The state is clearing debris from flood-ravaged Kailua Reservoir dam, drawing both applause and concern from residents along Waimanalo Stream.

"Right now, all we know is they're fixing it temporarily and everybody is happy about that," said Arden Auld, who is among several residents worried about the long-term plans for the reservoir.

Through next week, cleanup crews will be removing rocks, branches and other debris from the reservoir and its other drainageways, said Janelle Saneishi, spokeswoman for the state Department of Agriculture, which is responsible for the site.

Discussions on the future of the reservoir — an abandoned and usually empty earthen dam — have yet to take place, Saneishi said.

"Right now, our focus is on the immediate remediation of the reservoir," Saneishi said. "The future of the reservoir hasn't been determined yet."

The state has been keenly focused on dams since a fatal breach at the Kaloko Reservoir dam on Kaua'i last month claimed seven lives. Officials launched inspections of the state's more than 130 dams, starting on Kaua'i and continuing on Maui, O'ahu and the Big Island.

Inspections on Kaua'i showed no imminent emergencies, officials said, but the full inspection reports have not been released. The status of inspections on other islands was not immediately available.

Attention to the abandoned Kailua dam came when it flooded and overflowed on April 2 after heavy rains. The flooding forced the evacuation of about a dozen families for several hours.

The overflow problem was exacerbated when water flowing through a damaged underground drainage pipe, which serves as the main outflow when the dam fills, spewed upward and created a 25-foot sinkhole.

A large java plum tree fell into the sinkhole, cutting in half the drainage capacity of the culvert, said Kimberly Kalama, whose property borders the culvert and the reservoir.

Neglect apparently led to overgrown vegetation in the reservoir, Kalama said, noting it likely contributed to the rapid filling during the recent storm.

Hawai'i National Guard personnel hauled the java plum tree from the sinkhole earlier this week, Saneishi said. She described the ongoing debris clearing as "a partial breach, a controlled breach, so the reservoir doesn't retain water."

The goal, Saneishi said, is to allow the water to move in a more natural flow from the reservoir to the stream during heavy rain.

Longtime area resident Lani Lapera is among those with mixed feelings about the attention being paid to the reservoir.

"We're grateful for what's being done now," she said. "But for the long term, we would like to know what they plan to do."

Kalama said the storm of two weekends ago could have been disastrous if not for the reservoir. Area residents estimated that it took about 11 minutes for the water in the dam to rise to the 10-foot level and brim the top.

"That's a flash flood," she said. "If this reservoir wasn't here to impound that amount of water, what do you think would have happened downstream?"

The reservoir, which can hold about 5 million gallons of water, was built in the 1930s for irrigation but was decommissioned in 1993 after the 60-million-gallon Waimanalo Reservoir was built.

Reach Gordon Y.K. Pang at gpang@honoluluadvertiser.com.