Round Top Drive above Honolulu likely will remain closed to through traffic until the end of this year as more repairs are completed, city officials said.

The scenic road that winds around Tantalus from Makiki has been closed since heavy rain and flooding washed out or weakened some sections more than a year ago.

After trimming heavy vegetation, repair crews recently discovered that a 120-foot-long wall beside the road was deteriorating and must be strengthened, officials said.

The extra work is expected to cost $1 million, bringing the project's total cost to $5.5 million.

The closed portion is just before the first "hairpin turn" mauka of the intersection of Round Top Drive and 'Ainalani Place.

The closure has inconvenienced many residents who have had to take the long way around the mountain, via Tantalus Drive, to reach their homes.

Emergency vehicles also have been delayed.

"It's a problem for the residents," said John Steelquist, chairman of the Makiki/Lower Punchbowl/Tantalus Neighborhood Board. "It takes longer to get where we're going and it's a safety issue."

Police and ambulances were forced to take the winding Tantalus Drive to reach a scenic lookout where three people were shot and killed a year ago.

Police said their response time was delayed several minutes because of the detour. Adam Mau-Goffredo, who was arrested in connection with the case, is awaiting trial.

Access to the scenic Pu'u 'Ualaka'a State Park, and its spectacular views over Downtown Honolulu, has also been curtailed. Visitors to the park must access it via Tantalus Drive, though Round Top Drive is shorter.

The project's completion date has been pushed back several times after inspections and surveys found additional work was needed.

"The work they're doing has got to be done, but it's a little too bad they didn't know it six months ago," Steelquist said. "They might have saved some time with more careful planning, but it has to be done."

City spokesman Bill Brennan said officials want to fix problems that become apparent before opening the road, so that another closure won't be necessary soon.