The U.S. Army Corps of Engineers and the City and County of Honolulu have scheduled public meetings before the release of a new project plan to reduce risk of catastrophic flooding in the Ala Wai watershed.
An earlier proposal for an Ala Wai flood risk management project met with widespread community opposition in 2019 and was canceled due to the withdrawal of $345 million in federal funding.
The original plan included building a 4-foot-high wall around the Ala Wai Canal and placing six large debris catchment and retention basins in the upper sections of the watershed streams.
On Wednesday evening, Henry Kruse, paddling coach for Roosevelt High School, said the original plan raised an immediate red flag for the six outrigger canoe racing clubs that have been based for generations on the banks of the canal in Ala Wai Park near the McCully Bridge.
With a wall stopping and collecting the water mauka of the canal, as envisioned, “there would be no way to exit our canoes out of the park,” said Kruse, who noted the Ala Wai clubs had to tow their craft to race sites outside of the Waikiki area. Kruse said he raised the issue at a public meeting and learned canoe exits weren’t part of the plan.
“The wall would be built within the park, the flood zone would be the whole Ala Wai Park, the golf course and all the way up to ‘Iolani School, and they didn’t design a way out of the Ala Wai,” he said.
In 2020, the Army Corps issued an engineering draft report for a new plan, which has since been abandoned, that eliminated the much-criticized upper watershed basins while retaining three larger basins at Hausten Ditch, Kanewai Field and the Ala Wai Golf Course, and kept the 4-foot walls around the canal while proposing more walls inland at Makiki and elsewhere.
At a virtual public forum on Jan. 20, the city and the Army Corps unveiled a new communications tool that has been added to the updated project website at honolulu.gov/AlaWai.
The new tool, a spreadsheet titled the “Management Measure Tracker,” is intended to provide more opportunities for public engagement following complaints from the community about not being heard during the original planning process, Eric Merriam, a planner for the Army Corps, said in the January forum, the first public meeting since two workshops in November.
“A lot of public input they felt (wasn’t) necessarily considered in previous meetings we’re going to incorporate in the spreadsheet,” Merriam said.
Facilitator Tyson Vaughan, a sociologist with the Army Corps, said lack of trust and needing more opportunities to participate in the planning were among the top issues raised by community members in November.
“We’ll be adding more workshops, particularly during the early phase, when input has the most potential to shape the plan,” he said.
According to an “Ala Wai Flood Risk Management General Reevaluation Study” on the project website, flooding in the watershed, where Makiki, Manoa and Palolo streams drain into the Ala Wai Canal, threatens 200,000 residents, as well as schools and businesses. Estimated damage from a major flood could cost $1.14 billion.
“This is a must-do project,” Alex Kozlov, director of the city’s Department of Design and Construction, said in the virtual forum, stressing the potential damage of an overflowing Ala Wai Canal flooding “the economic engine of Waikiki.”
“Just this past December there was that Kona low that produced heavy rainfall,” said Cindy Acpal, project manager for the Army Corps, “(when) five boys needed to get rescued from Palolo Stream, and just a couple of valleys over in Nuuanu, another five people needed to get rescued.”
Acpal noted approximately 85 residential properties had been affected by the storm, which was also associated with two landslides and the closure of the H-1 Freeway at the Punahou overpass and Vineyard Boulevard, while models showed “this watershed has a 20% chance every year to see a storm of this magnitude.”
The new flood risk model had been updated with the most recent data, incorporating sea-level rise and other effects of climate change, Merriam said.
He and Vaughn urged the public to visit the website, noting that in order to best be heard, people should submit written comments and risk abatement ideas via email or the website comment forum. The current crowdsource reporting tool will be taken down at the end of January.
They said the tracker spreadsheet, last updated Jan. 19, had 188 ideas and that they will look at every one before honing down the alternatives after the March and April workshops.
Another series of workshops is planned for summer, with a draft report to be issued in the fall, followed by a public comment period, with the final report to be completed in early 2023.
About 75 people participated in the virtual forum, Tim Sakahara, city spokesman, said in an email.
Questions, invited 45 minutes into the one-hour meeting, included whether repaving of mauka roads with permeable surfaces was being considered. The answer was yes.
A person asking about the city’s capacity for stream cleaning and maintenance was told that 90% of streams on Oahu are privately owned, and the city cleans 10% of the remaining 10% every year.
“This last big storm, it was so packed with rubbish by the McCully Bridge you could almost walk across the Ala Wai,” Kruse said. “They dredge the canal but they never dredge upriver.”
For more information, visit honolulu.gov/AlaWai.
Correction: An earlier version of this story did not specify which Ala Wai flood risk management plan Henry Kruse was referencing. He was referring to plans that were cancelled, not the new plan, which is in a preliminary, idea-collecting phase.