A breakthrough has been made in the Sunkoshi Marin Diversion Multipurpose Project tunnel.

The final point of the 13.3-kilometre-long tunnel was completed in the presence of Prime Minister Pushpa Kamal Dahal amid a function on Wednesday.

Speaking at the event, Dahal expressed his belief that the completion of the National Pride project would provide better irrigation facilities and would also open economic opportunities once brought into operation.

“This project will facilitate year-round irrigation in fertile lands of five districts of the Madhesh Province, and will contribute to the economy and hydropower generation as well,” the prime minister said.

Highlighting that the agricultural sector was the backbone of the Nepali economy and development, contributing to about a third of the total GDP, Prime Minister Dahal added that the increase in agricultural production would help the country become self-sufficient in food supply, and ensure food security.

Increased agricultural productivity will also help decrease the yawning trade deficit, he further added.

Decades after it was envisioned, the diversion tunnel, located in Sindhuli district, about 120 km southeast of Kathmandu, on BP Highway, is expected to provide a round-the-year irrigation facility to five drought-prone districts in the southern plains.

The main objective of the project is to provide irrigation facilities in around 122,000 hectares of fertile lands in Dhanusha, Mahottari, Sarlahi, Rautahat and Bara districts.

Water from the Sunkoshi will first 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 also features a 12-metre high barrage across the Sunkoshi River to divert a discharge of 67 cubic metres per second through the tunnel to Kusumtar located in Ward 6 of Kamalamai Municipality. A powerhouse will be built on the Marin River to generate 31.07 megawatts of electricity.