The Tama Koshi River (grade 4 to 6) starts from the Tserolpa Lake and Gaurishanker Glacier, Rafting/Kayaking starts from Busti (a bridge on the way to Jiri) There are some copper mines around this river (Tama = copper and Koshi = river, hence the name). Actually this river is too wild for commercial run because it has 4 to 6 grade rapids and some of the rapids are unrunable but for the Kayakers this river is excellent.
Recently a hydroelectricity power plant (The Khimti Project) has been constructed in the Khimti area alongside the river. After three days of Kayaking on this river, one would come to the Sunkoshi River just above Khurkot then another 4 days paddling down arriving at Chatara at the banks of Saptakoshi River which is also called Baraha Chhetra, the famous Hindu pilgrimage. This trip is considered as the most adventurous and dangerous river trip.