Weather Update: Heavy Rainfall in Kerala Today, 10 Districts on Alert

With a cyclonic circulation lingering over coastal southern Tamil Nadu, the India Meteorological Department (IMD) has issued a 'Yellow' alert for 10 districts in Kerala as the state braces for more rains.

According to the IMD, the cyclonic circulation would bring extensive rainfall to Kerala in the coming days. On Friday, ten districts have been put on yellow alert: Kollam, Pathanamthitta, Kottayam, Ernakulam, Idukki, Thrissur, Palakkad, Malappuram, Kozhikode and Wayanad.

A Red alert means heavy to extremely heavy rainfall of more than 20 cm in 24 hours, while an Orange alert means very heavy rains of 11 cm to 20 cm. A yellow alert implies 6 to 11 cm of rain is expected.

The cyclonic circulation, which is likely to persist for the next two days, is also anticipated to bring heavy rainfall to the state's hilly regions, according to the Met Department.

The National Disaster Response Force (NDRF) has twelve teams stationed around the country. On standby are three Army and Defence Security Corps (DSC) teams, two IAF helicopters, and a naval helicopter.

Alert sounded in dams

In the dams of Kakki, Sholayar, Pondumi, Peringalkuthu, Kundala, Kallarkutty, Irattayar, Lower Periyar, and Peechi, a red alert has been issued. Orange alerts have been issued for the Idukki-Cheruthoni, Mattupetty, Chimmini, Chulliyar, Malampuzha, Mangalam, and Meenkara dams.

Heavy rain followed by thunderstorms and lightning, pelted various regions of Kerala on Thursday after a brief respite. 

At 10 p.m. on Thursday, the water level in Cheruthoni Dam had risen to 2398.30 ft. On Tuesday, the pressure reached 2398.08 ft., therefore three shutters were lifted as a precaution.

Meanwhile, the Mullaperiyar dam reached a height of 135.10 feet. When the water level hits 136 feet, it will flow via the spillways. The water from Mullaperiyar dam will flow via the Periyar River and reach Idukki dam if the shutters are opened.

Meanwhile, the state government has raised the rule curve for three dams under the control of the state electricity board. A rule curve, also known as a rule level, defines how much storage or empty space should be kept in a reservoir at different periods of the year.

Idukki dam's rule curve has been raised to 2399.31 feet from 2398.86 feet, while Idamalayar dam and Kakki dam's new rule curves are 167 ft. and 979.84 ft. respectively.

Based on water availability, dam capacity, and safety, the goal is to ensure maximum storage. During the rainy season, the rule curve is higher and during the summer, it is lower in proportion to the drought.

From June to November, the rule curve is raised three times a month. By the end of November, Idukki will reach a height of 1459.55 ft. Meanwhile, the Banasura Dam's rule curve will stay at 775.6 feet.