Four engineers have been suspended for the breach in the embankment of the Konar Irrigation Project in Jharkhand, which collapsed within 24 hours of its inauguration, a report said on Sunday.
The Water Resources department had formed a three-member committee to probe the cause of the damage.
The report submitted to the department said "the incident was caused due to closure of escape regulator due to which the pressure of water increased and the weaker part of the canal washed away".
It took 42 years to build the Konar irrigation project, while it collapsed within 24 hours of its inauguration. It was meant to provide water to 85 villages across Giridih, Hazaribagh and Bokaro districts of Jharkhand.
The state administration, in its initial probe report, had blamed rodents for the breach.
The irrigation project in Giridih district was dedicated to the people by Chief Minister Raghubar Das on August 28.
Within 24 hours of its inauguration, a major breach developed in the canal, causing extensive flooding in several villages.
"The initial probe suspected 'rat holes' causing damage to the canal," said the government statement released on August 30.
A three-member probe committee headed by Chief Engineer Sanaullah visited the spot, inquired into the incident and submitted its report.
The committee found that 600 meters below the damaged site, there was an escape channel which was kept open to ensure normal flow of water, but it was closed perhaps through some mischief or some other unknown reason.
According to the report, a 28-30 meter area of the canal was damaged and crops spread over 10-15 acres of land got submerged.
In 1978, the then Governor of undivided Bihar, Jaggananth Kaushal, had laid the foundation stone of the project, but due to several reasons, including the indifference of successive governments, the project got delayed. The cost of the project also escalated from Rs 12 crore in 1978 to Rs 2,500 crore.
In 2003, the then Jharkhand Chief Minister Arjun Munda once again laid the foundation for the canal, but work moved at snail's pace.
In 2012, a tender was again floated for the project, which was bagged by a Mumbai-based company.