The Wailupe Stream Flood Risk Management study is a new start General Investigation Feasibility Study authorized under Section 209 of the Rivers & Harbors Act of 1962. This stream is in the southeastern portion of the island of Oahu, within the Aina Haina community. The non-federal sponsor for this study is the City and County of Honolulu. In alignment with the City’s letter of request for USACE assistance, the study will investigate potential measures to reduce flood risk along Wailupe Stream.

Several historical floods have occurred along Wailupe Stream since the Aina Haina community was developed. Damages from the floods of March 5-6, 1958, and December 16, 1987, were significant. Since these events, the stream has come close to overtopping on several occasions, including a storm event in March 2006, and most recently with the storm events of April 13, 2018, and December 6, 2021. The storm event on April 13, 2018, produced torrential rainfall and severe flooding along Wailupe Stream that caused erosion to the stream banks, from the boulder basin to Hind Drive, and adversely impacted most of the properties along the stream. Letters of request from the City and County of Honolulu for assistance to complete a Feasibility Study have been submitted for consideration every year since 2020.

The study’s feasibility cost sharing agreement was executed on 26 September 2024. The study is in its early stages with the project delivery team beginning efforts to develop the study’s scope, schedule, and budget.