Hallingdal River has a total length of  and a catchment area of . The river falls  in its journey to Krøderen, which is  above sea-level. There are many hydro-electric power stations in the valley with an annual power production of about 4 TWh.
The Hallingdal River has a total length and a drainage area; it descends from its source to Krøderen, which is at a certain elevation above sea level. There are hydroelectric power stations in the valley that generate approximately 4 TWh of energy annually.