The Düsseldorf Opera House has been forced to postpone the opening of its new season and suspend several weeks of performances after structural defects were discovered above the stage.

The problems emerged during a routine safety inspection of the supporting structure at the front of the venue’s stage tower, above the proscenium arch. The structural engineering firm responsible for the inspection declined to clear the stage tower for rehearsals or performances.

Officials said the defects affect sections of the supporting structure at the front of the tower, much of which dates from the period when the opera house reopened after World War II. The load carried by the affected structure must now be redistributed across new beams and columns.

Work is under way to install temporary reinforcements, including specially made steel cables and replacement load-bearing beams.

According to the city government and the opera company, cancellations and postponements are now unavoidable.

The season-opening theater festival scheduled for Sept. 13 has been canceled, along with at least eight performances, including Puccini’s Madama Butterfly. The Oct. 11 premiere of Richard Wagner’s Die Meistersinger von Nürnberg has also been postponed.

Alexandra Stampler-Brown, managing director of Deutsche Oper am Rhein, described the disruption just days before the season opening as a serious blow. Given the structural engineers’ unequivocal assessment, however, she said postponement was the only responsible course of action.

Artistic director Marvin Winter said the company remained determined to stage as much of the planned program as possible despite the difficult circumstances. Its immediate priority is to announce a new premiere date for Die Meistersinger von Nürnberg as soon as possible.

Ticket holders affected by the changes will be contacted individually with details of the cancellations and the options available to them.

The technical problems are the latest setback for Deutsche Oper am Rhein. Only weeks ago, plans for a new opera house—an ambitious project expected to cost billions of euros—were abandoned amid pressure to cut spending. The existing building is now set to undergo renovation, even though city officials had recently said that day-to-day operations were unlikely to be affected.