The U.S. Army Corps of Engineers is proposing three flood control projects for the Waiakea and Palai streams in Hilo.
The projects involve construction of water detention areas, including one at the Hilo Municipal Golf Course, plus a levee near Kupulau Road and a diversion near Ainalako Road.
Jeffrey Herzog, Army Corps project manager, said the flood control measures would allow excess water to be collected in detention areas and released at a slower rate to prevent homes from being inundated.
The Army Corps and Hawaii County met with residents near the project sites, and a community meeting is scheduled for 6-8 p.m. Tuesday in the golf course’s multipurpose room.
Herzog said the draft environmental assessment will be released the same day.
Preliminary cost estimates for the projects is $12 million, with 65% of that covered by federal funds. The county’s share would be about $4.2 million.
Construction is expected to start in 2021 and would take two years.
Herzog said the Army Corps is careful not to increase flood hazards for anyone else as a result of the projects.
The Ainalako diversion would send excess capacity from Palai Stream into a detention area, which would drain into Four Mile Creek. He said the creek can handle the additional flow, but residents in that area are asked to attend the meeting to provide feedback.
The planning effort is a result of severe flooding caused in 2000.
The projects could result in changes to flood maps that could reduce flood insurance costs and requirements for property owners.
Email Tom Callis at email@example.com.