Explain the key factors that contribute to the uneven distribution of water resources in Karnataka
Answer:-
Karnataka, located in the southern part of India, is endowed with a diverse topography and climate. It has several river basins such as the Krishna, Cauvery, Tungabhadra, and others. Despite having multiple sources of surface and groundwater, the distribution of water resources is highly uneven across the state—both spatially and temporally.
This unevenness is caused by a complex interplay of geographic, climatic, geological, and human-induced factors, leading to water scarcity in some regions while others enjoy relatively abundant resources.
Key Factors Contributing to Uneven Water Distribution:
a) Geographic and Topographic Variations:
- Karnataka can be divided into three major physiographic regions:
- Coastal Karnataka
- Malnad (Western Ghats)
- Bayalu Seeme (plains of the Deccan plateau)
- The Western Ghats receive high rainfall, leading to lush rivers and streams.
- In contrast, North Karnataka, especially the interior districts like Bagalkot, Vijayapura, Raichur, and Koppal, are semi-arid with minimal rainfall and fewer perennial water sources.
b) Uneven Rainfall Distribution:
- Karnataka experiences high rainfall in the western coastal districts (Udupi, Dakshina Kannada) with annual rainfall > 3500 mm.
- However, central and northern districts (like Kalaburagi, Ballari, and Chitradurga) receive less than 700 mm/year.
- This discrepancy results from the rain-shadow effect caused by the Western Ghats, which blocks the southwest monsoon winds from reaching inland areas.
c) River Basin Imbalance:
- Major rivers like the Cauvery, Krishna, and Tungabhadra flow across multiple states.
- Cauvery Basin in the south has better-managed irrigation infrastructure and perennial flows.
- Northern Karnataka, part of the Krishna Basin, receives less share of river water due to inter-state disputes (e.g., with Maharashtra, Telangana).
- Inter-basin transfers are limited, leading to regional water stress.
d) Groundwater Availability and Depletion:
- Groundwater is an essential source in dry regions.
- However, in areas with hard rock geology (Deccan Plateau), aquifers are shallow and poorly recharged.
- Over-extraction of groundwater for irrigation and drinking has led to declining water tables, especially in districts like Tumkur, Kolar, and Chikkaballapur.
e) Agricultural Practices:
- Regions cultivating water-intensive crops (e.g., paddy, sugarcane) consume a large share of water.
- Southern Karnataka (Mandya, Mysuru) uses more water due to canal irrigation from Cauvery.
- In contrast, dryland farming in the north has less water access, and irrigation projects are underdeveloped or inconsistent.
f) Urbanization and Industrial Demand:
- Cities like Bengaluru have growing populations and industries, increasing the urban water demand.
- Water is diverted from rural areas to cities, widening the rural-urban water gap.
- Wastewater pollution from urban areas also degrades downstream water quality, affecting other users.
g) Lack of Integrated Water Management:
- Karnataka lacks a state-wide integrated water resource management (IWRM) strategy.
- Water projects are often developed regionally or politically motivated, not based on scientific need or sustainability.
- Lack of coordination among departments leads to inefficient use and regional imbalance.
h) Climate Change and Monsoon Variability:
- Erratic monsoons and changing rainfall patterns due to climate change make some regions more vulnerable.
- Drought-prone districts experience frequent crop failure, water scarcity, and migration.
Regional Imbalance Snapshot:
| Region | Rainfall (mm/year) | Major Rivers | Water Status |
|---|---|---|---|
| Coastal Karnataka | >3500 | Netravati, Sharavati | Surplus, well-fed |
| Malnad Region | 1500–3000 | Tunga, Bhadra | Moderate–High |
| South Karnataka | 800–1200 | Cauvery | Moderately sufficient |
| North Karnataka | <700 | Krishna, Bhima | Deficient, drought-prone |