A three-year Hawaii County plan to fully reopen Waipio Valley Road by mitigating its safety hazards was met with little opposition Wednesday.
The county road was closed in February to all except Waipio Valley residents after an emergency proclamation by Mayor Mitch Roth, following a geotechnical evaluation that found that the road’s conditions were too unsafe to allow public use, citing elevated risks of rockfalls.
In September, following an April lawsuit by a community group, the county permitted Big Island residents and some commercial tour operators to travel the road with four-wheel-drive vehicles, but no work to improve the safety of the road has been made yet.
On Wednesday, however, the Department of Public Works unveiled plans for a multiphase project to mitigate the dangers of the road. Dozens of area residents packed into the Honokaa Gymnasium to hear those plans, presented by Public Works Director Steve Pause and a pair of consultants from Honolulu geotechnical firm Haley and Aldrich.
Pause said the plans are to improve the road as quickly as possible and with minimal impact to the environment. To that effect, the project would be segmented into three phases, the first of which could begin as early as next spring and would take four or five weeks to complete.
Haley and Aldrich geologist Chris Eddy said Phase 1 is the simplest and safest to complete, because it involves the removal of various hazards along the uppermost portions of the road — from immediately past the Ranger Station to just beyond the switchback, a little over 700 feet.
The hazards to be removed would be trees, vegetation, root mats, minor rocks and “scallops,” rocks along the cliff face that have been gradually undermined until they protrude.
Pause said planning work on Phase 1 is still ongoing, and that Phase 2 and 3 will require substantially more planning.
“We want to be able to get the smaller work done while we plan for the bigger work,” Eddy said.
Phase 2, Eddy explained, will similarly remove loose debris and scallops from the cliff face while also installing metal mesh along the cliff to contain rockfalls. The phase is divided into four subphases focusing on different sections of the road.
The final phase will install more rockfall fences higher upslope above middle sections of the road. Eddy said that because of the difficulty of accessing the higher slopes, this phase is expected to take longer than Phase 2, but could be combined with that phase to save on costs.
Concurrently with the second two phases, the county also will make improvements to the road itself.
DPW’s Acting Engineering Division Chief Alan Thompson said those improvements will include repaving, repainting, replacing guardrails and signage and more.
Thompson added that, starting next month, the county will do some maintenance downslope from the road, including trimming trees and vegetation to improve visibility. That work is expected to be completed after four weeks, with only two days of work each week, but is technically considered separate from the primary road safety project.
Pause said he hopes the final phases will be completed within three years.
“As far as our road projects go, I don’t think it’s the biggest one we have,” Pause said, guessing that road rehabilitation projects at Kalanianaole Avenue and in Waikoloa may be more expensive. “But it’s probably the most difficult one right now.”
A previous estimate for the project set the cost at about $6 million per phase, but Pause said Wednesday that the project will almost certainly cost more than that. A rough estimate included with Haley and Aldrich’s design report in September estimated the cost of installing rockfall meshes in Phases 2 and 3 at $2.7 million, but noted that it does not include ancillary permitting or construction costs.
The meeting, though well-attended, was fairly sedate throughout. However, the presenters did not address any questions relating to how the county will handle access to the road. DPW spokeswoman Sherise Kana‘e-Kane said those questions will be addressed at a future public meeting.
“I’m glad they’re finally working on making the road safer,” said Ahualoa resident Laura Coverly. “I would like to see some way to control the number of cars that go down there. … Tourists probably shouldn’t be allowed to drive down there.”
Email Michael Brestovansky at mbrestovansky@hawaiitribune-herald.com.