Uhl river originates from the Thamsar glacier which is situated in the Dhauladhar ranges of the Himalayas and flows through the Uhl valley passing Bada Gran and Barot village. Uhl river is the water basin of the Beas river. Uhl river is also known as Tiun Nala and the Uhl valley is also famous as Chohar valley. After crossing the Chohar valley, Uhl river meets the Beas river 5 km downstream from Pandoh.
The hydroelectric projects oh Uhl river have been divided in three stages.
Uhl originates from the Thamsar Glacier in higher Dhauladhar range. Uhl reaches Palachak, where a tributary joins it from the right bank. 18 km downstream at Barot, Uhl is joined by Lumba Dugh from the left bank. Lumba Dugh also flows along the Luhrdi before merging Uhl.