Hours before the launch of dam, a portion of the Rs 389-crore dam in Bihar came crumbling down during a trial run on Tuesday and left parts of a town in Bhagalpur flooded, causing huge embarrassment to Bihar government in the state.

Bihar Chief Minister Nitish Kumar was forced to cancel the inauguration on Wednesday. The dam is part of the ambitious Getashwar Panth Canal Project.

According to sources, the wall of the canal collapsed when water from the river Ganga crashed into it after the pump was switched on for a trial and resulted in the inundation of a large part of residential areas and the National Thermal Power Corporation (NTPC) plant in Kahalgao.

The Principal Secretary of the Water Resources department, Arun Kumar Singh, and top Bhagalpur officials are overseeing efforts to drain out water from the submerged areas around 3 km from the canal.

“Sandbags are being placed to check the flow of water,” Mr Singh told media. Experts blame the collapse on the negligence of officials.

The Rs 389.31 crore project has a total irrigation capacity of 27,603 hectares out of which 22,816 is in Bihar and 4,887 hectares in Jharkhand.

The Planning Commission had originally approved the project in 1977 at an estimated cost of Rs 13.88 crore. The first administrative approval to the project was provided in 2008 involving a cost of Rs 389.31 crore, the brochure said.

According to media reports, former Bihar deputy Chief Minister Tejashwi Yadav blamed rampant corruption under Nitish Kumar government for the accident.