The Himalayan rivers of India are perennial.

Answer: Because they get water both from melting snow and glaciers and from monsoon rain.

• Rivers such as the Ganga, Indus and Brahmaputra rise in the snow-covered Himalayas and are fed by glaciers.
• In summer the snow and ice melt and supply water to these rivers; in the rainy season they also receive heavy monsoon rainfall.
• So they have water throughout the year, i.e. they are perennial. In contrast, most peninsular rivers depend only on rainfall and carry little water in summer.