Introduction
India's drainage systems are vital natural assets supporting approximately 18% of the global human population with only 4% of the world's freshwater resources. However, highly skewed monsoonal hydrographs and anthropogenic stresses transform these resource arteries into sources of acute regional vulnerability, manifesting as devastating floods, siltation, and interstate conflicts.
Geomorphic, Environmental, and Institutional Challenges
Drainage basin management in India is impeded by an interplay of geomorphic dynamics, regulatory shortcomings, and ecological disruptions across catchments:
- Hydro-Geomorphological Stress: Widespread deforestation in upper catchments accelerates topsoil erosion, driving severe reservoir siltation. Channel siltation reduces river carrying capacity and triggers dramatic channel avulsions, as observed historically in the Kosi basin.
- Institutional and Legislative Fragmentation: Water governance suffers from an institutional hydro-geological disconnect, where surface water managed by the Central Water Commission (CWC) and groundwater managed by the Central Ground Water Board (CGWB) are administered in administrative silos.
- Dormant Legislative Mechanisms: The River Boards Act, 1956 has largely remained unutilised, undermining inter-state basin-level coordination and exacerbating protracted riparian disputes across basins such as the Cauvery and Krishna.
- Floodplain Encroachment and Urban Squeeze: Rapid urbanisation over natural wetland buffers alters local drainage hydrographs, converting moderate precipitation events into catastrophic urban deluges, as seen in Chennai and Bengaluru.
Measures for Sustainable Integrated River-Basin Management (IRBM)
Achieving sustainable management requires transitioning from sectoral engineering projects to comprehensive, basin-scale eco-hydrological frameworks:
- Institutional Unification: Implement the recommendations of the Mihir Shah Committee (2016) by merging the Central Water Commission and the Central Ground Water Board into an apex National Water Commission (NWC) to integrate surface and subsurface hydrology.
- Statutory Restructuring: Enact modern basin-level legislation, such as the Draft River Basin Management Bill (2018), to replace the outdated 1956 framework with autonomous River Basin Authorities for transboundary basin planning.
- Eco-Hydrological Rejuvenation: Mandate and monitor dynamic Environmental Flows (E-flows) across dammed rivers to maintain downstream ecological viability and flushing capacities.
- Integrated Catchment and Floodplain Protection: Execute catchment afforestation to arrest silt yield, delineate active floodplains as inviolable zones, and promote conjunctive water-use policies aligned with Sustainable Development Goal 6.
Conclusion
Transitioning from fragmented water exploitation to Integrated River Basin Management is imperative for building regional climate resilience. Institutional unification coupled with eco-hydrological restoration will reconcile the dual imperative of harnessing river resources while mitigating hydro-meteorological vulnerabilities.