These duck boats are delivering medical supplies and rescuing Harvey victims

This duck boat is out rescuing victims from Hurricane Harvey

Hurricane Harvey's record-breaking flooding in Houston, Tex. this week, left nearly 300,000 people without power, many of whom expect to remain in the dark for weeks, and led 35,000 to take refuge in shelters.

After four feet of rain, many residents faced difficulty getting out of their home. Kayakers plucked treading neighbors out of the water. A midwife rode an inflatable swan to work so she could deliver a baby. And on Monday, Austin Duck Adventures brought two of their Amphibious Hydra-Terra commercial tour buses, which ride on land and water, to Galveston to join the effort.

Source: Kirk Haney

"We helped deliver medical supplies," Kirk Haney, 39, a volunteer and friend of the company's co-owner, Paul Mahler, tells CNBC Make It. The University of Texas Medical Branch hospital was inaccessible to an 18-wheeler.

Then, on Wednesday, they made their way to the Briarforest area and found local police who gave them the addresses of people who still needed to be rescued.

"Of course you can't see the road or anything," says Haney. "It was a heavily wooded neighborhood." Local residents, wading through the water beside the bus, guided their way.

They picked up six people, Haney says, including an elderly couple that had apparently been stuck in their home for three days. Unlike other boats that had tried to get them out, their amphibious vehicle had a ladder.

Source: Victor Dearmond

"They were able to come out of their front door," says Haney, "but they would've had to wade or swim through a quarter mile of water."

The size of the 40-foot tour bus made it optimal for supply delivery, but hard to maneuver in the neighborhood. "Even in normal conditions it's challenging to drive in a residential street." says Haney, "You have to look out for trees and branches and power lines."

It's a shame no one in the area had access to the Amphibious Responder, a search and rescue vehicle designed for situations like a hurricane, John Giljam, the president Cool Amphibious Manufacturers International, tells CNBC Make It. The only manufactured one is in Bangkok, Thailand.

Source: John Giljam

"It's smaller and gets into places," he says, "but it can have firefighting capability, winches, extrication equipment." It's also powered by twin engines and armored so it can remove other cars stuck in its way.

Despite the difficulty with navigating the tour bus, Haney and the others from Austin Duck Adventures were still able to help. "You know, we're doing great," he says, inspired by everyone he saw in Houston joining the effort.

"There are tons and tons of people there." he says, "The biggest challenge is how do you help and where do you help." As of Friday, they still have a vehicle and a driver down in Houston. "Law enforcement has our information," he says.

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