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The Honolulu Advertiser
Posted on: Sunday, February 3, 2002

Maui likely to flood again

By Christie Wilson
Neighbor Island Editor

LAHAINA, Maui — A combination of natural and man-made circumstances has conspired to make Lahaina vulnerable to destructive flooding, as last week's storm proved once again.

Public meeting
 •  Feb. 21, 7 p.m.
 •  Lahaina Intermediate School cafeteria, 871 Lahainaluna Road
Since 1879, more than 25 damaging floods have occurred in the historic town, once the capital of the Hawaiian kingdom, a whaling seaport and plantation town and now a tourist mecca. Two of the most recent floods were in 1972, when a rainstorm caused $300,000 damage, and in 1997, when flooding caused an estimated $500,000 damage, largely in the Waine'e Street neighborhood.

Although not nearly as bad as the flooding five years ago, Tuesday's storm inundated a dozen or so properties. Civil Defense officials did not survey the damage, but a rough tally put losses at about $100,000.

It is a scenario likely to recur, one that prevents many residents from obtaining flood insurance.

Maui County has been planning a flood-control program for the slopes above Lahaina for 20 years, but it may be another 10 years before anything is done.

The county missed one opportunity for U.S. Department of Agriculture financing when delays in preparing an environmental report allowed money for the Lahaina Watershed Project to lapse. That money went instead to Hamakua Ditch on the Big Island and it could be five to 10 years before money is available again for the Lahaina project.

At the outset, the cost was $2.8 million. Since then, the price has risen to between $7 million and $10 million.

A new environmental impact statement is being prepared and the public can review the project and offer comments at a meeting at 7 p.m. Feb. 21 in the Lahaina Intermediate School cafeteria.

"When the funds are available, we want to be ready to go," said Wes Nohara of Maui Pineapple Co., who is a director of the West Maui Soil and Water Conservation District.

The Lahaina Watershed Project is a partnership between the conservation district, the county, the U.S. Natural Resources Conservation Service and landowners.

Plans call for four sediment basins and a channel that would run south from the top of Lahainaluna Road across former canefields to an outlet at the shoreline between Launiupoko and Puamana.

"Once there is channelization and storage, it will make a tremendous difference," Nohara said.

Although Lahaina has always lived under the threat of flooding, concerns about a potential disaster became more acute after Amfac's Pioneer Mill stopped sugar production in 1999, leaving thousands of acres of bare, red dirt.

While it was growing sugarcane, the plantation was able to control some of the runoff through a system of reservoirs and ditches. The company also had a work force and heavy equipment at the ready to respond quickly to flood conditions.

Now those controls and resources are gone, and so is the sugarcane that helped hold the soil in place and absorb the rainwater.

Kamehameha Schools, which owns 1,100 acres mauka of Lahaina, leased the land to the sugar company and regained possession last March. The nonprofit trust recognizes the importance of restoring agriculture on the former canefields, said land manager and planner Jeffrey Melrose. Kamehameha has begun leasing parcels to farmers who are growing corn, bananas and other crops, but it's not easy to find tenants, he said, because the old plantation water distribution system is no longer functioning.

Temporary flood-control measures were undertaken in 2000 with $50,000 in federal money, as well as contributions of labor and equipment from landowners Amfac and Maui Pineapple Co. and other companies such as Goodfellow Brothers, which provided heavy equipment in exchange for using some of the soil elsewhere.

An existing drainage basin was dredged to increase capacity, and a 2-mile-long series of earthen terraces were built to capture sheet runoff and direct the water to Kaua'ula Stream, which empties into the ocean in Puamana.

But the intensity of last week's storm — which dumped almost 4 inches of rain over Lahaina in three hours — overwhelmed the temporary system, sending muddy water into yards and homes on Waine'e Street and the surrounding area.

"The terracing and the basin we built worked really well, but there was so much water coming down and so much velocity, there was no way to stop the rush of water," said James "Kimo" Falconer, vice president and general manager of Pioneer Mill Diversified Agriculture, which owns 4,000 acres in West Maui. Falconer also is a director with the soil conservation district.

Earlier winter rains that turned the hills green helped retain some of the runoff.

"If this would have been a year ago, we would have really been sitting in some water," Falconer said.

Although flood victims grumble that not enough is being done to stop of the flow of rain from the mountainside, Falconer pointed out the basin and terrace protected the town from flooding in two earlier storms this season.

"Every single drop of water ended up in Kaua'ula Stream," he said.

Officials inspecting the terraces Friday found at least one break from Tuesday's rain that allowed runoff to wash over the Waine'e Street neighborhood. Nohara said people should realize that the flooding would have been a lot worse without the temporary diversions.

Even when the Lahaina Watershed Project is completed, "no one can promise anyone that their property won't be damaged in a flood," Nohara said.

That's because natural conditions, and some man-made ones, make flooding almost inevitable.

Above Lahainaluna Road is Pa'upa'u, also known as Mount Ball. This geologic feature was formed in a post-erosion eruption, long after deep valleys were carved into the West Maui Mountains that rise steeply above Lahaina town. The Pa'upa'u eruption blocked the outlet from Kaua'ula Valley and redirected the stream, leaving a broad skirt of sloping land with no natural drainage channel.

The result is the sheeting of runoff down into town. Humans contributed to the problem by building Lahaina on a flat, low-

lying strip of land. And, like many old towns, it was built without drainage infrastructure. The Front Street Improvement Project recently installed a storm drain system on the main thoroughfare, but did not address drainage for Waine'e Street and other flood-prone areas.

"The watershed plan will go a long way in helping build up the Lahaina drainage system," said county Public Works Director David Goode.

In the meantime, the county will continue to clear the sand buildup from the concrete drainage outlet that collects the flow from Waine'e and empties into the ocean, and to see that the terraces above town are maintained. The county hopes to be able to connect more storm drains to the Front Street system to provide additional outlets for runoff, but Goode said that will have to compete with other financial priorities for other areas, such as Kaunakakai and Kihei, where drainage work already is under way.

"Drainage infrastructure is going to require funding for many years to come," Goode said.

Many in Lahaina already have lost patience in waiting for a remedy to the flooding problem.

J.J. Elkin, owner of the 505 Front Street retail center, which sustained flooding in 1997 and again last week, said: "We're going to have to pray that we don't get something severe in which we just might lose a life. We don't want to get a reputation for being a dangerous place."