Cauvery Crisis: Karnataka Faces Inflated Water Discharge Requirements to Meet Biligundlu Targets
Hydrological experts warn Karnataka must release up to 7,000 cusecs daily to ensure 3,500 cusecs reach the Tamil Nadu border. Parched riverbeds and significant evaporation losses threaten the state's dwindling reservoir storage.
The Mathematics of Transmission Loss
While the Cauvery Water Regulation Committee (CWRC) has mandated a daily release of 3,500 cusecs to Tamil Nadu over the next 15 days, the physical reality of the riverbed presents a steep challenge for Karnataka. Hydrology experts indicate that to guarantee this volume at the Biligundlu inter-State measuring gauge, the actual outflow from the KRS and Kabini reservoirs may need to reach 6,000 to 7,000 cusecs.
This discrepancy arises from systemic transmission losses. Currently, the riverbed and banks leading to Biligundlu are critically dry. Water released must first saturate the arid banks, replenish groundwater levels, and account for bank storage before the flow can be recorded at the border gauge. Officials estimate that nearly half of the initial discharge could be lost to these natural factors before reaching its destination.
Current Storage and Deficit Data
The latest data from July 28 highlights a precarious situation in Karnataka's Cauvery basin:
- Total Basin Storage: 63.23 tmcft, representing only 55% of the 114.57 tmcft total capacity. This is a sharp decline from the 108.68 tmcft recorded during the same period last year.
- KRS Reservoir Status: Storage has plummeted to just 34% of its capacity. Current operations show an outflow of 1,745 cusecs against an inflow of 2,552 cusecs.
- Kabini Reservoir Status: Outflow is maintained at 300 cusecs despite a higher inflow of 3,594 cusecs.
- Combined Discharge: While 2,045 cusecs are currently being released, this volume is expected to deplete significantly en route to the border.
Environmental and Legal Hurdles
The state's reliance on the southwest monsoon, which typically provides 75% of its annual precipitation, has left it vulnerable during this weak season. Karnataka is grappling with a 35% rainfall deficit, while the primary catchment area in Kodagu reports a 45% shortage. These factors underscore the government's concern regarding drinking water security.
Water Resources Minister K. Ramalinga Reddy indicated the state may challenge the CWRC directive before the Cauvery Water Management Authority. Legal and technical teams are expected to present evidence regarding the unsaturated riverbeds, failing groundwater tables, and the critical need to prioritize human consumption over irrigation during this hydrologically lean period.
Source: The Hindu — News
