Dorchester Park consists of 26 acres in the heart of the city's largest neighborhood. For many that green space is an oasis, a respite from the thundering concrete of busy roads and the rumbling of trains.

It's cooler in these hot summer months than a stoop on the Avenue, its leaves and trees providing shade from the hot sun. It gives dog lovers a place to roam, little leaguers a place to dream, and anyone who needs it a place to escape, even if for just a short walk. And now some of those who love the park most are calling out for help in order to preserve it for the distant future.

On September 28, the baseball diamond at the park will be transformed into the site of the Dorchester Park Gala Celebration, an evening event where the Dorchester Parks Association intends to raise considerable funds for the park. The goal of the night will be to raise $100,000 to $150,000 for a permanent fund to keep the park in good condition. Richard O'Mara, owner of Cedar Groves Garden, is a co-chairman of the group planning the event, which has gathered $45,000 in local donations and is looking for much more.

"My big mouth got us started in it," he said with a laugh. "It started out initially with an announcement at a civic meeting and it has morphed into something a little larger than I initially anticipated. But I am feeling positive about it, the reception has been generally positive and people say we are headed for success."

The association has hired Stone Event Planning, Inc. in Cambridge to help with the actual celebration. The goals of the fundraiser will rest largely on the hopes of getting large sponsorship donations, both for the fundraiser itself and for the parks association in the future.

"The goal is to have a net of $100,000 when all is said and done and the way we are going to do that is (to) approach area businesses and offer sponsorships for the gala," explains O'Mara. "We are going to offer sponsorship rights for the business that wants to put up the most money and their name or logo would go on future mailings and advertisement."

Tickets, a raffle, and an auction will also bring in considerable resources with the goal to bring in $40,000 in auction booklet advertisements, $30,000 in tickets, and an additional $20,000 to $25,000 in auction money. Some of the auction items are already set. One will consist of a weekend at a Boston hotel, including dinner, spa treatment, and a possible sporting event. Another will include dinner for nine at the Parkman House with Mayor Thomas Menino, and hopefully a few other nights with local politicians. A third will be focused on professional sporting events, and a fourth on restaurants across Dorchester.

"Right now we are working on getting our website in order. It isn't online now but hopefully will be ready soon. There is a committed group of people in the community who are dedicated to helping the park to raise money," says Gabrielle Stone, of the Stone Event Planning. "We are really happy and excited to be a part of the event. It is going to be a great experience."

Jane Boyer, the president of the Dorchester Parks Association, says she hopes the event will enable the park to remain a place for the future families of Dorchester to come as much as she uses the park.

"That's my goal: to preserve it for everyone to use," she says, noting that the work of O'Mara has been outstanding. "I can't tell you how many hours he has put in. If it wasn't for Richard, we could not do this. He sees the need to keep Dorchester Park an open space for the community."

Mary Hines, from the Boston Parks Department, has been working with the committee on the process and approving the plans for the event and has been impressed the whole way.

"They did everything by the book. It's a great committee and everyone is so hands-on. It's going to be something nice for everybody in Dorchester," she said.

"These parks really deserve the attention and focus of the people to protect the legacy of the parks," says Lee Kennedy of Lee Kennedy Co., which has already donated to the event. "And with all the building going on, it is just nice to remember we have important green space too."

While the specifics that will guide the trust fund have not been determined, O'Mara envisions a seven member board, with representatives from the parks department, the Dorchester Park Association, an attorney, an accountant, and three other board members. It's a project that will be hard to start, but in the future will generate income on its own to "ensure that the green space and the original accuracy of [Frederick Law] Olmsted's design stays intact for the future," O'Mara said.

"It's a community based effort. It's non-political and it's for the benefit of all of the people of Dorchester," he says of the project. "It's just a good park."