2/25/22 #kihei This morning Civil Beat published this article concerning South Maui’s flooding situation.
The aftermath of a powerful Kona Low that pummeled Hawaii in early December continues to reverberate, particularly among Kihei residents on Maui’s south shore.
The storm unleashed heavy rainfall and strong winds across the islands prompting Gov. David Ige to declare a state of emergency. President Joe Biden approved a disaster declaration for Hawaii this month, ordering federal aid be made available to help communities recover from the storm damage, flooding and landslides of Dec. 5-10.
In Kihei, flash floods forced gulches to overflow with water, mud and debris, causing major damage. Kihei water quality specialist Robin Knox describes the fierce storm as a “game-changer.”
Before December, many people expressed concern about the impact of flooding on Kihei’s ocean environment and the tourism industry. But the impacts have multiplied, and people are grappling with how to protect their homes, livelihoods and their health, she said.
“The economy is now threatened, and human health is now threatened because of this environmental degradation,” she said.
Knox is poised to release a study that examines how wetlands protection and restoration might help. She’s joined in her efforts to help avert future flooding disasters by an ecological designer who wrote a study in 2020, funded by Maui County, on environmentally friendly methods to mitigate some of Kihei’s flooding challenges. Some Kihei residents are hoping that the county will release the study and ultimately follow its recommendations — especially after the community largely rejected the county’s 2016 drainage plan for the area.
‘She Literally Had To Be Dug Out’
The Maui Meadows subdivision in South Kihei, an eclectic neighborhood of some 640 homes, was especially hard hit by the Kona Low, with floodwaters and mud barreling through homes and yards, and washing vehicles away.
Debra Greene, president of the Maui Meadows Neighborhood Association, said the velocity of the water, boulders and debris coming down the mountain was frightening.
“As it goes downhill it gains speed and picks up whatever is in the path. That can be gravel, it can be household goods. It can be lawn chairs and furniture or whatever. There were all sorts of things that got carried down,” Greene said. “People’s belongings are probably in Tahiti by now.”
One of Greene’s neighbors got trapped inside by several feet of mud that blocked her doors, she said.
“She literally had to be dug out,” Greene said.
Painting contractor Carlo Alioto had 3 feet of sludge flow through a cottage on his property, his garage and his main house. He’s had to replace appliances, drywall, rugs and his 2021 Subaru.
“All the electronics are under the seat,” Alioto said. “The car was totaled.”
Aliota was outside when the flooding started but realized he needed to get inside the house quickly for protection. The water and mud were pushing so hard against the doors that he ended up climbing through a window to get inside.
“I was scrambling for my life,” Aliota said. “It was unbelievable.”
The storm caused Aliota and his wife thousands of dollars in damage. A neighbor set up a Go Fund Me page for Aliota, who is undergoing treatment for bladder cancer. More than $9,000 was quickly raised, he said, praising his neighbors for their generosity and help with repairs.
Damaged property isn’t the only thing residents are concerned about. Several cite the potential health impacts from the contaminated stormwater and mud.
After heavy storms, overflow from cesspools, sewers, and manholes can mix with runoff and become a toxic brew. Pesticides, animal feces and carcasses, chemicals, pet waste, and all manner of pathogens can also be found in storm runoff, according to health officials.
Mike Moran, president of the Kihei Community Association, said it’s not unusual to find skulls and bones from ranches mauka on the beaches of Kihei.
When David Everson bought his property in Maui Meadows, he had no idea the neighborhood was subject to flooding. Since buying the house, the retail marketing executive has learned a lot more about Maui Meadows and what lies uphill.
“With all the deforestation up there in the cattle area, there is no natural soil protection. So, when you do have what I would call these flash floods or heavy rains, it runs straight down the mountain. In prior years, way back in the day, there were these beautiful sandalwood trees up there,” said Everson. “But when you remove all the trees and the infrastructure of soil, now water just goes anywhere.”
Barrier walls that homeowners tend to erect to keep floodwaters off their property often end up compounding the problem for others nearby. The walls can divert water, mud and debris into other people’s yards, Everson said, including his own.
‘A Formula for Disaster’
Some in Maui Meadows along with members of the Kihei Community Association are frustrated that more isn’t being done to fix the area’s drainage problems, especially when more frequent intense storms are likely to occur as the planet warms.
Knox, the water quality specialist, is among those trying to help. She spoke at the association’s Jan. 18 virtual meeting as an invited guest. Knox works as a project manager for Save the Wetlands Hui. With a grant from the county, the hui is mapping and monitoring hydrological flows in the area, identifying critical wetlands in need of repair, and conducting ecological restoration work, among other tasks. The hui is expected to release a 267-page technical report soon.
One of the major reasons Kihei and its nearshore waters suffer serious flooding is because less than 50% of the area’s original wetlands are left, Knox said. By design, wetlands have the capacity to absorb floodwaters and settle sediment. But because so much of Kihei’s wetlands were paved over, the land’s capacity to absorb rainfall is not what it used to be.
With climate change fueling more powerful storms like December’s, combined with wetlands’ loss and degraded watersheds, “it’s a formula for disaster,” Knox said. Unless action is taken, the community can expect a lot more “mudfloods,” as she describes them.
The solutions must involve wetlands restoration and protection, better grazing management, protection of riverbanks, stabilization of unpaved roads, community outreach and education, and other measures, she said.
“We can’t just fix this by protecting wetlands at the bottom, or building flood walls at the bottom,” Knox said. “We really need to look mauka.”
Ecological designer Amanda Cording has some ideas about that. Maui County hired her to craft nature-based methods to improve flood control in Kihei’s Kulanihakoi and Waipuilani river drainages.
Cording, with EcoSolutions, came on the scene after the county released a Kihei drainage master plan in November 2016. The Kihei Community Association and others objected to the plan because it envisioned a substantial amount of “hardening,” or the construction of concrete diversion channels and basins, Moran said.
County officials didn’t go forward with the plan because of community objections, Moran said. But they hired Cording to look at alternative approaches.
During the Jan. 18 meeting of the Kihei Community Association, Cording, who has a doctorate in ecological design, offered highlights of her 49-page report. It offers an array of environmentally friendly strategies that could help control flooding and improve drainage.
Cording finished her report in September 2020. The county has yet to release it, Moran and others said. It’s unclear what’s holding it up.
The Cost Of Improved Drainage
Frustrated by what she saw as foot-dragging, Knox managed to obtain a draft of the report last November after threatening legal action. The draft suggests strategies like the construction of vegetated retaining walls, replacing undersized culverts and dune stabilization to help control flooding, as well as channel stabilization techniques to reduce the transport of sediments.
The estimated cost of improving drainage in the Kulanihakoi watershed was around $6.4 million while the Waipuilani watershed costs could be anywhere from $4.7 million to $12 million, depending on the strategies chosen in Cording’s plan.
Under the county’s 2016 master plan, the estimated cost of addressing Kulanihakoi flooding was $57 million, which included the concrete water diversion from Waipuilani gully to Kulanihakoi. Waipuilani improvements in the 2016 plan were estimated at $16.8 million.
One of the most effective steps the county could take in the short term would be to replace inadequate culverts along South Kihei Road, Cording said.
There’s still some “back and forth” with the county over technical comments the engineering division submitted, Cording said. She’s looking forward to hearing what the community has to say once the county officially releases the report and requests public comments.
On a broader scale, things are happening at the state and county levels to support climate mitigation and adaptation, said Erin Derrington, a shoreline planner for Maui County. Efforts include reducing the risks of flooding through emergency management planning and critical infrastructure programs, she said.
Taking an ahupuaa or watershed approach that looks at challenges and opportunities from ridge to reef is a priority, and the planning department considers all development in light of these long-term plans, Derrington said.
Civil Beat’s coverage of Maui County is supported in part by a grant from the Nuestro Futuro Foundation. Civil Beat’s coverage of climate change is supported by the Environmental Funders Group of the Hawaii Community Foundation, Marisla Fund of the Hawaii Community Foundation and the Frost Family Foundation.