The Twin Cities is in the midst of a sports dome building boom, with more than a dozen of the structures — largely publicly funded — sprinkled across the metro area, and four new ones in the works for 2020.

In a northern climate, domes are "almost a price of admission for relevancy in the sports world these days," said Todd Johnson, executive director of the National Sports Center in Blaine. Many sports groups and city officials say they're a valuable amenity, providing space for local athletes and drawing new families to a community.

But the domes also can pose financial risks, and their growing number has critics wondering just how many domes one metro area can support — and whether taxpayers should continue to fund them.

"This is not a proper function of government … [but] any opposition would be perceived as anti-sport, anti-kids," said Annette Meeks, CEO of the Freedom Foundation of Minnesota. Taxes, she said, should be used to "benefit the greatest amount of people, not just where the loudest hockey boosters are."

From Plymouth to Rosemount, domes began springing up in the metro area in the late 1990s and continued into the mid-2000s. The west metro now is considered saturated with them, while south metro communities are catching up and northern suburbs are trying to fill the gap. Their rapid growth reflects the growing trend of amateur and professional sports being played year-round, whether it's baseball, soccer or lacrosse. Gregg Nelson, vice president of Minneapolis-based Yeadon Domes, which constructs domes, said he believes there are more sports domes per capita in the Twin Cities than anywhere else.

The National Sports Center is one of three places in the metro area that will see a new dome in the coming year. The others are Brooklyn Park and Lakeville, where turf fields will be constructed at both high schools by fall and the domes will likely come later.

But Savage's experience this fall may offer the first hint that the metro is reaching a tipping point with domes. A reduction in team rentals at Savage's city-funded dome forced officials to budget an extra $100,000 next year to support operations, raising the suburb's annual dome subsidy to $350,000.

"What we didn't anticipate is that domes would become as popular as they are and that other communities would be building them all over," said Brad Larson, Savage's city administrator.

Not a moneymaker

While sports domes aren't cheap, they're seen as a less expensive alternative to building a recreation center entirely out of bricks and mortar. Residents in many communities have made pitches for their own sports domes over the years. The fundamental challenge remains how to fund them and then keep them going.

Most domes are financed with taxpayer dollars through cities, school districts or some combination. That's the case in Brooklyn Park, where the city and the Osseo Area Schools are sharing the costs of building a $5.5 million dome. It will be primarily used for school athletics and gym classes, but the city will rent out space on evenings and weekends.

The double dose of domes in fast-growing Lakeville is being funded through a partnership, with $6 million from a recently approved school district levy going toward turf fields and a private group paying $4.5 million for the actual dome structures.

Johnson said loans will finance construction of the $4.8 million sports dome at the National Sports Center. He called building domes "an extremely skinny business."

"I assume that anyone going into these ventures understands what the bottom line is on them," he said, adding: "I think people can break even."

It can be difficult for sports domes to generate revenue for several reasons: competition, weather issues like snow buildup and storms, and the inefficiency of their design, Johnson said. He noted that big pieces of plastic or fabric filled with hot air are hard to keep warm in winter.

Many communities accept the financial reality of domes. Savage Mayor Janet Williams said the dome hosts not just sports but community events like movie nights and the annual Halloween party. By day, it offers a place for adults to walk and children to play.

"I am committed to this because I believe it's an amenity for our city," Williams said. "It's hard to put a [dollar] number on it."

The athletic center for the Eastern Carver County Schools opened in Chaska in 2017 to hold middle-school gym classes. School sports teams have priority, followed by community teams. The dome features batting cages, a full-size track and three fields.

DeeDee Kahring, the school district's finance and operations director, said they didn't expect to make money on the facility or even recover costs.

"I think that's one thing that's different for us," she said. "Our main focus is students."

Though domes aren't moneymakers, several cities have found strategies to keep them running while planning for future replacements.

Plymouth Creek Center Fieldhouse manager Chris Fleck said a fund established in 1999, the year the city-owned structure was built, had amassed $800,000 to replace it in 2017. Now Plymouth, which has another dome at Wayzata Middle School, is saving up to replace its turf.

There's a similar arrangement in West St. Paul, where a $7 million dome built in 2012 is supported by $230,000 to $250,000 annually in property taxes. The money goes toward future replacement costs, said City Manager Ryan Schroeder. "Everything we do, we do because a private entity can't really do it … because they'd go broke," he said.

When West St. Paul's dome is paid off in 2034, it will theoretically begin making money, he said.

Sleepless nights

Dome managers say they get little sleep during the winter months, when snow and wind pose the greatest threat. "You don't want a Metrodome collapse," Fleck said. "Every year it seems like a dome goes down."

Maple Grove's dome fell four years ago due to wind storms. But the Vadnais Sports Center in Vadnais Heights may offer the greatest cautionary tale. That dome, which officials said was never intended to cost taxpayers money, deflated just a month after it opened in 2010.

Problems persisted. Revenue estimates proved to be too high, and the nonprofit that owned it started missing payments. The city used $6 million in bonding and legal fees to prop it up until Ramsey County bought it in 2014 for less than half of what it cost to build.

During an April 2018 blizzard, it collapsed again. Now Ramsey County is giving up on the dome and replacing it with a truss roof. The Vadnais Heights situation was a "train wreck," said Nelson. But he said it's an isolated case; last winter, he said, no domes collapsed anywhere around the metro area despite all the snow. He said dome demand remains strong in the Twin Cities.

"I don't know where the saturation point is, but we haven't reached it," he said.