Divers to Spend a Month Underwater Fixing Century-Old Cheesman Dam

Yet another critical job made possible by SCUBA.

A daring operation is under way, deep under water at Cheesman Reservoir.

Divers are attempting to replace the dam's aging gates which allow water to pass through the structure.

The current gates were installed in 1895, when the dam was built.

The plan for divers to replace the gates was thought to be better than the alternative, which would have required draining the lake.

That’s something that hasn’t been done in more than a century.

Draining the lake could have also jeopardized Denver’s water supply and taken months to refill.

...

Divers are installing new stainless steel gates which allow water to pass through the dam. Two teams of two divers working 12 hour shifts are in a pressurized chamber for 28 days straight.

"They’re in a chamber which I guess you could equate to a big propane tank," said Mark Hintz, dive superintendent with Global Diving and Salvage Inc.

The divers are supported on deck by a 20 person crew.

"They have a cook. Good food. You burn a lot of calories in there," said Hintz.

For the entire month the divers live in a chamber and breathe 90 percent helium and 10 percent oxygen, which makes them sound a little like Donald Duck.

"They have a motorcycle looking helmet, or space-like helmet. It’s probably an odd scene if you could see it from the outside," said Hintz.

If all goes well, the dam will be fine for another 100 years. Big pressure -- both literally and figuratively -- on the divers to restore the dam’s aging gates.

"The storage here is about 80,000 acre feet," said Martin.

"Everyone’s got to be safe or they’re not on the job," said Hintz.

The crews "pressed down" on Monday night.

Continue reading...