Updated 5:20 p.m. | Posted 10:43 a.m.
The snow removal system atop U.S. Bank Stadium is leaking and workers will need to remove part of the outside structure next week to fix it, the project's contractor said Friday.
"We identified that there was water leaking out of the parapet walls of the snow gutters at the top of the building," said John Wood, vice president with Mortenson Construction.
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He said the water wasn't actually getting into the stadium interior. But water was penetrating a roof-level liner barrier and getting into an outer wall, where construction crews spotted it leaking out.
Wood estimated the fix will cost $3 million to $4 million. The entire cost of building the stadium tops $1 billion.
It will require a fairly conspicuous repair: workers will have to remove the U.S. Bank Stadium sign and pull off nearly a third of the stadium's outer dark metal cladding to replace the faulty moisture barrier.
Wood said the designers and builders were covering the cost, so it won't be added to the project budget or cost taxpayers or the Vikings for the state-owned NFL stadium.
"It's fortunate that we found the problem during construction, it's going to be fixed during construction and it'll be done by the time the building opens and won't delay that opening," Wood said.
The leak doesn't involve the clear ETFE panels that cover the bowl of the stadium.
Correction (Feb. 19, 2016): A headline and text in an earlier version of this story incorrectly reported that the U.S. Bank Stadium roof was leaking. The leak is in the snow removal system atop the stadium