Officials: Vikings stadium bird-safe glass could cost $60M

MINNEAPOLIS - Adding bird-safe glass to the Minnesota Vikings' new stadium could add as much as $60 million in extra costs and delay construction by six months, the chairwoman of the Minnesota Sports Facilities Authority said Friday.

Chairwoman Michele Kelm-Helgen gave the estimate in response to complaints that the clear glass planned for the $1 billion downtown Minneapolis stadium would pose a threat to migratory birds, Minnesota Public Radio News reported.

''If you look at Mortenson (Construction), their subcontractors, all of our consultants and staff that are working on this project -and you're extending the whole project from two to six months - you're looking at costs that would be anywhere from $25 (million) to $60 million and potentially higher,'' Kelm-Helgen said.

Kelm-Helgen said Viracon, the stadium's Owatonna-based glass maker, has said changing the glass order to substitute etched or ''fritted'' glass would take as much as 23 extra weeks, possibly keep the Vikings in TCF Bank Stadium at the University of Minnesota for an additional season, and divert other events. She said that could affect the rent the Vikings would pay to the stadium authority.

''So that $10 million might conceivably not come in,'' Kelm-Helgen said.

Kelm-Helgen repeated that stadium construction would proceed as planned. The Vikings are set to play in their new stadium with an inaugural preseason in mid-August 2016. The new stadium will host the 2018 Super Bowl.

She also offered more detail on the plans to test a number of film coatings produced by Maplewood-based 3M Co. that might make the glass safer for birds. The University of Minnesota will help monitor the tests. But the authority has made no firm commitment to use the films.

Bird advocates have been citing a smaller figure, about $1 million, as the added cost for ''fritted'' glass.

But stadium officials say that doesn't account for potential lost revenue, such as Vikings game rent, or possible legal action by contractors seeking compensation for indirect costs of lost business due to schedule changes.

''I'm not sure I believe that,'' said Lisa Venable of Minnesota Citizens for the Protection of Migratory Birds. She said she'd like to see proof.