The middle section of the dam collapsed on 1 December 1923, forty days after the reservoir was filled, causing widespread flooding that killed at least 356 people.

In 1921, because of lack of funding, the project design was changed from a gravity dam to a multiple-arch type.

The failure of the multiple arch dam was attributed to many aspects of its construction, ultimately poor workmanship.

The concrete in the arches was of a poor quality and it was reinforced with anti-grenade scrap netting that had been used during World War I.

[4] A much smaller dam was built spanning the gap left by the collapse, and is still in use today, creating a minor reservoir.