Reservoirs – Cauvery Water Concerns Rise Ahead of Weak Monsoon Season
Reservoirs – Tamil Nadu and Karnataka are preparing for a renewed dispute over Cauvery river water distribution as both states enter the new water year with significantly lower reservoir storage and an uncertain monsoon forecast.
Officials from the Cauvery Water Regulatory Committee and the Cauvery Water Management Authority urged both governments on Tuesday to carefully monitor the extent of paddy cultivation during the coming months. Authorities warned that rainfall shortages during the latter half of the southwest monsoon season, particularly in August and September, could place additional pressure on already strained water resources.
The Cauvery river, which begins in the Western Ghats of Karnataka before flowing into Tamil Nadu, remains a critical source of irrigation for farmers in both states. Paddy cultivation in the Cauvery basin depends heavily on regular monsoon rainfall and sufficient storage in major reservoirs.
Authorities Warn Against Excessive Paddy Cultivation
Representatives attending the CWRC and CWMA meetings stressed the importance of caution while planning paddy acreage this season. Since paddy is one of the most water-dependent crops grown across the Cauvery delta region, any shortage in rainfall could directly affect irrigation availability later in the year.
Vineet Gupta, Chairman of the CWRC, stated after the meetings that the previous water year had remained relatively stable because of abundant rainfall and healthy reservoir levels. However, he noted that the upcoming season may prove more difficult due to forecasts of weaker monsoon activity across the region.
Officials indicated that water management decisions taken in the next few weeks would play an important role in avoiding stress during the peak cultivation months.
Reservoir Levels Show Sharp Decline
Water storage in both Karnataka and Tamil Nadu has dropped considerably compared to the same period last year. Data discussed during the meetings revealed that Tamil Nadu’s Mettur Dam currently holds around 40 TMC of water, nearly half the storage recorded at the end of May 2025.
Last year’s situation was notably different, as excess rainfall during May helped maintain strong storage levels and supported agricultural expansion across delta districts.
In Karnataka, the Krishna Raja Sagara (KRS) reservoir is also witnessing a major decline. The dam currently contains around 8 TMC of water, compared to nearly 21 TMC during the beginning of the previous water year.
Officials fear that if rainfall remains below expectations during June and July, reservoir levels may fall further before the end of the monsoon season.
IMD Forecast Raises Concerns
The Indian Meteorological Department has projected below-normal rainfall for the 2026 southwest monsoon season, which runs from June through September. According to the forecast, rainfall could remain at around 92 percent of the long-period average, with a margin of variation of five percent.
Meteorologists have described the prediction as one of the weaker monsoon outlooks issued in recent years. This has increased concerns among irrigation planners and agricultural authorities in both states.
The contrast with last year remains significant. India recorded above-normal monsoon rainfall in 2025, with seasonal precipitation reaching nearly 108 percent of expected levels. The favourable weather conditions allowed reservoirs to remain comfortable and supported increased agricultural activity.
Tamil Nadu Seeks Assured Water Release
Improved storage last year encouraged farmers in Tamil Nadu to expand Kuruvai paddy cultivation substantially. Officials noted that the cultivated area increased by more than 50 percent compared to the previous season, crossing six lakh acres in 2025.
In contrast, water shortages during 2024 had reduced cultivation to below four lakh acres. The average Kuruvai cultivation area generally remains around 4.5 lakh acres.
During the recent meetings, Tamil Nadu officials reiterated their demand for Karnataka to release 9.19 TMC of water during June in accordance with the Cauvery Water Disputes Tribunal award, later modified by the Supreme Court.
Karnataka representatives, however, argued that Tamil Nadu has often consumed more water than the quantity allocated under the existing arrangement. They also maintained that tribunal allocations were framed for normal rainfall years and may not fully apply during periods of water distress.