Not just any dome will do for the National Sports Center.

The amateur sports campus in Blaine, touted as the largest in the world, wants to go sky-high with a new 110-foot dome to house indoor turf sports.

If approved, the proposed 120,000-square-foot structure would be one of the tallest in Blaine — to the chagrin of some city officials, who are pushing for the height to be scaled back to 75 feet.

City Council members expect to weigh the project's approval on Oct. 18.

"The 110-foot-high dome would be out of place, given the very open nature of the site," associate city planner Lori Johnson said Sept. 11 at the Planning Commission meeting. "You [would] see it from all of the major roadways in Blaine."

But Sports Center officials say that standing out is a key factor behind the design.

"One of the unique things about the National Sports Center has always been its scale," Executive Director Todd Johnson said at the commission meeting. "We looked for different ways to make this truly unique."

Height, he said, offers that distinction, given that there's "only so wide you can build a bubble like this because of snow load."

The 110-foot inflatable dome would be the largest of its kind in North America, beating out a 95-foot dome in Texas, according to Sports Center officials. They say the height would easily accommodate sports like baseball and softball, which can damage shorter structures.

"A higher roof would open it up to more customers," said Barclay Kruse, spokesman for the National Sports Center.

But city staffers are recommending capping the height of the structure at 75 feet and increasing the setback on 105th Avenue from 48 feet to 60 feet.

"We're not comfortable with that 48-foot setback," Lori Johnson said at the meeting. "If the building is 50 feet tall, we would require a setback of 50 feet. It's like a fall zone."

The cost is estimated at more than $5.5 million, with plans to pay off the construction debt with revenue from future programs and rentals in the facility, Kruse said. "We are not asking to access public money," he said.

The dome, planned for the north side of 105th Avenue near Davenport Street, would replace two soccer fields and some parking. The dome's fabric membrane would be supported by air.

The project is part of the recently completed campus master plan as the sports complex, which opened in 1990, looks to the future. Sports Center officials say that one of their key needs is more indoor turf space for sports like soccer, lacrosse, baseball, softball and golf.

Kruse said the Blaine Soccer Club would be a "prime user" of the facility. "Most of the users are going to be people who live relatively close by," he said.

Staffers want the City Council to wait to issue building permits for the new facility until other site issues are resolved at the Sports Center, including relocating a maintenance facility from 105th Avenue and closing a sand and dirt mining operation on the campus.

If approved, the Sports Center hopes to finish the dome by next July, in time for the annual Schwan's USA Cup youth soccer tournament and the new PGA Tour tournament planned for TPC Twin Cities in Blaine.

"We will make this work," Kruse said. "If we have to build it lower, it's absolutely not our preference … but we're not going to deep-six the whole project over this issue."

Hannah Covington • 612-673-4751