Dam work – cold, clear conditions ideal for dam inspection

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Fort Dodge, IA — People might say that Ryan Bell picked a really strange time to take a dip in the Des Moines River.

With mounds of snow lining the riverbanks and the water temperature right at the freezing mark, Thursday seemed like a bad day to go swimming. The cold, clear water was perfect, however, for getting a look at what’s below the surface.

So Bell, a licensed structural engineer and commercial diver, donned about 100 pounds of gear and dropped into the ice-clogged river to check out the Fort Dodge Hydroelectric Dam.

He spent several hours Wednesday and Thursday underwater near the dam. On Thursday morning, he slid down the dam’s spillway in a rope harness to reach part of the structure’s downstream side.

Bell’s job was to collect information on the condition of the dam that city officials will use when they eventually decide what to do with it. About two hours worth of video was recorded with a camera mounted on his diving helmet. He also took some photos with an underwater camera.

Engineers have yet to study the video and photos, but Bell said his preliminary impression is that the 93-year-old dam is in good condition.

”Everything’s in good shape, sitting on top of a solid foundation of rock,” he said.

He did find some holes in the gates that allow water to pass through the dam.

Bell and the crew he works with are employees of Stanley Consultants Inc., a nationwide engineering firm hired by the City Council on Monday to do an inspection of the dam. The firm will be paid up to $20,000 for the work.

The team of Bell; Todd Brooks, another diver; and Ben Voss, who handles the video equipment from a trailer on the shore; is based in West Palm Beach, Fla. Those three are aided by Hank Mann, a civil engineer with 40 years of diving experience who works from Stanley’s Muscatine office.

The diving crew was working in the Midwest when the City Council acted, so it arrived in Fort Dodge Tuesday. By 7:15 a.m. Wednesday, the team members were on the 2-foot-thick ice covering the river.

City Parks, Recreation and Forestry Department workers used a chain saw to cut triangular openings in the ice. Mann said a triangle is the best shape for such an opening because divers can grab the edges to pull themselves out of the water.

Bell entered those openings wearing long underwear, two pairs of socks, a diving garment called a dry suit, coveralls, a 30-pound helmet, an air tank and swim flippers.

Once underwater, he could see up to 10 feet away.

”The visibility was actually pretty good,” he said.

To preserve that visibility, he moved carefully to avoid stirring up the silt on the river bottom.

The diving operation drew one spectator Thursday morning. Gary Carr, who has fished near the dam since 1959, stood on a hillside in Loomis Park as the divers and city crews worked.

”This has never been done to my knowledge,” he said.

When their work in Fort Dodge was done Thursday morning the divers packed up for the return to Florida. There, Bell will dive in the Everglades, where alligators – rather than ice – will be his prime worry.

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