KAILUA, KONA, Hawai'i — The Kaloko Fishpond seawall is a giant, complex interlocking puzzle of lava rocks that stretches across 250 yards of bay front and across more than three centuries of Hawai'i's history.

The seawall has been in the process of being rebuilt, one stone at a time, since 1998, slowly reviving one of Hawai'i's cultural and spiritual practices along with it.

The rebuilding started off a long-term community-based restoration project, KalokoHonokohau National Historical Park ranger Richard Boston said.

"The park's founding legislation is unique. Its mission is to sustain and revive traditional and cultural practices," Boston said. "We want to develop not just something to look at, but something that brings the old traditions back."

The $1.5 million Kaloko-Honokohau project is the latest aimed at perpetuating one of Hawai'i's greatest engineering feats.

Some fishponds can never be restored. Kona International Airport sits on the site of a fishpond that was swallowed by the 1801 lava flow from Hualalai volcano. So each new project is an opportunity to keep the culture alive.

"Fishponds are one of many vehicles that will lead us back to our culture," said Pii Laeha, fishpond manager at Mauna Lani Bay Hotel & Bungalows resort on the Kohala Coast. "Hawaiians were among the first to practice aquaculture, and the industry today really grew out of that."

Still, with so much time gone and knowledge lost with older generations, Laeha said it is like reinventing the wheel.

"Today's fishponds would have a hard time without modern technology, although we use the same techniques and philosophies as in ancient times. Everything is a balancing act," he said. "Lots of ponds are viable and still working, and there is knowledge out there in the local communities."

Boston agreed the restoration is essentially a local effort, despite the 11-acre Kaloko Fishpond's sitting within a national park that also features house site platforms, petroglyphs, a stone slide and heiau dating to the 13th century.

"The park was established with local community input, and they didn't stop there," he said. "There are lots of challenges in developing fishponds. We have to do everything right. We are reaching out to the local community, and it's not just one person but a group of people here."

When residents realized they were losing much of the coastline to resort development, they pushed the federal government to protect the fishpond once called "the refrigerator of Kona."

Established in 1978, the 630-acre park now is one of the few stretches of unimproved coastline along the 10 miles between Kailua, Kona, and Kona International Airport.

Standing on the seawall and looking north toward the airport affords a view of huge, orange construction trucks and cranes clearing the shoreline. The Kohanaiki subdivision covers 550 acres and boasts $2 billion in real estate sales, Boston said.

Meanwhile, to the south, there are plans to expand Honokohau Harbor by 600 slips, and build 1,800 timeshare units, two hotels, shops, restaurants, a marine science education center and a health/wellness facility.

Boston said the park wants to plant tall screens of native vegetation, more as a sign of respect than to delineate boundaries.

The long-term plan also includes a working pond offering educational experiences for visitors and children, as well as turning a profit as a local food source.

"We're not huge on the tourist map yet," Boston said. "Visitation is a good thing, but that's not our only mission."

He estimates it will take at least another two years to complete the northern end of the wall.

Funding is complicated and coming up short, he said.

A $200,000 grant from Save America's Treasures called for matching funds. Boston said the grant will lapse unless $35,000 is secured by June 1. "And it's not coming from the park service," he said.

The restoration began in 1992 with the removal of nonnative vegetation, and the physical rebuilding began in 1998.

Expert masons have painstakingly put much of the wall back together. But although several of the masons and consultants worked on the wall in their youth, the project has moved slowly.

Workers often are injured, slipping on jagged lava rocks and being pounded by waves, Boston said. The masons also dive along both sides of the wall to retrieve some of the original rocks. It is 30 to 40 feet wide, more than 6 feet high, and is bisected by two channels, or sluice gates.