3 Big Island dams found unsafe

Inspectors advise the owners to breach the structures if they are not going to be used

Emergency visual dam inspections carried out by the U.S. Army Corps of Engineers found three Big Island reservoirs that need to be refurbished or destroyed.

The owners of Hawi No. 5, Lalakea and E-13 reservoirs need to decide whether they are going to make the investment needed to bring them up to current standards, the state's adjutant general, Maj. Gen. Robert G.F. Lee, said yesterday.

"And the recommendations right there say if you don't, you should abandon the reservoir, do an emergency breach so it doesn't collect water, and we render the reservoir harmless," Lee said.

Reservoirs and their dams throughout the state were ordered inspected after the Ka Loko reservoir broke on Kauai in March, killing seven people.

"We wanted the inspectors to let us know if we had any reservoirs anywhere in the state that was in a condition of imminent failure like Ka Loko. And the answer was no," Lee said.

"The Big Island is probably, from a comparison standpoint, a little better off than the rest of the state," he said. "I've still got to take a look at Maui yet, but as far as the condition of the reservoirs, (the Big Island reservoirs are) pretty good."

In all, 13 dams were inspected on the Big Island. A detailed report on each dam was given to the owner so any recommended corrective actions could be taken.

"I'm happy to report the public reservoirs -- we have a couple owned by the state of Hawaii Department of Agriculture and a couple that are owned by the Big Island county from the water department -- they're generally overall very good," Lee said.

All 13 of the Big Island earthen dams inspected for immediate hazards in April were judged to be safe at that time.

But lax maintenance has allowed overgrowth of brush, grass and trees that may hide structural flaws, according to the reports released yesterday and available online at the state Department of Land and Natural Resources Web site.

Seven of the Big Island's dams are classified as high-hazard, based on the potential loss of life and property downstream if the dams were breached.

But that classification does not reflect on the stability of the dam structures.

Kamehameha Schools owns two of the three earthen dams -- Lalakea and E-13 reservoirs.

The report on the Lalakea Reservoir said corrective actions required to maintain the safety of the embankment would be extensive, and abandonment was recommended to preserve the safety of downstream inhabitants or visitors.

If the E-13 Reservoir is no longer needed, the corps recommended the dam be breached or the embankment removed to natural ground level.

As for Hawi No. 5, the corps said, "This dam is not in use and should be breached by the owner if it will not be used."

The U.S. Army Corps of Engineers, federal National Resources Conservation Service and state Department of Agriculture assisted the state DLNR in emergency visual inspections of dams in April.