Glaciers in northern Bhutan, which cover about 10 percent of the total surface area, are an important renewable source of water for Bhutan's rivers. Fed by fresh snow each winter and slow melting in the summer, the glaciers bring millions of liters of fresh water to Bhutan and downriver areas each year. Glacial melt added to monsoon-swollen rivers, however, also contributes to flooding and potential disaster.

Data as of September 1991