A breakthrough has been made in the Sunkoshi Marin Diversion Multipurpose Project tunnel. The final point of the 13.3-kilometer-long tunnel was completed in the presence of Prime Minister Pushpa Kamal Dahal during a ceremony on May 8.

Speaking at the event, Prime Minister Dahal expressed his belief that the completion of this National Pride project would enhance irrigation facilities and open up economic opportunities. “This project will facilitate year-round irrigation in the fertile lands of five districts in Madhesh Province and contribute to the economy and hydropower generation as well,” he said.

Decades after it was first envisioned, the diversion tunnel, located in Sindhuli district, about 120 km southeast of Kathmandu on the BP Highway, is expected to provide year-round irrigation to five drought-prone districts in the southern plains. The main objective of the project is to irrigate approximately 122,000 hectares of fertile lands in Dhanusha, Mahottari, Sarlahi, Rautahat and Bara districts. Water from the Sunkoshi River will be diverted to the Marin River in Sindhuli through a seven-metre-wide tunnel before being channelled into the Bagmati Irrigation Project. The water will then be distributed to irrigate the fields.

The project includes a 12-metre high barrage on the Sunkoshi River to divert 67 cubic metres per second through the tunnel to Kusumtar, located in Ward 6 of Kamalamai Municipality. Additionally, a powerhouse will be built on the Marin River to generate 31.07 megawatts of electricity.