Koshi Barrage

The Koshi Barrage is a sluice across the Koshi river that carries vehicular, bicycle, and pedestrian traffic between Saptari district and Sunsari district of Nepal. It is near the International border with India. It was built between 1958 and 1962 and has 56 gates. It was constructed after the Koshi Agreement was signed between the Government of Nepal and India on April 25, 1954. The barrage was designed and built by Joseph and Company Limited, India. The Koshi Tappu Wildlife Reserve is roughly 3–4 miles north of the barrage.

2017 flood
Every year several areas of Terai are affected due to the flood and blockage of this barrage. This affects mostly the Koshi region of Bihar (Supaul, Saharsa, Madhepura and Purnia). The Kosi River is known as the "Sorrow of Bihar" as the annual floods affect about 21000 km2 of fertile agricultural lands thereby disturbing the rural economy. The Koshi has an average water flow (discharge) of 2166 m3/s.

2008 flood
In August 2008, the eastern embankments of the Koshi Barrage collapsed, several miles north of the Nepal-India border. The resulting flood wiped out miles of fertile farmland in Nepal, covering it with a thick layer of river sand, and affected 53,800 Nepalese. It left 3 million people homeless in Bihar, India.

Tourism
This river is home to the Gangetic Dolphin and other different species of fresh water fish. Siberian birds can be seen there easily during the month of August–October. People usually visit there to have the varieties of fish dishes in the nearby riverside restaurants and see the scenic view from the barrage.

Air transport
Rajbiraj Airport is the nearest airport roughly 26 km away is located in district headquarter and nearest city Rajbiraj. Shree Airlines and Buddha Air operates daily flights between Rajbiraj and Kathmandu