Prelims – Current events of national and international importance| Geography
Why in News?
Uttar Pradesh informed the National Green Tribunal (NGT) that physical demarcation of the Ganga floodplain zone has been completed along nearly 700 km in the State.
- Stretch covered – Unnao to Ballia covering 13 districts.
- Length – Approximately 700 km with installed 7,350 pillars.
- Purpose – To identify and physically mark the floodplain to prevent encroachment, unauthorised construction and other activities.
- The work supports the objectives of the River Ganga Authorities Order, 2016 and earlier NGT directions.
Ganga floodplain
- It is the low-lying land flanking the Ganga river that naturally absorbs excess water during high-flow periods.
- It performs important ecological functions such as –
- Floodwater storage
- Groundwater recharge
- Sediment deposition
- Aquatic and terrestrial habitat
- Maintaining the river’s natural flow dynamics.
- Tributary Status in Uttar Pradesh
- Demarcation is the physical and legal process of mapping, marking, and dividing the low-winning land next to the Ganga River that collects overflow during high water.
- Under the National Mission for Clean Ganga via the August 2026 amendment, the government redefined it into three distinct zones based on flood frequency.
- Active Flood Plain – Submerged at least once every 5 years; strictly protected.
- Regulatory Zone – Flooded once every 5 to 25 years; construction allowed with specific approvals.
- Warning Zone – Flooded once every 25 to 100 years; development permitted with official clearances.
Ganga River System
- It is the largest drainage network in India, spanning 2,525 km from the Himalayas to the Bay of Bengal.
- Source – Ganga river starts as the Bhagirathi from the Gangotri Glacier at Gaumukh in Uttarakhand.
- Formation – It becomes the Ganga at Devprayag after joining the Alaknanda river.
- It leaves the mountains and enters the plains at Haridwar.
- Flows through – Uttarakhand, Uttar Pradesh, Bihar, Jharkhand, and West Bengal.
- Termination – It empties into the Bay of Bengal after forming the world's largest delta (the Sundarbans) with the Brahmaputra river
Reference
Hindustan Times| Demarcation of Ganga Flood Plain
