A multimillion-dollar plan to protect Waikiki and nearby communities from a flooding disaster appears to be coming into focus as the Army Corps of Engineers announced it will present its “prospective plan” at a virtual meeting April 24.
Officials said the plan is an early version of the “tentatively selected plan” that will be described in a draft Ala Wai Canal Flood Risk Management General Re- evaluation report scheduled to be unveiled in June, with public meetings to follow.
A final Ala Wai report is expected to be ready by the end of 2023 or early 2024, according to the Army Corps’ timeline.
The 5:30 p.m. virtual meeting, being held in partnership with the city, is expected to feature an overview of the project, a description of government- mandated environmental review requirements and a presentation of the planning process, including development, evaluation and comparison of the final array of alternatives.
Those alternatives, as of December, included three potential action plans. One focuses on water storage, predominately detention basins to hold stormwater. Another is aimed primarily at water conveyance, featuring a variety of channels and flood walls.
The third is a combination of the two, featuring both detention and water conveyance projects, including flood walls around the Ala Wai Canal, at Kanaha stream, Woodlawn Bridge and Koali Road, and detention basins at Manoa Valley and Makiki district parks and Ala Wai Golf Course.
In the end, the final plan is likely to feature a combination of projects that aim to help Waikiki and the Ala Wai watershed, including communities along Makiki, Manoa and Palolo streams, withstand a storm size that would only occur every 20 to 50 years, officials said.
Officials said they are preparing a sneak preview of the prospective plan that is to be presented April 24; it will be available online after Monday at the project’s website, honolulu.gov/alawai.
Officials said the online video will be an abridged version of the virtual meeting and is being prepared in order to maximize time for public input at the meeting. The public is being encouraged to watch it before the April 24 virtual meeting.
“The intent is to provide a resource for those newer to the study to review in place of downloading and viewing hours of previous recordings,” said Amy Bugala, Army Corps of Engineers Honolulu District public affairs specialist.
But the video also will include a description of the “prospective plan” and talk about the work and analysis Army Corps engineers have accomplished since the last round of public meetings in December.
As part of the Ala Wai planning process, the Army Corps in February announced in the Federal Register that it would be writing an environmental impact statement for the project rather than a less comprehensive environmental assessment document.
After the agency and the city failed to inform the public about the change, a deadline for comment was extended from March 24 to May 8.
The effort represents the latest attempt to deal with a potential problem that was identified years ago: The Ala Wai Canal is unable to hold enough water to protect Waikiki and nearby areas from flooding from a massive storm.
With climate change generating sea-level rise and increasing the potential for powerful storms, the threat of a flooding disaster looms even larger for the 200,000 residents living along the Makiki, Manoa and Palolo streams and the Ala Wai Canal.
The Ala Wai Flood Risk Management project dates back to 1999, but it wasn’t authorized and funded for design and construction until 2018. The effort hit the skids in 2020, however, after estimated costs had nearly doubled to $651 million amid community dissension about the flood walls planned around the Ala Wai.
In a new agreement with the city, the federal government agreed to pay up to $3 million for a general evaluation study to come up with a new plan that aims to draw on previous knowledge and balance risk and cost.