Drainage System:
- Network of primary and secondary rivers channeling surface water into seas, lakes, or water bodies.
Drainage Basin: Area drained by these rivers.
Importance: Provides water, transportation, electricity, and livelihood.
Categories Based on Location:
- Himalayan Rivers - Perennial rivers originating from the Himalayas, mainly flowing through North India.
Peninsular Indian Rivers
Himalayan Rivers:
Indus River Basin:
Length: 2,850 km (709 km in India).
Origin: Near Lake Mansarovar, Tibet, at 5,150 meters.
Drainage Area: 1,165,500 sq. km (321,289 sq. km in India).
Flow Path: Through Ladakh, Jammu & Kashmir, enters Pakistan, empties into the Arabian Sea.
Major Tributaries: Jhelum, Chenab, Ravi, Beas, Sutlej.
Largest Tributary: Chenab.
Ganges River Basin:
Area: 861,404 sq. km (Largest in India).
Population: Densely populated along banks.
Origin: Bhagirathi from Gangotri Glacier, Uttarakhand, at 7,010 meters.
Length: 2,525 km.
Northern Tributaries: Gomti, Ghaghara, Gandak, Kosi.
Southern Tributaries: Yamuna, Son, Chambal.
Bangladesh: Called Padma River.
Delta: Ganges and Brahmaputra form the world’s largest delta, empties into the Bay of Bengal.
Brahmaputra River Basin
Origin: Near Lake Mansarovar in Tibet, from the Chemayungdung Glacier at an altitude of 5,150 meters.
Total Drainage Area: 580,000 sq. km (194,413 sq. km in India).
Length: 2,900 km (900 km in India).
Tibet: Known as Tsangpo (Purity).
Entry into India: Through the Dihang Gorge in Arunachal Pradesh.
Major Tributaries: Teesta, Manas, Barak, Subansiri.
Bangladesh: Known as Jamuna; merges with the Ganges and called Meghna.
Characteristics of Himalayan Rivers:
Origin: From the Himalayas.
Length & Breadth: Long and wide.
Type: Perennial rivers (flow year-round).
Challenges: Not suitable for hydropower generation.-
Transport: Ideal for navigation in middle and lower course.
Peninsular Indian Rivers:
Location: Flow through Southern India.
Origin: Mostly from the Western Ghats.
Type: Seasonal or non-perennial rivers; water levels vary with rainfall.
Flow Path: Pass through steep valleys.
Division Based on Direction:
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East-flowing rivers.
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West-flowing rivers.
East-Flowing Rivers:
Mahanadi:
Origin: Near Sihawa in Raipur district, Chhattisgarh.
Length: 851 km, flows through Odisha.
Major Tributaries: Seonath, Tel, Sandur, Chitrotpala, Kenguti, Nand.
Delta: Forms one of India’s largest deltas before merging into the Bay of Bengal.
Godavari:
Length: 1,465 km (Longest river in Peninsular India).
Origin: Western Ghats, Nashik district, Maharashtra.
Drainage Area: 313,000 sq. km.
Tributaries: Purna, Penganga, Pranhita, Indravati, Tal, Salami.
Delta: Splits into two branches (Gautami and Vashishta) near Rajahmundry, creating a large delta.
Kolleru Lake: A freshwater lake located in the Godavari delta region.
Krishna:
Origin: Mahabaleshwar, Western Ghats, Maharashtra.
Length: 1,400 km (Second-largest in Peninsular India).
Drainage Area: 258,000 sq. km.Tributaries: Koyna, Bhima, Musi, Tungabhadra, Pedavagu.
Mouth: Enters the Bay of Bengal near Hamsaladeevi in Andhra Pradesh.
Cauvery:
Origin: Talakaveri in Kodagu, Karnataka.
Length: 800 km.
Tributaries: Harangi, Hemavati, Kabini, Bhavani, Arkavati, Noyyal, Amaravati.
Special Features: Known as the “Ganga of the South.”
Flow: Forms sacred islands like Srirangapatna and Shivanasamudra in Karnataka, passes through the Okenakkal Falls in Tamil Nadu, and finally splits into Kollidam and Cauvery near Srirangam, emptying into the Bay of Bengal near Poompuhar.