The Springbrook Nature Center in Fridley, widely known for its large bird population and annual bird counts, soon will get an avian-inspired upgrade.

An 8,000-square-foot glass-walled addition will be made to Springbrook's interpretive center, featuring a V-shaped roof mimicking the form of wings and inspired by the 127-acre preserve's abundance of birds and its popular bird-banding program. The upgrade is part of a $7.6 million overhaul, a long-pursued undertaking that is finally underway after the state approved $5 million for the project last year.

Last week, project leaders presented initial plans to community members at an open house, receiving a generally favorable reaction. They highlighted the building's sustainability and multipurpose use — renovations that project leaders say will help support the center in coming years.

"[We're] trying to use the building as a model of sustainable design," said Paul Anderson, one of the project's architects.

The green roof will collect rainwater and bring it to a rain-garden water feature at the building's entrance, which eventually will filter into the wetland. The building also will have a geothermal heating and cooling system, Anderson said.

The building will have multiple rooms, including one with three partitions and seating for 250. It can be used for a number of smaller events, or for larger occasions like weddings, Anderson said.

"It's designed to accommodate as many different audiences that use it, and it is designed to accommodate all of those simultaneously," Anderson said. "We want to maintain this strong indoor-outdoor relationship, so that you're always aware of where you are."

Planners will adjust the initial renderings and designs, taking into consideration community feedback before bids are sought in March. Malcolm Mitchell, chairman of the Springbrook Nature Center Foundation Board, said the building addition is likely to be completed by June 2016.

Mitchell said more than $2 million still needs to be raised before the entire project can be completed, but construction on the addition is likely to begin in May.

"As we begin this process of construction now, that helps us raise money," Mitchell said. "It shows things are happening."

The current interpretive center is a 5,000-square-foot stucco-faced structure tucked into the side of a hill. The addition will more than double that space.

Mitchell said the board is working to raise the remaining money and has been in the "quiet phase" of fundraising since November. This will continue through May, when the board will take the fundraising to the greater community.

"We're building the base before we go to the community; we'll then kind of finalize what the goal is for the whole thing when we go public in May," Mitchell said.

If the rest of the money is raised, he said, in a few years a picnic pavilion and amphitheater will be added to the site.

Rep. Carolyn Laine, DFL-Columbia Heights, said the upgrades are long overdue. Laine drafted the first request to the state for funds more than 10 years ago, when the preserve was still in her district.

"We've been waiting and waiting and hoping it happened before Springbrook was actually too worn down or unneeded," she said.

She said the state didn't originally think the property was of "regional significance" — a major criterion for projects to get state bonding money — but over the years they realized the crowd that the area brings in.

Anna Pribula, a 46-year Fridley resident and frequent visitor to the preserve, was one of those at last week's open house. She said the expansion is much needed.

"It's a real gem for the whole Twin Cities," she said.

Taylor Nachtigal is a University of Minnesota journalism student on assignment with the Star Tribune.