A stubborn brushfire that burned about 500 acres toward the front of Makaha Valley appears to be the first deliberately set fire of 2006, fire officials said yesterday.

The blaze, which started Tuesday night and kept firefighters busy most of yesterday, signals an ominous start to the new year for an area that was plagued by a record number of deliberately set brushfires last year. The fire was mostly extinguished by late yesterday afternoon.

Fire Capt. Kenison Tejada said fireworks might have been a factor given the remote location and the timing just after New Year's Eve.

John DeSoto, a former City Council chairman who lives toward the back of Makaha Valley, said he and his wife noticed the fire on their drive home Tuesday night.

"It was just a small fire when we first saw it but it went berserko in a matter of minutes," DeSoto said. "You know what happened last year. If it turns out to be a dry spring and summer, given the amount of rain we had during the fall and all of the foliage that results from it, we could be in for another bad season again."

Speculation among DeSoto's neighbors is that the fire is the result of someone igniting fireworks in the area.

"We have no proof, but it stands to reason," DeSoto said.

The brushfire scorched a mile-long area on the west side of Makaha Valley, burning off all the green and brown grass cover, along with hale koa scrub brush. From Farrington Highway, the charred earth extended along Kili Drive up to a large water tank.

The area burned had no structures, and firefighters struggled to control it because of the steep slopes and remote location. Tejada said it could have been a small fire, but winds caught it and sent it up the slope quickly.

Approximately 80 firefighters fought the blaze Tuesday night and by yesterday morning, helicopters had to perform water drops to douse the flames while about 30 firefighters on the ground helped snuff out the fire.

DeSoto said that on New Year's Eve the number of illegal aerial fireworks set off in the area was "surprising." So, too, were the number of fireworks appearing along homeless encampments at Kea'au Beach Park and at the front of Makaha Valley along Farrington Highway, he said.

During the first several hours, he kept a wary eye on the blaze because kona winds were pushing it deeper into the valley toward twin residential condominium towers on the west side. But later in the evening, trade winds returned and pushed the blaze back toward the ocean, he said.

He credited firefighters for keeping the blaze in check along the base of the steep slopes on the west side of the valley.

"It came right up to the edge of the towers," he said.

In 2005, arsonists set more than 700 brushfires on O'ahu. Seven arrests were made, but only one case is being prosecuted, in federal court.

Cynthia Rezentes, chairwoman of the Wai'anae Coast Neighborhood Board, yesterday said she was disappointed in the lack of prosecutions after reading an Advertiser report on the issue.

"It's very discouraging because a lot of people in our community don't want to get involved," Rezentes said. "But this past summer and fall the community did rally with members of the fire and police departments and made an effort to come forward with what they knew about some of the people responsible for the fires — and nothing came of it."

Rezentes said some of the rain last fall that finally helped bring an end to what seemed like an endless series of brushfires along the Wai'anae Coast has resulted in large amounts of grass, weeds and other brush to fuel new fires.

And, it has been a relatively dry winter to boot, Rezentes said.

When Rezentes was headed to her home in Ma'ili on Tuesday night, she could see an orange glow in the sky above Makaha Valley.

"It was very dramatic and I knew there had to be a pretty large fire," Rezentes said.

Reach David Waite at dwaite@honoluluadvertiser.com.