3.2.8. The Ganga Plains

The Ganga plains lie between the Yamuna catchment in the west to the Bangladesh border in the east. It is about 1400km in length and has an average width of 300km. the general gradient of the plain is about 15cm per km. The ganga plains can be subdivided into the following sub- regions

♤ The upper Ganga plain – includes the Ganga-Yamuna Doab, Rohilakhand division and parts of the Agra division. The catchment area of the Yamuna river makes its western boundary, Shiwalik in the north. Its height varies from 100m to 300m. Kali, Sharda are other rivers feeding these plains. It is one of the most productive plains of India in which the Green revolution is a big success. Main crops grown here are sugarcane, wheat, rice, maize, mustard, vegetables etc.

♤ The middle Ganga plain – sprawling over an area of 150, 000 sqkm, it includes central and eastern Uttar Pradesh, Bihar up to Muzaffarpur and patna. It has thick alluvial deposits with

less kankar. Being a low gradient plain, the rivers often change their courses in this region as described above about Kosi river. Son, Gandak are major tributaries of Ganga.

♤ The lower ganga plain – extends from Patna to the Bay of Bengal. It is bordered by Assam, Bangladesh in the east and Chotanagpur plateau in the west and Sundarban delta in the south. It is drained also by Tista, Sankosh, Mahananda, Damodar, Subarnarekha rivers. These plains have filled faults with sediment created during movement of Indian plate. Ganga is divided into several distributaries in the delta region. Hooghly is the best example of a distributary of Ganga.