The former architect of the new Farmington High School made mistakes that have affected everything from the building's security to its drainage, according to the school district.

That allegation is contained in a countersuit that the Farmington district served Monday on its former architect, DLR Group, which sued the district in November, claiming nonpayment of fees. The dispute, under way in Dakota County District Court, comes less than a year before students are scheduled to start classes in the $100 million high school and just weeks after the district fired DLR.

Among the district's complaints:

•The architect designed the building in such a way that parts of the third floor cannot be "locked down" in an emergency, a flaw that also affects security on the school's other floors.

•Poor drainage has led to ponding west of the building.

•Many design elements did not meet code standards for handicapped access, fire safety, sanitation and more.

Fixing the flaws has led to extra costs.

The district is working on a solution to the lock-down problem that may involve adding extra doors, said Rosalyn Pautzke, the district's administrative services director. "Safety and security are enormous concerns, and we aren't going to compromise that," she said.

DLR managing principal Griff Davenport declined to comment on the accusations Monday, saying the firm had not had a chance to review the district's claims. But it's typical for large projects to generate a certain number of building code problems and oversights that are fixed during construction, he has said.

The district and DLR have been at odds for months over who should pay for more than $1 million of those fixes. Changes were needed on everything from handrails to basketball backboards.

The building has bigger flaws, too, including a media center floor that's not level and concrete flooring in restrooms and science labs that will need expensive maintenance, the district said.

DLR, which also served as construction manager for part of the project, also failed to produce reliable timetables that workmen could follow, and the project was "consistently over budget" under the firm's supervision, the district claims. The district paid $344,000 to settle a claim brought by a steel erector because of a dispute with DLR over work on the school. In addition, the district took issue with DLR's remodeling plans for the old high school and Middle School East, which are wrapped up in the move to the new high school.

The school district has paid its architect $5.3 million since 2004, and DLR has sent bills for about $600,000, the district said. Now, the district wants all of that money back, plus attorney's fees and more than $50,000 in damages.

In December the district replaced DLR with Wolfgram/Knutson of Eagan. It hired Pope Associates of St. Paul to take over remodeling of the other schools.

Construction of the high school is on schedule and on budget, Pautzke said. The high school is more than 80 percent complete, and remodeling work at the other schools should start at the end of the school year.

Sarah Lemagie • 952-882-9016