Makapuu rock work Rockfall prevention work on the mountain above Kalanianaole Highway at Makapuu will extend one to two weeks past the original completion date of Nov. 27, according to state officials.
extended
1 lane of the roadway will be open
during the netting installationBy Genevieve A. Suzuki
gsuzuki@starbulletin.comThe extra time is needed to install netting and fencing material on the hillside. But the state plans to open one lane of the highway during the installation.
The highway has been closed from 8:30 a.m. to 4:30 p.m. every day since the project started on Nov. 6.
No work will be done over the Thanksgiving Day weekend. When work resumes on Dec. 2, crews will use a helicopter to deliver the 2,000-pound netting material that will be laid over the mountain from Makapuu Lookout to Makapuu Beach Park, a state Department of Transportation official said.
One lane of the highway will remain closed in case anything is dropped while the scalers stitch the pieces of the netting material together, DOT director Brian Minaai said in e-mail.
"The likelihood of loose material falling is unlikely if we place the netting immediately after the scaling is completed," Minaai said.
The state is still in the middle of the scaling and blasting phase of the project, which Minaai said was expected to take 10 to 12 days.
The state is using dynamite and controlled blasting to remove seven rocky overhangs.
Controlled blasts are low charges strategically placed along a fractured line on the rocky overhangs to produce a smooth sloped surface. A series of holes, 2 inches in diameter and spaced approximately 20 inches apart, are drilled along the line at the back of each overhang and in front of several of the larger overhangs.
To break the overhang into smaller pieces, the explosives located at the front of the outcrop will be detonated milliseconds later than those located at the back.
Between blasts, eight scalers rappel from the top of the mountain to dislodge loose rocks and debris. The state's contractor, Royal Contracting Co. Ltd., hired scalers from California who have done similar work along the U.S. West Coast, said DOT officials.
"What they are doing is dangerous, which is why the work cannot be done at night," Minaai said.
A ground crew of five men then remove rocks from the roadway with front-end loaders, a sweeper and dump trucks, according to Minaai.
Once the blasting and the scaling is completed, the final step is to install the chain-link fencing and netting over the slope.
The 6-foot-high chain-link fencing, made of 9-gauge zinc-coated steel and covered with a heavy-duty PVC coating, will be installed at the top of the slope, approximately 30 to 40 feet from the edge.
The netting consists of a triple twisted hexagonal mesh of 12-gauge zinc-coated steel wire. The 2,000-pound material comes in 13-by-300-foot-long rolls.
The state began preparing for construction Nov. 6 by placing 6-foot by 10-foot steel panels along Kalanianaole Highway to protect it from falling boulders. Fallen rocks are estimated to be no more than 3 feet in diameter.
Construction on the Makapuu hillside was moved up from February after a rockslide closed the highway for 13 hours on Oct. 15.
