Overview

The Western Ghats (Sahyadri) and Eastern Ghats are two parallel hill ranges flanking the Deccan Plateau — the Western Ghats running along the Arabian Sea coast, the Eastern Ghats along the Bay of Bengal coast. Together they form the backbone of peninsular India's river systems, biodiversity, and climate. The Western Ghats is one of the world's eight biodiversity "hottest hotspots" and a UNESCO World Heritage Site (2012). For UPSC, these ranges are tested across Prelims (geography facts) and Mains (GS1 — biodiversity, environment policy).


Western Ghats — Key Facts

FeatureDetails
Other nameSahyadri Mountains
Length~1,600 km — from the Tapti River (Gujarat-Maharashtra border) to Kanyakumari (Tamil Nadu)
Width50–80 km (average)
Highest peakAnamudi (2,695 m) — Kerala; highest peak in India south of the Himalayas
States coveredGujarat, Maharashtra, Goa, Karnataka, Kerala, Tamil Nadu
Average elevation1,200 m (general crest), rising to 2,695 m at Anamudi
UNESCO statusWorld Heritage Site inscribed in 2012 — 39 component sites across 7 sub-clusters

UNESCO World Heritage — 39 Component Sites

The Western Ghats serial nomination (2012) comprises 39 component sites distributed across four states — 20 in Kerala, 10 in Karnataka, 6 in Tamil Nadu, and 3 in Maharashtra — grouped into 7 sub-clusters. The serial nomination was used because no single contiguous site could capture the full range of biodiversity across this 1,600 km range.

Key protected areas within the UNESCO nomination include Nilgiri Biosphere Reserve, Silent Valley National Park, Kudremukh National Park, Periyar Tiger Reserve, and Agasthyamalai Biosphere Reserve.


Rivers Originating in the Western Ghats

The Western Ghats form one of India's principal watersheds, feeding rivers that drain nearly 40% of the country's land area:

RiverStates DrainedKey Feature
GodavariMaharashtra, Telangana, Andhra PradeshOriginates near Trimbakeshwar (Nashik); India's longest peninsular river (1,465 km)
KrishnaMaharashtra, Karnataka, Andhra PradeshOriginates at Mahabaleshwar (1,336 m altitude); 1,400 km long
Cauvery (Kaveri)Karnataka, Tamil NaduOriginates at Talakaveri, Brahmagiri Hills, Coorg; the "Ganga of the South"
TungabhadraKarnatakaMajor Krishna tributary; flows eastward; Hampi on its banks
PeriyarKeralaFlows westward into the Arabian Sea; Periyar Tiger Reserve
SharavathiKarnatakaJog Falls (253 m drop, four cascades — Raja, Rani, Roarer, Rocket) — segmented waterfall that becomes plunge in monsoon; India's tallest plunge waterfall is Nohkalikai, Meghalaya (340 m)

A key feature is the Western and Eastern watershed divide: rivers originating on the western slope of the Ghats (e.g., Periyar, Netravati) are short, fast, and drain westward into the Arabian Sea, while rivers originating on the eastern slope (Godavari, Krishna, Cauvery) are long, slow-moving, and drain eastward into the Bay of Bengal.


Western Ghats as a Biodiversity Hotspot

The Western Ghats is recognised as one of the world's 36 biodiversity hotspots (Conservation International classification). It supports extraordinary species diversity, most of it endemic:

CategoryNumber of SpeciesEndemism (approx.)
Flowering plants~5,000~1,700 endemic
Amphibians~179~87% endemic
Reptiles~157~62% endemic
Birds~508~16% endemic
Mammals~139~12% endemic

Notable endemic species include the Lion-tailed Macaque, Nilgiri Tahr (State animal of Tamil Nadu), Malabar Giant Squirrel, Nilgiri Langur, Malabar civet, and numerous endemic frogs and fish of the Western Ghats.


Hill Stations

Hill StationStateElevationNotable Feature
Ooty (Udhagamandalam)Tamil Nadu2,240 mNilgiri Mountain Railway (UNESCO Heritage); former Madras summer capital
MunnarKerala~1,600 mTea plantations; Eravikulam NP (Nilgiri Tahr)
KodaikanalTamil Nadu2,100 mStar-shaped lake; shola forests; Kurinji flower (blooms every 12 years)
Coorg (Kodagu)Karnataka~1,200 mCoffee and spice estates; Kodava culture
MahabaleshwarMaharashtra1,353 mOrigin of Krishna River; strawberry cultivation
LonavalaMaharashtra~624 mGateway to Sahyadri for Mumbai-Pune corridor

Eastern Ghats — Key Facts

FeatureDetails
NatureDiscontinuous — broken by river valleys; not a continuous range like Western Ghats
Length~1,750 km — from Odisha to Tamil Nadu (some estimates include Gujarat segment)
Average elevation~600 m (significantly lower than Western Ghats)
Highest peakJindhagada Peak (1,690 m), Andhra Pradesh — confirmed highest in 2011; also known as Arma Konda/Sitamma Konda area
Other significant peaksMahendragiri (1,501 m, Odisha-Andhra border)
States coveredOdisha, Andhra Pradesh, Tamil Nadu

The Eastern Ghats are separated by the Mahanadi, Godavari, Krishna, and Cauvery river valleys as they flow east, giving the range its characteristic discontinuous appearance. The terrain is lower, drier, and ecologically distinct from the wet, continuous Western Ghats.


Western Ghats vs Eastern Ghats — Comparison

FeatureWestern GhatsEastern Ghats
ContinuityContinuous rangeDiscontinuous, broken by rivers
Length~1,600 km~1,750 km (discontinuous)
Average elevation~1,200 m~600 m
Highest peakAnamudi, 2,695 m (Kerala)Jindhagada Peak, 1,690 m (Andhra Pradesh)
RainfallVery heavy (windward side gets 2,500–5,000 mm); rain shadow on leeward sideModerate (600–1,000 mm); receives NE monsoon
ForestsTropical wet evergreen and semi-evergreenTropical dry deciduous
RiversSource of Godavari, Krishna, Cauvery, PeriyarCut through by major rivers
UNESCO statusWorld Heritage Site (2012)Not designated
BiodiversityHotspot (globally recognized)Significant but less endemic

Threats to Western Ghats

The Western Ghats faces multiple anthropogenic threats:

  • Deforestation and habitat fragmentation: Expansion of tea, coffee, cardamom, and eucalyptus plantations; road widening projects (NH 66, NH 544)
  • Mining: Iron ore and bauxite mining in Goa and Karnataka (Kudremukh controversy)
  • Hydropower projects: Large dams (Silent Valley, Athirappilly) threatening river ecosystems and forest integrity
  • Invasive species: Lantana camara and Eupatorium have colonised degraded forest edges
  • Western Ghats Ecology Expert Panel (WGEEP/Gadgil Committee, 2011): Recommended declaring 64% of Western Ghats as Ecologically Sensitive Area (ESA); modified by Kasturirangan Committee (2013), which recommended ESA status for 37% (~60,000 km²)

The Kasturirangan report (2013) recommendations remain partially implemented — a long-running controversy over balancing conservation with local livelihoods in six states.


Exam Strategy

Prelims Focus:

  • Anamudi (2,695 m) — highest peak south of Himalayas (Western Ghats, Kerala)
  • UNESCO inscribed in 2012 — 39 component sites
  • Western Ghats = continuous; Eastern Ghats = discontinuous
  • Jindhagada Peak (1,690 m) — highest peak of Eastern Ghats (Andhra Pradesh; confirmed 2011)
  • Rivers: Godavari, Krishna, Cauvery originate in Western Ghats
  • Jog Falls = on the Sharavathi River

Mains Focus:

  • Western Ghats as a biodiversity hotspot: endemism, fragility, WGEEP vs Kasturirangan recommendations
  • Comparison of Western and Eastern Ghats: structure, ecology, rivers
  • Environmental threats and the ESA debate — balancing conservation with development
  • Importance of Western Ghats for India's water security (feeds rivers draining 40% of land area)


Recent Developments (2024–2026)

Wayanad Landslide 2024 — ESA Debate Intensifies

The catastrophic Wayanad landslides of July 30, 2024 (254 confirmed deaths + 118 missing/presumed dead, ~372 total casualties — Kerala's deadliest landslide event) occurred in an area that the Gadgil Committee (2011) had recommended for Ecologically Sensitive Area (ESA) status — protection that would have restricted large-scale agricultural and construction activities. The High-Level Working Group (Kasturirangan Committee, 2013) recommended a less stringent ESA boundary. The 2024 disaster renewed calls to implement the Kasturirangan ESA boundary covering 37% of the Western Ghats as a minimum, and some experts called for a full review using updated satellite mapping and LiDAR data. The Kerala High Court took suo motu cognizance of the disaster and the delayed implementation of ESA notifications.

UPSC angle: Western Ghats ESA, Gadgil vs Kasturirangan panel recommendations, biodiversity conservation vs livelihood rights, and environmental governance are consistently high-priority Mains GS3 and Essay topics.

Green India Mission — Forest Cover Update 2024

The India State of Forest Report 2023 (released by the Forest Survey of India) recorded India's total forest and tree cover at 8,27,357 sq km — 25.17% of India's geographic area. The Western Ghats states (Kerala, Karnataka, Tamil Nadu, Goa, Maharashtra) hold a significant share of India's dense forest cover. However, the report also noted degradation in the Eastern Ghats due to mining, particularly in Odisha and Andhra Pradesh, and expansion of open forests in previously dense forest zones. The Green India Mission (GIM) targets increasing forest/tree cover by 5 million hectares and improving quality on another 5 million hectares by 2030.

UPSC angle: Forest cover data, Green India Mission, Western and Eastern Ghats biodiversity, and forest governance are important for GS3 environment questions.


Sources: UNESCO World Heritage Centre (whc.unesco.org — Western Ghats, list 1342); IUCN World Heritage Outlook; WWF India (wwfindia.org); MoEFCC — Western Ghats Ecology Expert Panel Report (Gadgil, 2011); Kasturirangan Committee Report (2013); Wikipedia (Western Ghats, Eastern Ghats, Arma Konda)