Drainage

• Introduction to Drainage
  • Drainage: River system of an area
  • Drainage Basin: Area drained by a single river system
  • Water Divide: Elevated area separating two drainage basins (e.g., Ambala)
  • River Regimes: Himalayan (Perennial) vs. Peninsular (Seasonal)
• Drainage Systems in India
  • Classification
    • Himalayan Rivers
    • Peninsular Rivers
  • Himalayan Rivers
    • Characteristics: Perennial, high erosion, long courses
    • Indus River System
      • Origin: Tibet (Mansarovar Lake)
      • Major Tributaries: Jhelum, Chenab, Ravi, Beas, Satluj
      • Indus Water Treaty (1960)
    • Ganga River System
      • Origin: Gangotri Glacier (as Bhagirathi)
      • Junction with Alaknanda at Devprayag
      • Major Tributaries: Yamuna, Ghaghara, Gandak, Kosi
      • Sundarbans Delta: World's largest and fastest-growing delta (formed with Brahmaputra)
    • Brahmaputra River System
      • Origin: Tibet (East of Mansarovar, known as Tsangpo)
      • Enters India in Arunachal Pradesh (Dihang)
      • High silt deposition, braiding, and floods (Assam)
  • Peninsular Rivers
    • Characteristics: Seasonal, shorter/shallower courses, broad valleys
    • Mahanadi River
      • Origin: Highlands of Chhattisgarh
      • Drains into: Bay of Bengal
    • Godavari River
      • Largest Peninsular river (Dakshin Ganga)
      • Origin: Nasik district (Maharashtra)
      • Drains into: Bay of Bengal
    • Krishna River
      • Origin: Spring near Mahabaleshwar
      • Major Tributary: Tungabhadra, Bhima
    • Kaveri River
      • Origin: Brahmagiri range (Western Ghats)
      • Drains into: Cuddalore (Tamil Nadu)
    • Narmada Basin
      • Origin: Amarkantak hills
      • Flows through a Rift Valley due to faulting
      • Dhrandhar Falls near Jabalpur
    • Tapi Basin
      • Origin: Satpura ranges (Betul, MP)
      • Parallel to Narmada, shorter length
• Lakes
  • Definition: Large water bodies enclosed by land
  • Types of Lakes
    • Freshwater Lakes (e.g., Wular Lake - tectonic origin, Dal Lake)
    • Saltwater / Saline Lakes (e.g., Sambhar Lake - salt production)
    • Artificial Lakes (e.g., Guru Govind Sagar - Bhakra Nangal Project)
  • Importance: Regulate river flow, tourist attraction, hydropower generation, aquatic ecosystem
• Role of Rivers in the Economy
  • Source of fresh water for agriculture (irrigation)
  • Navigation and transport
  • Hydropower generation
  • Development of civilizations along river banks
• River Pollution
  • Causes
    • Domestic sewage and industrial effluents discharge
    • Untreated waste dumping
    • Religious and cultural practices
  • Government Initiatives
    • National River Conservation Plan (NRCP)
    • Namami Gange Programme (Integrated Ganga Conservation Mission)