U.S. Army Corps of Engineers (USACE) is partnering with the County of Hawaii Department of Public Works for a Waiakea and Palai streams flood reduction project.
The Waiakea-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 Waiakea Stream watershed and the Palai Stream watershed.
“The proposed improvements will reduce the risks to life, structure, property, and public infrastructure from periodic flooding in certain locations within the vicinity of Waiakea and Palai Streams,” said Honolulu District Project Manager Michael Neaverth, Jr.
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 Waiakea-Palai Streams in Hilo, Hawaii 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 Hawaii, anticipated Spring/Summer 2023.
The study area encompasses the Waiakea Stream watershed and the Palai Stream watershed near the town of Hilo, Hawaii, located on the eastern coast of the island of Hawaii. A severe flood that occurred on Nov. 2, 2000, caused significant damage to several residential areas on the island of Hawaii, including the Waiakea Stream area of Hilo. Homes near Kawailani Street Bridge, Kupulau Road, and several areas in Waiakea Uka were damaged due to flood waters exceeding stream capacities. Another severe flood event 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 Waiakea 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.
Water overflows the Waiakea and Palai streams due to limited capacity to transport flood waters located on the eastern coast of the island of Hawaii. During significant rainfall events the overtopping of these streams results in flooding downstream areas. The Waiakea-Palai flood reduction project will address the risk to life, structures, property, and public infrastructure from significant rainfall and periodic flooding in the locations within the vicinity of the Waiakea and Palai Streams. (Photo courtesy of U.S. Army Corps of Engineers, Honolulu District)