A forensic engineering firm has been hired to investigate cracks on McKinney ISD's $69.9 million football stadium that is under construction.

"In short, we have greater-than-anticipated cracking," the district's chief financial officer, Jason Bird, told the school board at a briefing Tuesday.

District staff identified the cracks in January and notified contractor Manhattan Construction Group and architectural firm Stantec, Bird said. The affected areas are the home and visitor concourses and the lower bowl wall.

Nelson Forensics — the same firm that studied the cracks in neighboring Allen ISD's $60 million stadium a few years ago — has been retained to identify the source of the problem in McKinney's venue, one of the most expensive high school football facilities in the country.

1 / 3Photos shown during a McKinney ISD board meeting in late May show cracking at the district's $69.9 million football stadium.(McKinney ISD) 2 / 3Cracking, shown during a McKinney ISD board meeting, has been found in the home and visitor concourses and the lower bowl wall of the district's new football stadium.(McKinney ISD) 3 / 3Photos shown during a McKinney ISD board meeting in late May show cracking at the district's $69.9 million football stadium.(Knodel, Jamie)

It's unclear when Nelson Forensics was retained to analyze the cracks, and whether this week was the first time that the school board had heard about the problems. McKinney ISD's spokesman, school board president and superintendent didn't return phone calls Thursday evening.

McKinney ISD was planning to have the 12,000-seat stadium open by the start of this fall's football season. It's uncertain whether the cracking will delay the opening, or when Nelson will report its findings.

"We are aggressively seeking those answers from Nelson," Bird told school board members.

In the case of Allen ISD, which made national headlines when it shut down its pricey Eagle Stadium in 2014, Nelson identified design failings as the main culprit of the structure's problems. District staff spotted cracks on the stadium's horseshoe-shaped concourse around the time the venue opened in 2012 and hired Nelson about a year later as the cracking worsened.

Forensic engineers found flaws in several areas, including the concourse frame, retaining walls, press box support columns, the press box structure, single-story structures and the main scoreboard. Repairs cost at least $10 million, though much of that came about because crews had to remove a lot of the completed structure, an official with architectural firm PBK said then.

PBK and contractor Pogue Construction paid for the repairs at no cost to the district.

In a video of the board briefing, McKinney ISD board president Curtis Rippee suggested that the contractor and architect would be responsible for footing the bill for any repairs.

"To recap, things are progressing," Rippee said. "We have three major concerns: home concourse, visitor concourse and lower bowl wall — the term you actually used. There's an agreement that that's not a McKinney ISD cost issue. Those issues will be resolved either with an existing budget or by one or two providers, and that we're working diligently to find a solution for this issue. ...Correct?"

Bird replied: "That is absolutely correct."

Manhattan and Stantec fielded some questions from board members, but their representatives didn't step up to the microphone, so their answers can't be heard clearly in the video of Tuesday's briefing.

School board member Amy Dankel questioned why the contractor and architectural firm didn't identify the problems first.

"My concern isn't so much that the cracks happened," she said during the board briefing. "I assumed that with a project of this magnitude, things would come up. I am concerned that we were the ones who had to say, 'Hey, what's going on here?' in January, and it still hasn't been resolved."

Representatives with Manhattan and Stantec couldn't be reached for comment Thursday evening.

"The community made a big vote of confidence in the district by allowing us to do this project, and we don't want to disappoint," Rippee said at the school board meeting. "They paid a lot of money for it; we want to make sure to give them a first-class facility."

Rippee told KXAS-TV (NBC5) that the district will issue a statement Friday and declined to comment further.

Voters approved the project in May 2016 as part of a $220 million bond package. McKinney ISD officials acknowledged then that they would be under the microscope after what happened in Allen.

"There are no guarantees in life, but I can guarantee that given what went down just down the road from us, we'll certainly do everything in our power to make sure that doesn't happen here," Superintendent Rick McDaniel said two years ago.

To prepare for the project, district staffers toured stadiums throughout the country, including Allen's.

McKinney ISD spokesman Cody Cunningham told The Dallas Morning News in 2015 that officials chose Stantec because of the district's experience with SHW Group, a design firm that had been recently acquired by Stantec.

SHW had worked on Duncanville ISD's Bill Savage Athletic Complex, Wylie ISD's Pirate Stadium, Fort Bend ISD's Ken Hall Stadium and Beaumont ISD's Carrol A "Butch" Thomas Educational Support Center — all facilities with 10,000 seats or so.

Crews broke ground on the 55-acre site in December 2016. The stadium is just northwest of Central Expressway and State Highway 121 and a few miles from Allen's Eagle Stadium.

The stadium will include the largest true HD video board in a Texas high school stadium, four locker rooms, 2,482 parking spaces and a 6,300-square-foot community events center, the district has said.