City crews examined a large sinkhole today after it appeared on Kanapuu Drive in Kailua Bluffs following Tuesday’s heavy rains.

A portion of Kanapuu Drive near the Kahako Street intersection remains closed, as well as adjacent sidewalks, as crews inspect the sinkhole, on the shoulder of the road near a metal barrier. The sinkhole, which measures at least 15 feet across, also took out part of the sidewalk.

“What we discovered is a sinkhole, quite deep, anywhere from 12 to 15 feet deep,” said Robert Kroning, director of the city’s Department of Design and Construction. “We sent some engineers down the inlet side. They walked in and learned that there has been a collapse in that drain pipe — it’s a drain pipe that we’re talking about, corrugated, metal pipe, 12-foot diameter.”

Kroning said the city does not know how the collapse happened, but that it probably happened over many years or decades of slow corrosion. Engineers were not able to get too close to the collapsed pipe area due to safety reasons, he said.

“We’re in the process of hiring a company to come out there and do a much more detailed investigation for the repair of that site,” he said. “We’re going to get a contractor out there as fast as we can.”

Until a contractor gets out there to investigate it further, Kroning said he does not know exactly how long repairs will take. If all goes well, and the fix involves a pipe replacement, he said it could take anywhere from one to four months.

“We do believe it’s very localized,” he said. “It’s just in that spot.”

Fortunately, residents above the closed off area of Kanapuu Drive have another outlet to enter and exit via Kalanianaole Highway. The affected portion of the drive will remain closed until repairs are made. Halloween trick-or-treaters and the public are advised to remain behind the taped-off area.