The state Department of Transportation is planning to do major work on a retaining wall along Kalanianaole Highway near Makapuu, but the construction will mean more than a year of lane closures and major traffic headaches for residents heading in and out of Waimanalo.

The work was scheduled to begin on Monday, but has been delayed until transportation officials can brief the community on the project and its potential impacts, said Tammy Mori, DOT spokeswoman.

Officials will present the plan to the Waimanalo Neighborhood Board at 7:30 p.m. Monday at the Waimanalo School Library. Mori said DOT will have a better idea then when the project would begin.

The closure will affect a stretch of the highway between the Makapuu Lookout upper parking lot and the entrance to Makapuu Beach Park. The $7.8 million project is expected to be completed in mid-2011, according to the Department of Transportation.

The work will include the construction of a concrete retaining wall, slope stabilization, pavement reconstruction, and cable and conduit installation, DOT said.

During the construction period, a single lane of the highway will be closed from 8:30 a.m. to 3:30 p.m. Mondays through Fridays and an alternating traffic pattern will be used. But all lanes will be closed when night work is done from 8:30 p.m. to 4 a.m. Sundays through Thursdays, the DOT said.

That means residents who normally travel around Makapuu to get to Waimanalo or Kailua from Hawaii Kai will have to deal with the traffic or take the long trip up the Pali Highway. The same applies to residents heading to Hawaii Kai or Downtown Honolulu from Windward Oahu.

Wilson Kekoa Ho, chairman of the Waimanalo Neighborhood Board, said the retaining wall work is needed because there is nothing else that separates the rocky hillside from the highway. He said the community has been trying to get the work done for more than 10 years.

"If the wall goes, there is nothing. Just the mountain," Ho said. "If that thing goes, we're just shut off from the public."

But Ho said he wasn't aware that the road closures would begin so soon and last that long. He added that not only will Waimanalo residents be inconvenienced, but others will be too because he estimated up to 45 percent of the motorists who use the highway don't live in Waimanalo.

"Waimanalo is a bypass between Hawaii Kai and Kailua and that's a lot of the traffic that goes back and forth," Ho said. "So it's going to be a hardship for everyone. Myself, I use that road every day, maybe twice a day, and it's going to be tough especially at night shutting things down."

Motorists are being advised to use caution and observe traffic signs, police officers and traffic control devices during the construction period. The DOT also is advising people to allow for extra time while driving through the area or to use alternate routes.

neighborhood board meeting

When: Monday, 7:30 p.m.

Where: Waimanalo School Library

What: Officials will present plan for work on retaining wall along Kalanianaole Highway.

For more information, contact the Department of Transportation at 587-2160.

Reach Curtis Lum at culum@honoluluadvertiser.com.