower Merion. Some 80 people came the next night to an emergency meeting called by the Friends of Ashbridge Park to rally opposition.

With half of Lower Merion's 14 township commissioner slots on the ballot in next week's election, the Ashbridge Park/Islamic center plan has quickly become a political hot potato. Commissioner Philip S. Rosenzweig, whose ward includes the park, has made opposing the district's Ashbridge Park option a cornerstone of his re-election campaign. "I said we'll lay our bodies down before that happens," he said of the proposal.

"This may be a cure worse than the disease in this situation," agreed Daniel S. Bernheim, president of the township board of commissioners, who supports the concept of a new school but sees little appetite for surrendering a widely used township park.

Rosenzweig said, "Any of these proposed uses would destroy the park, denude it of trees and pastoral beauty, wreck the walking path that goes along the perimeter of the park, impact the large playground that draws people from all over Lower Merion and Radnor, and threaten the 1700s historic Ashbridge House. It would just be a devastating end to the park."

His opponent, Andy Gavrin, an estate-planning attorney, agrees. "I honestly think that is the worst possible idea I ever heard. We have this incredible asset that everybody uses. To get rid of that is nonsensical to me."

But political opposition isn't the only problem faced by Copeland and district officials who also noted the Islamic center and the park are on the far western end of the district while most of the enrollment growth has been on the eastern side. They also acknowledge that adding any new facility – middle or elementary school – would raise another politically explosive issue: redistricting.

In Ashbridge Park, Young expressed optimism that residents will beat down this proposal just as they did with the bus depot scheme 10 years ago, and said he's already thinking ahead to future park improvements, such as clearing out fill and concrete barriers that the township has left on a corner of the parcel.

"Once we get past the school thing," Young said, "I'm going to be a warrior" for getting rid of that stuff.