Organizers were already under scrutiny after 17 children were hospitalised and dozens required medical attention during the final two days of the song and dance extravaganza which involved thousands of young people from across the country and beyond.
The exact cause of the collapses is still not known, but accounts of some parents and participants have said children were simply pushed too hard for too long until they became exhausted - a situation not likely to have been helped by being packed together more tightly than recommended.
Now, an LTV report aired Thursday reveals civil engineers advised the festival organizers than no more than 6,000 people should be on stage at one time. In fact around 12,500 were on stage throughout, though festival organizers insist their decision was normal practice, in line with previous events at the iconic Mezaparks Stage.
Standard worldwide practise would be to allow each participant not less than half a meter of space, said Riga Technical University Assistant Professor Aigars Ūdris who was among those giving the advice based on various factors including the weight of participants, the overall load, distribution dynamics and more.
"The singers actually were forced to stand leaning [against each other], so the compression rate was quite high, which means it does not comply with these risk assessment criteria," said Ūdris.
Accordingly, the place reserved for each participant was not half a meter but around 35 centimeters.
However, festival organizers say they are confident that because smaller, lighter children were filling the swelling ranks of participants and not adults, they are confident participant safety was not compromised.
"There are 6,000 people in the [safety] letter, but they are grown people, and, as we know, the average weight of a child is around half that of an adult," said festival public relations manager Inga Vasiljeva.
Having such large number of singers on stage was common practice, the organizers said, citing previous concerts at the venue. indicates Festival organizers, explaining - as a lot of singers on stage were in the number of pupils in previous holidays.
Also recommended number of participants exceeded the recently occurred in the North and Baltic Song Festival, when the scene was about 8000 singers - adult people.
As children fainted during a final rehearsal for Sunday's closing concert late on Saturday, Education Minister Marite Seile said a planned parade of participants Sunday morning would be cancelled as the cause of the collapses was not known.
She was immediately subjected to heavy criticism via social media with some calling for her resignation - a surprising development as her mistake seemed to have been caution in dealing with a health threat to minors.
After considering resignation, Prime Minister Laimdota Straujuma persuaded her to stay in her job.
The full causes of the incident are under investigation but no official conclusion has been reached.