Thiruvananthapuram: Kerala continued to reel under severe floods on Wednesday as heavy rains and landslides claimed 29 lives, taking the toll to 72 in the state.

Flight operations at the Kochi airport were suspended till Saturday as officials said a red alert had been sounded in all the 14 districts of the state.

All the rivers in the state, from Kasaragod in the north to Thiruvananthapuram in the south, are in spate and shutters of 35 dams, including Mullaperiyar, have been opened.

Chief minister Pinarayi Vijayan said the heavy rains would continue for some more days, which would further worsen the situation, even as he asked residents to limit their drinking water usage as distribution systems collapsed.

More than 1.5 lakh people have been lodged in relief camps across the state, he said.

A government release said Vijayan spoke to Prime Minister Narendra Modi and home minister Rajnath Singh on the grave situation the state was facing following the rains. The prime minister has assured all help, it said.

The prime minister has taken a "positive stand" towards the state on relief measures, Vijayan told reporters.

Train services have been disrupted and road transport services are in disarray with stretches of roads coming under water.

Officials said a holiday had been declared for educational institutions in all districts barring Kasaragod on Thursday, while colleges and universities have postponed exams.

Power supply, communication systems and distribution of drinking water have been disrupted in various parts of the state in the rain mayhem.

As the situation became grave, the state government sought the help of more teams of army personnel, National Disaster Response Force and Army Engineering.

The Navy on Wednesday rescued more than 80 persons as the flood situation worsened in Kerala again, leaving a fresh trail of death and destruction. As part of its 'Operation Madad', the Southern Naval Command deployed 21 rescue and diving teams with Gemini boats as the situation deteriorated across the southern state where 19 people lost their lives since Tuesday evening due to the incessant downpour, forcing authorities to issue a red alert.

The chief minister also met governor P Sathasivam and apprised him of the situation.

Major tourist centres, including Athirappally, Ponmudi and Munnar, which were expecting huge influx of visitors in the wake of Onam, have closed.

The Kochi international airport announced a shutdown till Saturday after water entered the airport area. As flights were being diverted to various airports or suspended, the state government decided to seek the Centre's permission to allow small aircraft to land at the naval airport in Kochi.

Airlines including IndiGo, Air India and SpiceJet have announced suspension of their operations to Kochi.

A landslide between Kuzhithurai and Eraniel stations has delayed four long distance trains, railway sources said, adding a few passenger trains have been partially hit.

There were also speed restrictions on trains on the Thiruvananthapuram-Thrissur section while rail traffic on the Kollam-Punalur-Sengottai section has been suspended.

An urgent meeting, convened by the chief minister here to evaluate the flood situation, directed officials to requisition maximum number of lifeboats from Tamil Nadu.

The chief secretary was asked to contact neighbouring states for emergency assistance.

A group of military engineering personnel are expected to arrive in Thiruvanathapuram from Pune by IAF aircraft for rescue operations.

Periyar, Chalakudy Puzha and Pampa rivers were overflowing in central Kerala, while the water level in Killiyar, Karamanayar, Vamanapuram rivers and Parvathyputhanar canal in Thiruvananthapuram district are steadily rising.

The tourist town of Munnar is virtually inundated after shutters of the Idukki, Mullaperiyar and Mattuppetty dams were opened.

With the water level in the Mullaperiyar dam touching the maximum of 142 feet, Vijayan wrote to his Tamil Nadu counterpart K Palaniswami requesting him to bring down the level to 139 feet in view of the dam's safety.

Vijayan pointed out that the catchment areas of the the reservoir were receiving heavy rain.

Rajnath Singh informed Vijayan that based on the state's request, the Union home secretary spoke to the Tamil Nadu chief secretary on release of more water from the dam to bring down the level to 139 feet.

The dam, located in Idukki district of Kerala, is owned and operated by Tamil Nadu. “There is no need for any anxiety with regard to Mullaperiyar dam, where the water level has touched 142 feet, the maximum as allowed by the Supreme Court, as the discharge is equivalent to the inflow," Vijayan told reporters.

Aluva and Paravoor in Ernakulam district, on the banks of the Periyar, are facing flood threat. Peermade in Idukki recorded the highest rainfall of 27cm on Wednesday while Idukki town received 23cm, Munnar 22cm and Karipur in Malappuram 21cm.

The meteorological department has forecast turbulent weather for Kerala.

(With PTI inputs)