Work to eradicate weed shuts down Lake Wilson
| • | State blamed for neglecting situation |
By Walter Wright
Advertiser Staff Writer
WAHIAWA — The state closed Lake Wilson Recreation Area yesterday, saying continuing efforts to remove the invasive weed Salvinia molesta from the lake with heavy equipment make the area unsafe for the public.
Bruce Asato • The Honolulu Advertiser
"It will be a short-term closure with a long-term benefits," said Peter Young, Department of Land and Natural Resources director, whose staff has estimated the weed could be cleared in 28 working days with a full assault by several agencies at up to seven spots on the lake.
A city amphibious excavator scoops a load of the Salvinia weed that has blanketed the surface of Lake Wilson, as workers in small boats prepare to deploy a containment boom around a portion of weed.
The closure announcement came while a floating backhoe continued to nibble away at the weed covering the 300-acre lake, and water and electric crews rushed to repair utilities damaged nearby in clearing a road for the rig.
Half the power was knocked out to the 120 units of the Kemoo By The Lake condominium, where residents had to walk up as many as 10 flights of stairs before electricity was restored to the elevators about 1:30 p.m.
Glenn Higashi, an aquatic biologist with the Department's Division of Aquatic Resources, said backhoe operator Allen Kaaihue plucked out an estimated 112 cubic yards of the plant yesterday in the second day of operations.
That leaves an estimated 74,000 cubic yards to go.
"We're evaluating how this kind of weed removal works on a day-to-day basis," Higashi said.
Officials estimated Kaaihue's 4-by-4-foot bucket scooped up a full acre of the weed Tuesday.
A city driver using a front-end loader painstakingly dumped load after load of the weed into small trash dumpsters on the forks of conventional city garbage collection trucks.
Because the loader bucket was bigger than the dumpster, a slimy mess of the weed repeatedly spilled onto the trucks' windshields and down to the ground in the makeshift system, which the city rushed into place yesterday as it came to the state's aid.
The department's chief engineer, Eric Hirano, this week said the Army Corps of Engineers has recommended that officials set up seven extraction sites. He said different methods of extraction are being considered.
There were many suggestions yesterday from professionals in the business, an inventor and citizen kibitzers on the shore.
Ron Cayetano, a sales and estimating executive with Industrial Waste Cleaning Services, said his firm is prepared to demonstrate a method that will be faster, safer and cheaper than mechanical extraction.
He wouldn't describe what he had in mind, but his business card said the company specializes in a variety of techniques, including wet/dry vacuum pumping, hydroblasting, sandblasting, pressure washing, and truck, equipment and roll-off bin rentals.
Bruce Asato • The Honolulu Advertiser
Inventor Dennis Ruediger, who runs a business on Sand Island, showed up yesterday to see how his idea of somehow lifting the weed out of the water so it can dry before it is moved to shore might make the operation more efficient.
City workers unload gobs of Salvinia molesta into a dumpster for a city rubbish truck to haul away. The 300-acre surface of Lake Wilson in Wahiawa is covered with the stubborn weed.
Joe Mahina, a retired heavy-equipment operator, came to watch the assortment of giant Tonka toys at work, and suggested officials will have to build a temporary causeway into the lake because it will be too difficult to push or pull the weed toward the extraction sites.
There is even a bio-solution afoot: state quarantine officials confirmed yesterday they are examining a suggestion by entomologists that Hawai'i import a Salvinia-eating weevil being used in Texas and some other southern states to fight the plant.
And another potential solution emerged when employees at more than a dozen pet shops that sell aquarium supplies said they don't carry the noxious weed for use in aquariums, because the weed will die in three or four days if it doesn't get sunlight.
The idea of killing the Salvinia by depriving it of sunlight may be a cure worse than the disease, however. "If you put it indoors, within three to five days, it begins to rot," said Rob Lawrence, manager of Koolau Pets, Plants & Ponds at Windward Mall.
People who live near the lake or boat there have said the weed probably was introduced when someone dumped fishpond or aquarium water containing the plant into the lake.
The weed threatens to kill some 500 tons of fish in the lake if oxygen continues to be depleted. A few fish scooped up in the extraction process yesterday flopped around in muddy puddles on shore.
Longtime bass fisherman Kim Seleska says he is certain hundreds of fish have already died, including trophy-sized 8-pound "peacock" bass.
DLNR chief Young said the Lake Wilson Recreation Area will be closed for "an indefinite period" as the state ramps up the extraction effort.
State, city and federal officials also have laid plans to spray weed killer on the plants once sprayers can be mounted from a boat, in an effort to at least keep new growth from overwhelming the harvesting effort.
Advertiser staff writer Zenaida Serrano Espanol contributed to this report. Reach Walter Wright at 525-8054 or wwright@honoluluadvertiser.com.
