The Ganges (Ganga) River runs through northern India and is sacred to those who follow Hinduism. More than four hundred million people in India live in the area that feeds the river, known as the Ganges River Basin. A river basin is a region that is drained by a river, such as the Ganges, and any of its tributaries. This means that surface water and rainwater in the basin area flow into the nearby rivers.

The Ganges River originates in the Himalaya Mountains at Gomukh, the terminus of the Gongotri Glacier. When the ice of this glacier melts, it forms the clear waters of the Bhagirathi River. As the Bhagirathi River flows down the Himalayas, it joins the Alaknanda River, officially forming the Ganges River. The Ganges River Basin is sometimes considered part of a larger river basin consisting of the nearby Brahmaputra and Meghna rivers. Known as the Ganges-Brahmaputra-Meghna (GBM) River Basin, it is one of the largest river systems in the world.

The melting water from the Himalayas, as well as water from tributaries and rainfall, all feed the sacred river. The Ganges flows south and east from the Himalayas, forming a canyon as it leaves the mountain. It winds its way through northern India, eventually emptying into the Bay of Bengal. The Ganges’ many tributaries originate from the nearby countries of Nepal, Bangladesh, and China (in an autonomous region called Tibet).

The Ganges River carries nutrient rich sediment as it flows, depositing fertile soil along its shores. This has allowed civilizations to develop and thrive along the waterway for centuries. Today, the river flows through well-populated regions of India, providing fresh water to the millions of people living in these regions. The river is also used for fishing, irrigation, and bathing, and it is worshiped in the Hindu religion as the Mother Ganga. As the river empties into the Bay of Bengal, the mouth forms the Ganges River Delta, the largest river delta in the world.

The Ganges River is a vital resource to Asia, but it faces many threats. Human and industrial pollutants fill the river in some areas, making it unsafe even for swimming. As the population in regions surrounding the river swells, water demands for agriculture increases, straining water levels. Adding further stress to the situation, scientists have concluded that climate change has led to a decrease in glacial ice in the Himalayas, the source of the Ganges, and theorize this will result in further decreased water levels in the river over time.