A day after approving another major development project, the Hawaii Land Use Commission on Friday gave the green light to Hoopili, a 12,000-home master-planned community in west Oahu.

Opponents promised to challenge the decision in court.

The vote was 8 to 1, with Commissioner Jaye Makua dissenting.

The ruling reclassifies a 1,500-acre tract of land in Ewa from agricultural to urban, and allows the development — the largest to come before the commission — to move forward.

The vote ended eight months of arguments before the LUC that pitted project developer, D.R. Horton, against Friends of Makakilo, the Hawaii Sierra Club and Sen. Clayton Hee. More than 100 people showed up to watch or participate in the final six hours of testimony before the vote. Many in the crowd cheered as state officials voted in favor.

Commissioners expressed angst as they described the reasons behind their decisions.

“This has been a very difficult decision,” said Lisa Judge, a commissioner from Maui. “I’ve debated with myself for several months now on a daily basis which way to go. This is not a personal decision. I don’t get to do what Lisa Judge wants to do.”

She and other commissioners said their decision was based on statutory requirements.

Ultimately, commissioners rejected the opponents’ argument that the Land Use Commission lacked constitutional authority to reclassify highly productive farmland for urban use. And they sided with D.R. Horton in their opinion that the need for jobs and housing outweighed arguments about the need to preserve ag land and promote food sustainability.

D.R. Horton argued that there was plenty of agricultural land left in the state to be farmed. And the owners of Aloun Farms, which occupies land slated for development, came out in support of Hoopili, saying they had already found an area where they can relocate.

However, commissioners raised serious concerns about the impact the development would have on traffic. They imposed conditions on the approval that require D.R. Horton to update its traffic assessment to include the impact on congestion if the Honolulu rail project isn’t built, or is shelved. Honolulu was recently rated as having the worst traffic in the country. And the rail project, which is expected to slow the rate of increasing traffic, though not reduce it, is facing two court cases. A leading mayoral candidate, Ben Cayetano, has also vowed to kill the project if elected.

Despite the ruling, the battle over Hoopili is unlikely to end this week. In closing arguments before the commission, Eric Seitz, an attorney for Hee, vowed to take the matter to court.

“I hope I’m not just speaking to the wind here,” he said, referencing rumors that commissioners had already made up their minds prior to Friday’s proceedings. “And I will assure you that if I am, that this matter is not going to be done today, that we will take it into the courts.”

Elizabeth Dunn, an attorney for the Sierra Club, also told Civil Beat that the environmental organization intended to sue, as did Kioni Dudley, who heads Friends of Makakilo.

“The law is really on our side,” Dudley said. “The law is quite clear that (the LUC) must pay attention to the lands that have been under cultivation for the last two years. They’re our highest producing farmlands. It’s just insane.”

He said he was greatly disappointed in the decision.

For critics of the project, who have rallied against the loss of prime farmland, it wasn’t just a disappointing day, but a disappointing week.

The day before, the commission approved Castle & Cooke’s Koa Ridge project, a master-planned community of 5,000 homes planned near Mililani. The Sierra Club has been fighting that development for a decade.

Combined, both projects will displace more than 2,000 acres of ag land, much of it prime acreage, along with some of the state’s largest farms. Hoopili alone is one of the largest developments to move forward in the state.

Both supporters and opponents stressed that Hoopili is one of the most important cases to come before the commission. The project became embroiled in larger policy debates this year about the future of development on Oahu and goals for food sustainability in a state that imports about 90 percent of its food.

And it attracted political heavyweights who came out to testify against the development. In a rare move by a senator, Hee intervened in proceedings to try to stop Hoopili, enlisting well-known attorney, Eric Seitz, to plead the case. Former Hawaii governors, John Waihee and Ben Cayetano, also showed up to testify against the development.

This is the second time that D.R. Horton has gone before the commission. In 2009, the LUC rejected its application in a 5-3 vote because the developer lacked a detailed timeline for construction.

Executives of D.R. Horton applauded Friday’s ruling. Cameron Nekota, executive vice president for the company, said that they were grateful for their supporters and looking forward to moving ahead with the project.

“I’m just happy for our company. I’m really happy for all of our supporters, the thousands of people that have voiced their support for the project and come out to testify, our community task force,” he said. “This really became the community’s plan, not D.R. Horton’s plan.”

He said that the company planned to try to collaborate with opponents as it faces a potential appeal of the decision in court.

“That’s certainly within their right,” he said. “That’s out of our control.”

Kioni Dudley said he was surprised and disappointed by the ruling. He expressed concerns about the development’s traffic impacts, saying that, “I think the people of Hawaii, and especially people on the west side, have really lost today.”

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