Water level in the Mullaperiyar reservoir near Kumili on the Kerala-Tamil Nadu border crossed 135 feet, just one foot short of the peak permissible level of 136 on Wednesday.
The rising water level in the more-than-a-century-old Mullaperiyar, which is a subject of dispute between the two States, has caused scare and anxiety among tens of thousands of people living in the vicinity of the dam as well as along the banks of the Periyar. The strength and holding capacity of the dam have been a matter of concern for several years and the Kerala government has for some time been insisting on constructing a new dam.
Though the rains in the catchment area of the reservoir were sporadic and light on Wednesday, the inflow into the reservoir was heavy because of the incessant rains in the catchment areas in past three days. The water will spill over once the level hits 136 feet and flow out through the spillway, finally ending up in the Idukki reservoir.
Meanwhile, the Idukki reservoir itself is fast getting filled up and reaching its full capacity level. On Wednesday, the water level was 2,394 feet, which is roughly 85 per cent of its capacity.
The authorities and the people living downstream fear that if the Mullaperiyar reservoir spills over, the run-off will force opening of the Idukki reservoir and letting out huge amounts of water down the Periyar. This would flood vast stretches of the thickly populated Periyar river banks and might cause destruction all the way down to the river mouth at Kochi.
Already, the letting out of water from several dams across the State following the incessant rains over the past few days has caused floods in vast areas.
The impact was felt at the Kochi international airport at Nedumbassery. The flooding in the Periyar drove water up a tributary which in turn caused a reverse flow into the drainage system of the airport, leading to the flooding of the runway and taxi bay. The airport had to be closed for a day and half and nearly 50 flights were cancelled.
Authorities said they were constantly monitoring the water levels in the Mullaperiyar and the Idukki reservoirs. Several safety measures have been taken and inhabitants in the area have been alerted.