Big Island dams get favorable report
|||50 percent of O'ahu dams vulnerable|
|||Flaws found at all Kaua'i dams|
By Kevin Dayton
Advertiser Big Island Bureau
By Kevin Dayton
HILO, Hawai'i — Most of the 13 Big Island dams that underwent emergency inspections by state and federal authorities in April need maintenance, but none pose an immediate threat to the public, according to reports released yesterday.
The visual inspections turned up only minor fixes or additional monitoring needed at eight of the dams, including one owned by Parker Ranch that has already been breached.
Reservoirs and their dams statewide were ordered inspected after the Kaloko dam broke on Kaua'i 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 Kaloko. And the answer was no," said Maj. Gen. Robert G.F. Lee, the state's adjutant general.
"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 Hawai'i 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.
Not that all the dams were trouble-free. Inspectors rated portions of the Keaiwa Reservoir in Ka'u as unsatisfactory, noting vegetation growing on the downstream slope and crest, and downstream of the spillway. The report also questioned whether the two spillways are large enough to protect the dam under flood conditions, and noted cracks in the structure that were caused by an earthquake years ago.
John Cross, land manager for the Edmund C. Olson Trust II, said the reservoir is kept at 2 million gallons, far below its capacity of nearly 14 million gallons, and a system is in place to drain water before it ever nears the level of the cracks.
Water from the reservoir is used to irrigate macadamia nut, coffee and some truck crops including taro, Cross said. It is the only reservoir of significant size in the district, Cross said.
He said the trust has been maintaining the reservoir and plans to remove vegetation, but said the facility poses no threat to anyone because there are no homes or other structures in the immediate area.
Inspectors also found the Hawi 3 Reservoir to be generally in fair to poor condition, with vegetation growing on the crest and slopes, and questioned whether that reservoir spillway is large enough to prevent water from topping the dam in a flood.
Inspectors also rated the spillways on both Lalakea and the "E-13 Reservoir" in Hamakua as unsatisfactory, and noted that trees are blocking the Lalakea spillway approach. The report also questioned whether the Lalakea spillway is large enough to function properly under flood conditions.
Kekoa Paulsen, spokesman for Kamehameha Schools, said the trust has been reviewing the nine dams it owns statewide to determine what repairs or maintenance is required, or whether some should be removed.
That includes Lalakea, Hawi 3 and E-13, the three dams Kamehameha Schools owns on the Big Island. Hawi 3 is the only one of the three on the Big Island now being used, Paulsen said.
"We're looking at all three of them with the options being to either restore and bring them up to full standard, or to remove them," Paulsen said. "We haven't made final decisions on any of them yet."
In the meantime, "In our evaluation, there's not enough water in any of them to pose an immediate danger," he said.
The emergency inspections by the state and U.S. Army Corps of Engineers were prompted by the failure of the Koloko dam on Kaua'i on March 14.The Associated Press contributed to this report.
Reach Kevin Dayton at email@example.com.