If the rains persist, this could be the first time in 21 years that the reservoir of Mullaperiyar dam reaches its full capacity in the month of July.
Interestingly, this could coincide with the SC’s final hearing of the TN-Kerala water dispute. The reservoir, with a maximum water level of 136 ft, recorded 124.2 ft on Friday. Last year on the same day, the level was 114.1 ft. The reservoir can accommodate 6.112 TMC of utilisable water, while the water storage level on Friday was 3.46 TMC, which is 57 per cent of the total storage. The inflow to the reservoir is 1,825 cusecs of water while Tamil Nadu continues to take 1,372 cusex water (around 86 per cent of the maximum possible quantity which can be taken). If the rainfall continues like this, reservoir may soon reach its full capacity, said experts.
Last month there was 540 mm of rainfall, which was significantly high from June 24 to 27. As much as 72 mm and 58 mm was recorded on two days. Last week the average daily rainfall was 17-18 mm. The water level has been fluctuating around 124 ft for the past couple of days and peaked on June 29, touching 124.9 ft.
“Going by the trend of rainfall, there’s a high probability for the reservoir to spill over this July. Now, Tamil Nadu has been taking maximum possible water from the reservoir. There’s an equilibrium between the inflow and outflow. Yesterday, there was only 11 mm of rainfall. Once rainfall goes above 50 mm, the equilibrium will break and water may spill over”, said James Wilson, member of the Mullaperiyar Special Cell. TN has been taking water from the reservoir to Vaigai dam, which has a total capacity of 6.091 TMC.
The current level is 1.754 TMC(28.8 per cent). “There’s enough room at Vaigai to store water taken from here. Hence TN will continue to take as much water as possible”, experts said. After the new water level was set in 1979, the reservoir reached full capacity 13 times. Only twice did it occur in July - 1989 and 1992. Final hearing of the dispute between TN and Kerala has been posted before the the SC on July 23.