Biodiversity of Bihar

Mapping Bihar's river systems and wetlands — from the Ganga and its tributaries to natural and constructed water bodies. Content and images coming soon.

Ganga

Ganga

The Ganga enters Bihar near Chausa in Buxar district and flows roughly 445 km eastward through Patna, Bhagalpur and beyond before exiting into West Bengal. It is Bihar's principal river system, sustaining agriculture, fisheries and the endangered Gangetic dolphin along its course.

Buxar to Bhagalpur and beyond, west-east across northern Bihar

Himalayan Tributaries of Ganga

Himalayan Tributaries of Ganga

Rivers such as the Gandak, Kosi, Bagmati and Kamla Balan originate in the Nepal Himalayas and enter Bihar from the north. Carrying heavy silt and monsoon flow, they shape North Bihar's fertile but flood-prone alluvial plains and are central to the state's flood-management concerns.

North Bihar, flowing south from the Nepal Himalayas

Plateau Tributaries of Ganga

Plateau Tributaries of Ganga

Rivers including the Sone, Punpun and Falgu rise in the Chotanagpur plateau to Bihar's south and join the Ganga from the right bank. More rain-fed and seasonal than the Himalayan rivers, they are vital for irrigation across South Bihar's drier districts.

South Bihar, rising in the Chotanagpur plateau

Minor Tributaries and Streams

Minor Tributaries and Streams

Numerous smaller rivers and seasonal streams — including the Chandan, Badua and Ghaghra — feed into Bihar's major river systems. Though modest in size, they support local irrigation, groundwater recharge and village-level fisheries across both North and South Bihar.

Distributed across North and South Bihar

Sub-Basins

Sub-Basins

Bihar's river network is organised into major sub-basins — Gandak, Kosi, Sone and Bagmati among them — each draining a distinct part of the state. This sub-basin structure underlies water-resource planning, flood forecasting and irrigation management across Bihar.

State-wide — organised by major river drainage areas

Wetlands (1. Natural, 2. Dams & Reservoirs)

Wetlands (1. Natural, 2. Dams & Reservoirs)

Bihar's wetlands include natural oxbow lakes and chaurs such as Kanwar Jheel in Begusarai and Gogabil in Katihar, alongside constructed reservoirs like the Nagi and Nakti dams in Jamui. Together they are critical habitat for migratory waterfowl and freshwater fish.

Statewide — e.g. Kanwar Jheel (Begusarai), Gogabil (Katihar), Nagi-Nakti dams (Jamui)