HANAMA'ULU, Kaua'i — Koloa residents are arguing for the protection of the dense archaeology of a rocky, undeveloped 127 acres in the heart of the Koloa-Po'ipu area.

The Eric A. Knudsen Trust has asked the Land Use Commission, whose hearings on the issue are under way, to change the state land use designation of the area from agriculture to urban, which it says will add 100 units to the 500 that can be built under current zoning. The trust has proposed a 203-acre development called the Village at Po'ipu on this property and adjacent land that is already zoned for development.

Most of the land would be used for residential development, but the trust has proposed protecting roughly 10 percent of the area in archaeological reserves — considerably more than most neighboring developers have been required to protect. But some of their neighbors argue that's not enough.

"There is a treasure trove of wahi kupuna — archaeological sites — here. It is the last intact portion of the Koloa Field System," said Koloa resident Ted Blake. "Does it make sense to do data recovery, destroy it, and I gotta go read about it in the archives?"

More than 80 people participated Thursday in a Land Use Commission field trip to the site, in which archaeologist Hal Hammatt, of Cultural Surveys Hawai'i, described complexes of ancient agricultural fields, irrigation channels, house sites, religious sites and more. The daylong field trip was launched with a series of chants and prayers by members of the Hawaiian community.

The Kaua'i County Council two weeks ago passed a resolution calling on the commission not to change the land use district. The county's Historic Preservation Review Commission has taken a similar position, recognizing the historic significance of the site "in its totality."

The state Office of Hawaiian Affairs has intervened in the Land Use Commission proceeding.

"We want to preserve these archaeological sites. They have great cultural, historical and spiritual importance," said OHA attorney Sherry Broder.

Don Cataluna, OHA board member from Kaua'i who lives in Koloa, said the area has been preserved thus far because it is so rocky that sugar cane growers didn't bulldoze and farm it and nobody else wanted to build there. But there is evidence that in early Hawaiian days — continuing well into the 1800s — it was a vibrant agricultural area.

The archaeological firm Cultural Surveys Hawai'i found 16 old 'auwai, or irrigation channels, all dating to before the sugar era, but some of which were used unmodified to irrigate sugar. The site includes numerous ancient house sites and stone-lined farming plots. It was part of the Koloa Field System, an irrigated agricultural complex fed by Waikomo Stream that covered 700 acres — one of the largest in the Hawaiian archipelago.

"This is what the Polynesian Cultural Center replicates, but we've got the real deal here," Blake said.

Area resident Rupert Rowe, who wants the area preserved, said owls fly regularly to and from the property, which he said is culturally significant.

"You must protect the past. The past is the future. The future is the present," Rowe said. He is part of a group that preserves a large heiau makai of the proposed development, but which he said is intricately connected culturally to the sites on the Village at Po'ipu properties.

Besides the history of the place, there's a question about the community's ability to handle the additional residential development.

"We've got 4,000 units coming up. We don't need any more," Blake said.

Reach Jan TenBruggencate at jant@honoluluadvertiser.com.