The new home for the Minnesota Vikings will be taller and bigger than the Metrodome and will have a sloped roof and possibly, sliding walls, windows or doors that open to the downtown Minneapolis skyline, according to a public document released Monday.

Those details, spelled out in a nearly 400-page draft Environmental Impact Statement made public by the Minnesota Sports Facilities Authority, provide the first glimpse of a project that is expected to replace the Metrodome by the 2016 NFL season.

The authority, which is working with the Vikings to develop the $975 million multipurpose stadium, plans to unveil the architect’s preliminary design at a special meeting May 13 at the Guthrie Theater.

The draft impact statement, however, provides some clues to the project’s closely guarded design. The stadium facade could be made up of a combination of metal panels, Kasota limestone and curtain walls that appear transparent or translucent when lit. It will feature four entrances, but 75 percent of the fans are expected to enter and exit through the west plaza, which faces downtown. That entrance could feature sliding and pivoting doors.

The stadium’s roof, which will be nearly 100 feet taller than the Metrodome’s highest point (195 feet), could be permanent or retractable, and include a combination of hard deck and fabric, which would allow sunlight into the building much like the Beijing Water Cube made famous in the 2008 Olympics.

All totaled, the 65,500-seat stadium, which can seat as many as 73,000 fans for special events such as a Super Bowl, will be nearly twice the size of the Metrodome, encompassing up to 1.7 million square feet. It would be “a bold, iconic, geometric structure with long sloping, angular facets that are primarily directed toward the downtown Minneapolis skyline,” the draft said.

Michele Kelm-Helgen, chairwoman of the authority, said Monday that many of the features detailed in the plan have yet to be decided as the team and authority try to nail down what can be built within the stadium’s budget.

She said that most will be firmed up by the time stadium architects unveil the design in two weeks. The draft document “has a lot of options in it,” she said. “I wouldn’t assume all those things are in or out or settled on.”

Kelm-Helgen said all the options for a retractable roof and retractable walls or windows also “are still in play.”

The draft also includes two options for a plaza outside the stadium. One would run for north-south, along Chicago Avenue between 3rd Street South and 5th Street South. The other would run east to west from Chicago Avenue to 5th Avenue between 4th Street South and 5th Street South and include the block where the Star Tribune is headquartered.

“This would involve the demolition of the existing Star Tribune building,” the document said.

The configuration of the plaza depends on the outcome of negotiations between Minneapolis-based developer Ryan Cos. and the Star Tribune, which owns five blocks near the stadium, much of it surface parking lots, and Ryan’s ability to secure a development prospect. Ryan said late last year it was contemplating “multiple development scenarios” for the Star Tribune land.

Earlier this month, Minneapolis Mayor R.T. Rybak called for creation of a park called “Armory Yard” to be located near the historic Armory along 5th Street South. The space could include a skate park, rope courses, soccer and lacrosse fields, a croquet pitch, dog park and other “four season features,” Rybak said.

Last week, Lester Bagley, vice president of stadium development for the Vikings, described negotiations for acquiring land surrounding the stadium site as “fluid.”

Star Tribune CEO Michael Klingensmith declined to comment on either the Ryan or Viking negotiations. Rick Collins, vice president of development for Ryan, could not be reached for comment Monday.