The Kankai Irrigation System (KIS) has an office in Gainde, Jhapa district, Nepal's Province No. 1. The KIS weir type headworks is located in Domukha, Jhapa district, about 3 km north of the E-W highway Kankai Bridge at Gainde. The debouching point of the Kankai River from the slope to the terai plain was chosen as the diversion weir site. The headwork is located at latitudes 26041'6"N and 87025'44"E. The Kankai River, a tributary of the Ganges River, is the KIS's source river. The Kankai River, which originates in Nepal's Mahabhrat Range, is classed as a second-class river. It meets the Mahananda in the Kishanganj district of Bihar, India, during its flow.

The Kankai Irrigation Project (KIP) was originally developed as an initial stage of agricultural development in the Kankai River Basin to irrigate about 5000 ha of existing farm land, leaving a potential of total 10000 ha of paddy land to develop in the near future using year-round irrigation facility.