State details plans to shore up Honoapiilani Highway
WEST MAUI – What is the state’s strategy on upholding Honoapiilani Highway along the eight-mile scenic stretch between Puamana and the Pali?
With three major operations on the books to shore up threatened sections, it appears the state is on a patch and preserve mode.
The Lahaina News interviewed Dan Meisenzahl, chief of communications for the Hawaii Department of Transportation (HDOT), about these fortification measures.
Along a 4,000-foot strip between Ukumehame and Papalaua parks, coastal reinforcement is currently underway.
The scope of work along the southern end of the byway was detailed by Meisenzahl.
“We’re widening the road mauka, and we’ll actually move the lane that is closest to the ocean to the lane that is closest to the mountain. That way, when we start work on the coastal area, we don’t have to shut down any lanes. It will have a minimal impact to the traffic,” the communications director said.
The work was granted under the Governor’s Emergency Proclamation after the March 2011 tsunami.
“The tsunami severely undermined this section of highway, which we constantly monitor to avoid closure of the highway, which is the only access in and out of Lahaina.
“Although the proclamation did waive the SMA (Maui County Special Management Area) permit,” Meisenzahl continued, “we did send a letter to the Maui County Planning Office to let them know what we were planning. We also had to get permits from Department of Health and the Army Corps of Engineers.”
Coastal armoring is the proposed fix.
“The existing revetment on the Ukumehame (Beach) Park end will be repaired and extended to protect the highway. The retaining wall along the remainder of the project reach will be built with a rock slope on the lower section on the seaward side to prevent erosion and undermining of the retaining wall,” Meisenzahl confirmed.
“The retaining wall is designed to retain the soils and the highway loads in a very limited right-of-way area. The primary reinforcing for the wall is stainless steel rebars and the secondary reinforcing is fiber-reinforced-plastic (FRP) bars. The lower portion of the retaining wall will be protected with a rock slope,” he added.
The project’s budget is $7 million.
In Olowalu, buttressing with boulders has been approved along a makai 900-foot section of Honoapiilani Highway between Launiupoko Point and Hekili Point.
“The boulder fill will provide protection to the shoreline and highway from seasonal high surf and the infrequent waves from passing hurricanes and will replace the cobble shoreline with a boulder slope,” the SMA application reads.
The need for the $2 million request was loud and clear in the application.
“In recent years, concrete jersey barriers have been placed along the seaward edge of the highway pavement to mitigate wave over-topping and to prevent closure of the highway during high surf conditions. This and other mitigation measures have been determined to be inadequate in addressing the present imminent collapse of the roadway pavement along this 900 feet section of Honoapiilani Highway.”
According to Meisenzahl, the HDOT is predicting the commencement of construction along the cobble shoreline in 2013 with a timeframe of nine months to complete.
Work at the Launiupoko end of the thoroughfare is forecasted to begin in 2014 at an approximate expense of $2.9 million.
“The scope of work for Launiupoko is to construct approximately 600 feet of rock revetments and install guardrails along Honoapiilani Highway,” Meisenzahl explained.
“The project is necessary,” the state chief of communications continued, “because the roadway is being undermined due to storm damage and erosion.
“Erosion is a big problem across the state and is having an impact on many state roads, including Kamehameha Highway on the Windward Side of Oahu, Lumahai on Kauai and, of course, Highway 30,” Meisenzahl added.
The potential price tag of the three fixes at the beginning, middle and end of the byway is almost $12 million.
However, should other expenses more difficult to determine be factored into the equation?
With 590 feet of beach loss experienced with the installation of the previous revetment at Ukumehame as determined by a University of Hawaii study, how much would it cost to replace the sand and this valuable community, recreational resource?
Or should the highway be relocated mauka with a potential outlay ranging from $450 to $750 million, including the cost of land.
“The relocation of Highway 30 is very far from becoming a reality,” Meisenzahl advised, but it is on the drawing board.
“HDOT is just beginning the planning phase. After that is complete, it would go to the design phase and then an EIS would have to be completed, which normally takes two to three years. HDOT would also have to secure funding from federal highways, which would be no easy feat considering the possible price tag,” Meisenzahl added.
Alternatives are available.
Tara Owns works for the University of Hawaii Sea Grant College Program.
The coastal processes and hazards specialist and consultant to the County of Maui offered several solutions, along with a warning.
“We should be relocating portions of the highway, even if only to a small degree, along the erosion hotspots. That’s a remedy that could have been applied at either Olowalu or Ukumehame, but it hasn’t been,” she said.
“And, by the way, even if the entire highway were eventually relocated, there is no reason why the abandoned land couldn’t be designated as open space. Instead, the shoreline is being permanently hardened, which will change its natural function, beauty and usability – access to and along – forever. Right now, this approach should concern the community.
“This is one of the few places in Hawaii where there is undeveloped space to allow for partial or total relocation. In other places, the option would not even exist; so I am continually troubled that our community is opting for the tradeoff when it probably is not necessary,” she said.
The only route the scientists frown upon is turning a blind eye to the situation.
“That is the only artery into and out of West Maui, and it is highly vulnerable to sea level rise. Coastal erosion is taking away the road. Sea level is rising now; and it’s going to accelerate in the future,” U.H. Geologist Dr. Chip Fletcher warned.
“It’s a very vulnerable stretch of highway; and to ignore and not make plans for either raising it or moving it is a serious mistake.”