Concerns about migrating birds flying into the new Minnesota Vikings stadium appear to have been quelled in an environmental report issued Thursday that also previewed tensions over who should pay for enhancements at the Downtown East light-rail transit station.

Several agencies, including the Department of Natural Resources and the Metropolitan Council, had asked the Minnesota Sports Facilities Authority to consider the fate of birds migrating along the Mississippi River corridor. The concern was the birds might fatally fly into the glassy new structure or be disoriented by the bright lights.

To help the birds, the authority will turn off the lights overnight at the stadium in the spring and fall and will continue to work with the Audubon Society to ensure bird safety.

Birds were just one topic in the voluminous statement. The authority issued a draft statement earlier this year, then took comments. Some 19 responses came from Hennepin County, Minneapolis, state agencies and private individuals.

"In general, people feel like we're in pretty good shape," said stadium authority chairwoman Michele Kelm-Helgen. The authority will take additional public comment through Aug. 18, then make revisions. A vote on whether to accept the report will come either at the Aug. 23 or the September meeting, Kelm-Helgen said.

Groundbreaking for the $975 million stadium is tentatively scheduled for October. The stadium, on the site of the Metrodome, is expected to be completed in time for the 2016 NFL season. It should be more energy-efficient, particularly in terms of water usage, than the 30-year-old Dome.

Rebuttals to the authority's report suggest a substantial disagreement regarding the Downtown East transit station and who should pay for upgrades to accommodate increased ridership both on game days and from the opening of the Central Corridor line next year.

The Met Council, Minneapolis and Hennepin County said the authority's final environmental report needs to detail a plan and a means to pay for changes to the transit station that ensure pleasant game-day experience for LRT passengers with easy queuing and loading.

The authority's response, however, said the Downtown East station is operated by Metropolitan Transit, a division of the Met Council. The response said the authority isn't responsible for and doesn't plan any "physical changes" at the Downtown East station. However, the project will expand the plaza to the west of the stadium, enhancing the pedestrian experience, the report said.

Hennepin County Administrator David Hough submitted the most pointed comments, saying the county is "deeply concerned" that the authority's report "does not adequately address" changes coming to the Downtown East station in the next decade. He emphasized the importance of a complete infrastructure plan for the new stadium.

"Failure to get this right will inevitably result in unacceptable congestion, interference with all modes of transportation and significant public safety risk," he wrote.

The Associated Press contributed to this report. Rochelle Olson • 612-673-1747 @rochelleolson