Airport Retaining Wall Failing, Public Foots The Bill

BROOMFIELD, Colo. (CBS4) - A massive airport retaining wall built just a few years ago is already failing and it's costing the public a bundle of money. The airport manager says it could not have been predicted.

The retaining wall is on the north end of the Rocky Mountain Metropolitan Airport in Broomfield.

"There's generally concern that, 'Is the wall crumbling? Is it falling down?' " Airport Manager Ken Maenpa said.

The 70-foot-high wall, which supports a new taxiway, has a massive crack in it. It's big enough to fit an arm in. Dirt is pouring out and the instability shows in jagged cracks throughout.

"Since we discovered, and got confirmation that the wall was indeed moving, it's impacted a lot of people, including myself, because we've all been working together on solutions to stop it from moving," Maenpa said.

At one point airport administrators say the wall was moving as much as three inches every week. They had to temporarily stop using a road on top of the wall. They've poured 12,000 cubic yards of dirt at the base of the wall to help stabilize things. The project is now encroaching on state Highway 128.

So far the airport has had to spend about $250,000 in public money to buttress the problem wall, but a permanent fix will cost a whole lot more.

Authorities say they suddenly discovered this year water was flowing under the wall -- hundred gallons a day -- eating away at the foundation.

"A term that I would use is 'unforeseen condition.' When you go through and you're using good engineering practices when you're designing something and doing everything that you should do and something like water appears out of nowhere -- that's whose fault, if you want to start talking about fault, that's the best that we could probably come up with right now," Maenpa said.

They say the huge dirt berm has stopped the wall from moving -- for now -- and they don't think it's in danger of falling down. But airport administrators are searching around for a permanent fix.

They say they are looking at all options up to tearing the whole wall down and starting over.