A committee formed to investigate Melamchi tunnel incident has concluded that one of the sluice gates on the tunnel of the Melamchi Water Supply Project had broken due to a technical error.

A project’s engineer and driver died due to the flood resulting from the breakage of the sluice gate while carrying out trial by releasing water in the tunnel two weeks ago.

The Ministry of Water Supply and Sanitation had constituted an investigation committee under the convenorship of Joint Secretary Ramakanta Dawadi to look into the causes of the incident and submit a report.

The investigation committee has concluded that the mishap took place as the gate had been fixed from outside instead of inside of the tunnel. It also stated that the technical design review had not been carried out lately.

The committee has suggested carrying out a review of all the four sluice gates in the tunnel. It said it found the nuts and bolts in the gates have not been tightened properly.

Water that had accumulated for up to one week had gushed out of the tunnel when the sluice gate opened at the project construction site at Helambu rural municipality-1 in Sindhupalchowk district while carrying out the test to assess the tunnel’s function, leading to flood.

Project consultant Dorje Pemba and engineer Shekhar Khanal had been injured in the incident. Engineer Satish Gohit and driver Radha Krishna Thapa Magar had gone missing after being swept away by the flood. The body of engineer Gohit was found the next day of the accident took place while Thapa Magar is still missing.

It is said it takes around 15 days to fill water for carrying out the test of the tunnel. But the water had found its way out only within a week’s time, breaking the sluice gate. The accident took place on July 14. The water had been diverted to the tunnel from the Melamchi river for carrying out the trial on July 5.

Ministry’s spokesman Ritesh Kumar Shakya said the consulting company and the company that constructed the sluice gates should own up to the accident. According to him, Itas Company is the consultant company while the Indian company, PIL, had constructed the gate. The Italian company, CMC, which carried out works of the Project before had hired PIL company for the construction of the sluice gates of the tunnel.