Noah Balazs didn't mind wading thigh-deep in the 850-acre Kawai Nui Marsh.

"I'm probably not required to do this, but I like it," said Balazs, 22, as he piled muddy vegetation to create islets for endangered waterbirds, where they would be protected from predators such as mongooses.

"I'm usually the dirtiest and smelliest at the end of the day, which I'm pretty OK with," he said.

Balazs, from Massachusetts, is co-leader of 16 Mainland students from Putney Student Travel, a Vermont-based program that sends students across the globe for community service.

For nearly eight years, the program has brought in student groups, primarily from the Midwest and eastern states. Students pay their own way, and besides performing volunteer work, they get to do such things as take surfing lessons and learn traditional Hawaiian dances.

Putney students and inmates from the Women's Community Correctional Center in Kailua have spent the past three weeks cutting down ailing vegetation, replacing alien species with native plants, building trails and forming pathways of mud to create a habitat for wetland birds at the marsh's Na Pohaku O Hauwahine site.

Brett Richardson, 16, a high school student from Pennsylvania, said he was looking for summer work, so he decided to visit Hawai'i and give back, too. Although the work can be grueling at times, he said it's still enjoyable.

"I get to see a beautiful, beautiful state, and I get to see the work that I've done, and I get to learn some lessons about how to work hard, how to be diligent, and how to work in groups," Richardson said.

Chuck Burrows, 74, president of 'Ahahui Malama I Ka Lokahi, a nonprofit organization dedicated to preserving the native ecosystem, said the community service program helps others understand Hawai'i's heritage and restores the ahupua'a for future generations.

It also helps some WCCC inmates get in touch with their Hawaiian roots and speeds up the rehabilitation process, he said.

Balazs, a graduate student in elementary education and a first-grade teacher, said volunteering is worthwhile.

He said volunteers feel good when they see the changes they've made.

"It's especially important for the teenagers to see tangible results or else they don't feel like they are getting anything done," he said. "So in a place like this that has been transformed by our being here, and our work here, it's so nice to be able to see that we've made a difference."

The group has helped out at least once or twice a week, six hours each day, putting in a total of 90 hours during their stay. They leave today.

Balazs said many people who come to Hawai'i just see the tourist aspect — the beaches and resorts — but that getting involved in the community provides a different perspective.

"It's a community service trip and we can hit the beaches to wash all this (dirt) off — it's a real nice combination," he said. "But to come here and do something like this, you actually get to meet real people who live here and who are doing this kind of important work; it's an aspect that's totally missed by people who just come to tan."