The U.S. Army Corps of Engineers (USACE) is partnering with the County of Hawaiʻi Department of Public Works for a Waiākea and Palai streams flood reduction project.

The Waiākea-Palai project will include construction of detention basins, a diversion channel, levees, and floodwalls to reduce flood risks to structures, property, and critical infrastructure in the Waiākea Stream watershed and the Palai Stream watershed.

The integrated Feasibility Report, Environmental Assessment (FR/EA) and Finding of No Significant Impact (FONSI) for the CAP Section 205 Flood Risk Management project at Waiākea-Palai Streams in Hilo was approved by USACE Pacific Division on Sept. 29.

The project will move into the Design and Implementation Phase, which will be initiated by executing a Project Partner Agreement between USACE and the County of Hawaiʻi, anticipated Spring/Summer 2023.

The study area encompasses the Waiākea Stream watershed and the Palai Stream near Hilo.  A severe flood that occurred on Nov. 2, 2000, caused significant damage to several Big Island residential areas  including the Waiākea Stream area of Hilo, homes near Kawailani Street Bridge, Kupulau Road, and several areas in Waiākea Uka.  Another severe flood occurred on Feb. 2, 2008, when the stream overflowed its banks, and 150 homes were damaged. A state of emergency was declared for Hilo, Puna, and Kau areas on Feb. 3, 2008, when 18 inches of rain fell in the Waiakea Uka area within 24 hours.

This project will address the risks to life, structures, property, and public infrastructure from periodic flooding in certain locations within the vicinity of Waiākea and Palai Streams. The proposed structures will temporarily store floodwaters and effectively route flood waters downstream preventing overflow.

For more information, contact the USACE Honolulu District Public Affairs Office at (808) 835-4003 or at cepoh-pa@usace.army.mil.

 

Photo Credit: Hawaiʻi County Department of Public Works