Inouye addresses threat of flooding in Kane'ohe
By Eloise Aguiar
Advertiser Windward O'ahu Writer
KANE'OHE — Sen. Daniel Inouye has thrown the weight of his office behind solving a flooding threat at Kapunahala Stream, adding to a state and city effort to address the issue first raised by area residents in the 1980s.
The stream that runs through Castle Hills and Kahelelani subdivisions in Kane'ohe has been a concern to residents for years as it slowly eats away the stream banks, coming closer to homes and threatening to wipe out property as it did in 1996 when erosion from one storm forced a family to abandon their home.
"It's just getting worse and worse," said Kahelelani resident Richard Nakamoto. He said extra water flowing into his subdivision since the 1980s has undermined homes and they are beginning to settle and crack.
Inouye first heard about the problem earlier this year when an aide attended a Kane'ohe Neighborhood Board meeting where the issue was discussed. Inouye said he would request federal money for a city proposal to build a bypass drainage system that could cost approximately $6 million. The city would have to come up with 20 percent matching money.
"I am committed to doing my part to acquire federal highway funds," Inouye said in a letter to the Kane'ohe Neighborhood Board.
The bypass drainage system was proposed years ago but never had money. Now the idea apparently has been resurrected, and the state Department of Transportation has proposed a complementary solution.
But the two didn't always work together.
The DOT has jurisdiction over the upper level of the stream and the city has jurisdiction over the lower level, and for a long time each blamed the other on the issue. In recent months, both have committed to working together to solve the problem.
Residents say the problem was created when Castle Hills subdivision was built in the 1980s. The land was filled, causing rain runoff that once flowed toward Likelike Highway to flow to Kahelelani subdivision.
At the same time, the state built a 12-foot-by-20-foot concrete culvert at the entrance to Castle Hills that collected runoff and channeled it into the stream that flows next to Kahelelani homes and to a smaller city culvert. During heavy rain the city culvert — 4 feet by 6 feet — isn't able to handle the flow from the larger culvert, causing the stream to back up and flood neighboring properties.
Earlier this year, Rod Haraga, state director of the Department of Transportation, agreed to explore solutions.
After three meetings with residents and the Kane'ohe Neighborhood Board, the state has proposed to line the stream with walls of gabions, wire-mesh containers filled with rocks, said DOT spokes-man Scott Ishikawa.
The state would create a wall 10 feet to 15 feet high that's about 350 feet in length from Po'okela Street to the culvert, Ishikawa said. The gabion wall would address flood and erosion concerns, he said.
Residents wanted a concrete culvert, Nakamoto said. But Ishikawa said it would be subject to soil movement and could crack.
"The gabion design would be able to adjust to any soil movement," Ishikawa said. "We feel this is the best option because they're more natural, more aesthetically pleasing."
If the city and state agree on the plan, the state would request money next year and construction could begin late next year, Ishikawa said, adding that the state wants the city to take over jurisdiction of the stream.
Nakamoto said the community also wants the city to build a bypass system to handle heavy downpours. The money Inouye seeks would help pay for the city project, Nakamoto said.
