Following the failure of the Kaloko dam on Kaua’i in which seven people died in March, an extensive survey of the Hawaii island chain’s hydro power facilities has revealed a significant number of maintenance issues.
Inspections have already been completed on Kaua’i and most recently O’ahu’s 16 dams and reservoirs. Surveys of Maui and the Big Island of Hawai’i are to follow.
On O’ahu a number of the facilities are overgrown with vegetation, preventing detailed inspection, and it least one dam has a major erosion gully across the crest.
Generally found to be in fair or acceptable condition, none of the dams are in imminent danger of failure, however problems associated with a lack of maintenance including overgrown stream beds, erosion, seepage, damaged spillways and vegetation growing on embankments could leave at least half of the dams and reservoirs on O’ahu vulnerable to flooding, the reports say.
Furthermore, while the reservoirs themselves were free of problems, upstream and downstream slope areas were cluttered with heavy vegetation that could be uprooted during heavy rains or high winds and cause damage to dam embankments.
The Oahu Dam Inspection Reports, a cooperative effort between the Department of Land and Natural Resources and the US Army Corps of Engineers, can be found at www.hawaii.gov/dlnr/reports/dam-inspections/ or by clicking the weblink below.