Waterlogged roads at South Railway Station in Ernakulam following heavy rains
| Photo Credit: H. Vibhu

The northeast monsoon has kicked in early this year, and at least four days sooner for the second year running, over Tamil Nadu. Last year, this phase of the monsoon ended with the State recording 33% more rain than the long-period average, and forecasters expect this year to go the same way as well.

Historically, policymakers and State authorities have consistently interpreted excess rain as a positive. Climate change is complicating this calculus because while rainfall volumes increase, they’re often concentrated in short and localised bursts, delivering over-large quantities of water in places that often can’t absorb them in full. As a result, it might be time to reconsider the idea that “excess is good”.

In urban areas, surfaces paved with concrete and asphalt keep them from absorbing heavy rainfall, leading to rapid runoff that overwhelms drainage systems, leading in turn to flash floods, low-lying areas being inundated, damage to property, and disrupted transportation. As during Cyclone Michaung and Tamil Nadu in 2023, urban power authorities are also prone to cutting power supply in such circumstances citing loose cables. The sheer volume of water can also lead to sewage overflows, where untreated wastewater is discharged into streets and waterbodies, unleashing significant health and environmental hazards.

The agricultural sector’s vulnerability to excessive rainfall is well-known: waterlogged soil suffocates plant roots, washes away seeds and young crops, sheds the nutrient-rich topsoil over time, and ultimately loses its long-term fertility. Too much moisture can also ease the spread of fungal diseases and pests that devastate crops and undercut yield, leading to significant financial losses for farmers. Intense bursts can also wash fertilizers, pesticides, and other agricultural debris into waterbodies, including reservoirs, degrading water quality. Finally, stagnant water becomes a breeding ground for mosquitoes, increasing the risk of vector-borne diseases such as malaria and dengue fever and zoonotic diseases like leptospirosis, Japanese encephalitis, and scrub typhus.

Prolonged periods of rainfall also raise the water table, which is the level below which the ground is saturated with water. And a persistently high water table can compromise the stability of building foundations, roads, and other infrastructure; it can also exert pressure on basement walls, leading to cracks, leaks, and the growth of mold. Saturated soil also loses its load-bearing capacity and causes foundations to shift or settle, potentially leading to significant structural damage over time.

The cumulative impact of these issues translates to significant economic and social costs. Damage to buildings, public infrastructure, and agricultural land warrants substantial investments in repair and rebuilding solutions. Disruptions to businesses and transport networks hamper economic activity. Flooding and landslips can also displace communities, injure people, and even kill them if they’re particularly vulnerable. The psychological toll on affected populations, including stress and anxiety, is another significant, and often overlooked, consequence.

Tamil Nadu in particular needs to consider the Kerala factor as well. The two States receive rain from two different monsoon patterns: Kerala’s primary rainy season is the southwest monsoon from June to September whereas Tamil Nadu receives most of its rain during the northeast monsoon from October to December. An important problem arises when these monsoon periods overlap or when both States experience intense rainfall simultaneously. This is currently the case with the early onset of the northeast monsoon.

At the heart of the issue is the Mullaperiyar Dam, which, while it’s located in Kerala’s Idukki district, is operated by the Tamil Nadu government to divert water to irrigate farmland in Theni, Madurai, Dindigul, and other districts. There is as a result a ‘direct’ link between the rainfall in Kerala’s catchment areas and the water levels in Tamil Nadu’s river systems.

When the catchment areas of the Mullaperiyar Dam receive heavy rainfall, the reservoir fills up rapidly. To ensure the dam’s safety and to manage the rising water levels, Tamil Nadu’s authorities are compelled to open the dam’s shutters, releasing a significant volume of water downstream. The released water flows in two directions and risks creating a double whammy. One portion flows down the Periyar River within Kerala, potentially flooding the low-lying areas of Idukki district and creating an inter-State issue while the primary flow is diverted to Tamil Nadu’s Vaigai Dam. And this influx may arrive precisely when Tamil Nadu’s own rivers and reservoirs are already swollen from the ongoing northeast monsoon.

This simultaneous influx thus turns Kerala’s “excess” water from a potential resource into an immediate flood risk for Tamil Nadu. Instead of just managing the rainwater falling within its own borders, Tamil Nadu must also handle a massive, concentrated inflow from its neighbour. The State is currently keeping all 13 shutters of the Mullaperiyar Dam open, releasing thousands of cusecs of water in order to make room for the incessant influx. As a result, both farmland and residential areas in Theni are already submerged even as the district is being battered by its own monsoon rains.

For these reasons, it may be time for Tamil Nadu and other States like it, including Kerala, to reconsider the “excess is good” notion vis-à-vis rainfall.

Published – October 20, 2025 02:17 pm IST

Washington:

US President Joe Biden and First Lady Jill Biden expressed condolences to India over the devastating landslides in Kerala’s Wayanad that took the lives of over 300 people.

“Jill and I extend our deepest condolences to all those affected by the deadly landslides in the state of Kerala in India,” the White House said in an official statement.

“Our prayers are with the victims of this tragic event, and we mourn with the families who have lost loved ones. We commend the bravery of the Indian service members and first responders supporting the complex recovery effort. We will continue to hold the people of India in our thoughts during this difficult time,” said the White House.

The number of people who died in the landslides that struck the hilly areas of Meppadi in Wayanad district on July 30 following incessant rainfall has gone up to 210 while the people who have been discharged from the hospitals stood at 187, officials said on Friday.

As per the officials, 210 bodies and 134 body parts have been recovered till now which includes 96 males, 85 females and 29 children.

The number of bodies identified by relatives stood at 146. The administration has completed the post-mortem of 207 bodies and 134 body parts found from the incident site.

According to the officials, 84 people are undergoing treatment in various hospitals in Wayanad, Kozhikode and Malappuram districts while 187 have been discharged.

273 people have been brought to hospitals from the incident site.

Earlier today, Kerala Health Minister Veena George confirmed 308 deaths in the multiple landslides that hit Wayanad on July 30.

Two massive landslides hit Wayanad’s Chooralmala and Mundakkai on July 30 creating widespread devastation, and loss of lives and property in the region.

(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)

The India Meteorological Department (IMD) has warned that a weather system over the Indian Ocean would cause heavy rains in Kerala for the next 48 hours. 
| Photo Credit: S. MAHINSHA

Rain-related accidents claimed at least three lives in Kerala on July 16. Reports of power outages caused by tree branches falling on supply lines, inundated roads, rising river water levels, minor mudslips, and a few house collapses were trickling in from across the State. 

Sulochana, 54, and her son, Ranjith, were killed when their tumbledown single-room house collapsed on them while sleeping at Kannambra in Palakkad district. The Fire and Rescue Services department removed their bodies to the district hospital for post-mortem examination. Sulochana was bedridden, and Ranjith worked as a private bus conductor.

In Kannur, Kunhamina, 51, drowned after she fell into an open well. In Mattannur, Kannur, neighbours rescued a woman trapped inside her partially collapsed house.

In Mananthavady in Wayanad, heavy rains and slippery roads caused a KSRTC bus to veer off the carriageway. The passengers and the bus crew escaped unhurt. 

A mudslip partially choked the Munnar-Mattupetty road, slowing traffic on the arterial inter-State route. 

Dam shutters raised

Authorities have raised the shutters of the Peringalkuthu and Malankara dams and cautioned people living downstream to exercise utmost vigilance. 

In Thiruvananthapuram, district authorities have raised the shutters of the Peppara and Aruvikkara dams following heavy inflow from the catchment areas into the drinking water reservoirs.

Floodwaters have swamped the iconic Shiva Temple at Aluva in Ernakulam.  

The India Meteorological Department (IMD) has warned that a weather system over the Indian Ocean would cause heavy rains in Kerala for the next 48 hours. 

It has declared an orange alert for Malappuram, Kozhikode, Wayanad, Kannur, and Kasargode districts on July 16 (Tuesday). The IMD has also placed Idukki, Pathanamthitta, Alappuzha, Ernakulam, Thrissur, and Palakkad districts under the yellow alert category.

Revenue Minister K. Rajan said the government had opened control rooms and relief camps in worst-hit taluks.

Thiruvananthapuram:

Schools and colleges will remain closed on Thursday in six districts in Kerala in view of the rain alert issued by the India Meteorological Department (IMD) for the state.

The districts that have declared the holidays are Pathanamthitta, Kottayam, Alappuzha, Idukki, Ernakulam and Wayanad.

Meanwhile, all the professional exams which are scheduled for the day will not be cancelled.

Some districts of Kerala have been receiving incessant rainfall for the last two days.

The Regional Met Centre of Thiruvananthapuram has issued an orange alert for the districts of Wayanad and Kannur, while a yellow alert has been issued for the districts of Kasaragode, Kozhikode, Malappuram, Palakkad, Thrissur, Idukki and Ernakulam.

Earlier on Wednesday, an orange alert was issued for eight districts, including Wayanad, Kannur, Kasaragode, Kozhikode, Idukki, Ernakulam, Pathanamthitta, and Thiruvananthapuram.

The IMD has also predicted heavy to very heavy rainfall, very likely along the West Peninsular Coast during the next 3-4 days and over northeast India, likely from June 27 to June 30. The rainfall activity is likely to increase over Northwest India, with heavy to very heavy rainfall likely from June 28 to June 30.

On advancement of southwest monsoons, the IMD said in a press release, “The Northern Limit of Monsoon continues to pass through Mundra, Mehsana, Udaipur, Shivpuri, Siddhi, Lalitpur, Chaibasa, Haldia, Pakur, Sahibganj, and Raxaul. Conditions are likely to become favourable for further advance of Southwest Monsoon into the remaining parts of North Arabian Sea, Gujarat State, Madhya Pradesh; some more parts of Rajasthan; remaining parts of Chhattisgarh, West Bengal, Jharkhand, and Bihar; most parts of East Uttar Pradesh; some more parts of West Uttar Pradesh; some parts of Uttarakhand, Himachal Pradesh, Jammu-Kashmir-Ladakh-Gilgit-Baltistan-Muzaffarabad, northern parts of Punjab and northern parts of Haryana during next 3-4 days.”

(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)

Thiruvananthapuram:

As Kerala reels under the impact of heavy pre-monsoon rains, a total of 11 people have lost their lives in various rain-related incidents across the state since May 19.

As heavy rains continue to lash Kerala, the India Meteorological Department (IMD) today issued an orange alert in eight districts in Kerala for Friday.

According to the Kerala State Disaster Management Authority, 15 houses across the state fully collapsed while 218 were partially damaged in the heavy rains.

The IMD has issued an orange alert in Thiruvananthapuram, Pathanamthitta, Alappuzha, Kottayam, Ernakulam, Idukki, Kozhikode and Kannur districts and a yellow alert in other districts.

A red alert indicates heavy to extremely heavy rain of over 20 cm in 24 hours, while an orange alert denotes very heavy rainfall of 11 cm to 20 cm, and a yellow alert means heavy rainfall between 6 cm and 11 cm.

State Revenue Minister K Rajan had earlier in the day informed the public that parts of the state had received over 200 mm of rain in the last 24 hours.

Rajan, who met the media today, said parts of Kerala received over 20 cm of rain in the last 24 hours and added that a total of 11 people have lost their lives in the state in various recent rain-related incidents.

“Six persons lost their lives in various drowning incidents, two fell into water-filled quarries, two were struck by lightning and one person lost his life in a wall collapse,” he said.

Kunnamangalam in Kozhikode district received 22.62 cm of rain in the last 24 hours, the minister added.

Cherthala in Alappuzha district received 21.5 cm rain, Kumarakom in Kottayam district and Thamarassery in Kozhikode district received 20.3 cm and over 20 cm rain respectively in the last 24 hours, the Minister added.

“Such heavy rainfall in a short span of time will lead to various incidents and we need to arrange facilities accordingly,” Rajan said.

He said the local authorities, Fire force, the police and Revenue department were ready to face any untoward incidents. The minister also said two teams of the NDRF were currently in the state.

Parts of Kochi city were inundated during the day following heavy rains last night.

Similar was the situation in nearby Aluva town on Friday morning where the market was waterlogged.

Local residents have alleged that the Aluva Municipality failed to clean the drainage resulting in the heavy waterlogging.

Reports of trees being uprooted, road damage and minor landslides were reported from various parts of the state.

Currently, 223 people have been accommodated in eight relief camps functioning across the state.

The relief camps were opened in Kozhikode, Malappuram, Ernakulam and Thiruvananthapuram districts in view of the heavy rains.

In wake of the incessant rains, a state control room was set up in the Health Department Directorate at Thiruvananthapuram on Wednesday as part of efforts to strengthen epidemic prevention activities.

(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)

In the 24 hours ending at 8.30 a.m. on May 20, most districts in Kerala reported rainfall. A scene in Thiruvananthapuram on May 19.
| Photo Credit: S. MAHINSHA

Four districts in Kerala continue to be on red alert for extremely heavy rainfall on May 20, although no untoward rainfall-related incidents have been reported so far in the State.

As per the latest weather forecast from the India Meteorological Department (IMD), the districts of Idukki, Kottayam, Pathanamthitta and Alappuzha continue to be on red alert for extremely heavy rainfall (above 20 cm in a 24-hour period).

Idukki has been receiving steady rainfall since May 20 morning. Pathanamthitta and Kottayam have not reported heavy rainfall so far on the day. The Pathanamthitta district administration has banned travel to the Gavi hill station in view of the IMD warning. Alappuzha also has reported moderate rainfall so far.

Orange and yellow alerts

Thiruvananthapuram, Kollam and Ernakulam are on orange alert on May 20 for isolated heavy to very heavy rainfall. The remaining seven central and northern districts are on yellow alert for isolated heavy rainfall.

The next IMD update is expected at 1 p.m.

In the 24 hours ending at 8.30 a.m. on May 20, most Kerala districts reported rainfall. Kollam and Laha in Pathanamthitta district reported heavy to very heavy rainfall of 19 cm, Chakka in Thiruvananthapuram 16 cm, Thiruvananthapuram airport 13 cm and Aralam in Kannur 11 cm.

The Kerala State Disaster Management Authority, citing an IMD Nowcast, said Thiruvananthapuram, Palakkad, Alappuzha and Ernakulam should brace for heavy rain in the next three hours.

Earlier this year, as the summer monsoons struck the country, Bengaluru, Gurugram, and Mumbai were quickly under several feet of stagnating water. Similar scenes played out in settled areas in many parts of the country, with officials evacuating several thousand people in anticipation of floods.

India’s urban areas have been flooding more and more often. These urban floods lead to life and livelihood loss, and can push governments into economic crises. In July this year, a State Bank of India report estimated the economic loss due to the 2023 North India floods and Cyclone Biparjoy in Gujarat together to be Rs 10,000-15,000 crore.

Now, a new study, published in Nature journal on October 4, and led by the World Bank, has found that these risks have been exacerbated by the rapid and continuous expansion of cities into areas at high risk of flooding. According to its authors, since 1985, human settlements in flood-prone areas have more than doubled in the last four decades.

Urban settlement experts said the findings reiterate the risk of unsustainable urbanisation in India while highlighting the urgent need to account for flood-related risks in how urban expansion is planned and executed.

Exposure to flood risk

The study used satellite data to determine global flood patterns and compared it against high-resolution global maps of expanding urban settlements. The researchers found that worldwide, East Asia had the highest rate of settlement expansion in flood-prone areas versus those that are flood-safe. Sub-Saharan Africa and North America on the other hand had the least expansion into flood-prone areas.

The study also found that middle-income countries have more urban settlement in flood-prone zones than that in low- and high-income countries. In the World Bank’s estimate, India is a low-middle-income country (or LMIC).

On the upside, India isn’t among the 20 countries whose settlements are most exposed to flood hazards. Its neighbours Bangladesh, Bhutan, China, and Myanmar are. But the study found India to be the third highest contributor to global settlements, after China and the U.S., and also third – after China and Vietnam – among countries with new settlements expanding into flood-prone areas (all in 1985-2015).

Gautam Bhan, a researcher who studies urban settlements at the Indian Institute of Human Settlements (IIHS), Bengaluru, interpreted this to mean India stands at significant risk of flood-related problems that could worsen considerably in the coming years if the country wasn’t careful.

However, Raj Bhagat Palanichamy, a geoanalyst at WRI India, said the data in the study – from a database called EM-DAT – may not have the “granularity required for studying flood-prone areas in our urban areas and peri urban areas.” 

That is, since the database is a large record of mass disasters and not a “flood-plain record”, Mr. Palanichamy said “the data are still not comprehensive enough to assign ranks to countries based on their settlements’ exposure to floods.”

Urbanisation and flooding

In 2022, ecohydrologist Jagdish Krishnaswamy and remote sensing specialist Kiran M.C. from the IIHS wrote in The Hindu that climate change is worsening monsoons in India by increasing the rate of evaporation from oceans, increasing moisture content in the atmosphere, and creating more cyclonic storms in the water bodies surrounding India. The end result is that floods are frequent.

At the heart of flood-related hazards is “where we build or expand our cities,” Mr. Palanichamy had written in 2022.

He had estimated that the Bengaluru floods in 2022 cost the city Rs 225 crore. Between 1901 and 2022, the city’s population is estimated to have grown from 1.6 lakh to more than a crore. To accommodate these people, the city expanded. However, new localities overlooked the city’s “topography”, Mr. Palanichamy had added.

This led to urbanisation of flood-prone areas as well as the creation of new risks, Dr. Bhan said.

For example, as construction began in the “valleys and ridges” of Bengaluru – inherently low-lying areas and flood-prone – the increasing concrete cover reduced the amount of rainfall that could percolate the soil, the duo explained. The new structures also impeded the flow of water into canals, increasing the probability and intensity of floods.

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Disproportionate risk by class

Mr. Palanichamy and Dr. Bhan both said that expanding urbanisation in flood-prone areas is a story of both the elite and the poor. Dr. Bhan provided the Yamuna floodplains as an example, with its three kinds of settlements: “informal settlements, government structures, and unauthorised colonies.” 

They also added that the risks were disproportionately higher for those living in informal structures. According to Dr. Bhan, “The geography of environmental risk is also the geography of informal low-income housing.”

He added that if one had to build informal housing in the city, they would need to “occupy land that is vacant and slightly less desirable, so that they are not immediately driven off.” So informal settlements often lie in “low-lying, flood-prone areas”.

Not locality-level issues

According to Dr. Bhan, an important reason why urbanisation has expanded into flood-prone areas specifically, and in “ecologically unsustainable areas” generally, is that “we don’t have the governance processes to say, ‘Look, this kind of development is environmentally unsustainable.’”

He added that when environmental regulations are applied to new constructions, they are often applied only to big infrastructure projects and not to medium- and small-scale modifications of localities.

This contradicts the observation that certain localities are more flood-prone than others, and that flooding and flood-risk are locality-level issues.

In the 2022 Bengaluru floods, for example, R.M.Z. EcoSpace in the Outer Ring Road and the Rainbow Drive in Sarjapur Road 5 km away were equally affected. And both, according to Mr. Palanichamy, are plagued by heavy construction activity.

Dr. Bhan added that people commonly violate existing government regulations. He invoked the examples of a rise in eco-tourism resorts on forest land and the construction of large public structures, including government buildings and even religious structures, on rivers’ floodplains.

Earlier this year, The Hindu reported on the construction of the Akshardham Temple on the Sabarmati riverfront, as a result significantly narrowing the river and increasing the risk of floods in neighbouring areas.

Protect low-income housing

As cities and their populations continue to expand, Mr. Palanichamy and Dr. Bhan cautioned that we can no longer avoid expanding into flood-prone areas. “Market forces tend to push expansion into flood-prone areas,” said Mr. Palanichamy. “But recognising what these areas are and that we are actually expanding into them is the first step towards sustainable urban planning that addresses the resulting risks.”

Some forms of adaptation are necessary, said Dr. Bhan, and they need to differentiate between low-income residents and unauthorised structures erected for the elite.

“Every city needs to do a proper scientific mapping of the flood prone areas,” Mr. Palanichamy said. He also suggested that better storm-water management plans have to be put in place – including more “storm-water drains that collect and divert rainwater” being installed in the flood-prone areas of cities.

But Dr. Bhan said storm-water drains are only one solution; urban governments also need to make housing in such areas more resilient to floods as well as upgrade and protect low-income housing. He gave the example of riverside settlements that use stilt houses – like those used by the Mishing and the Miyah communities along the banks of the Brahmaputra.

Sayantan Datta (they/them) are a queer-trans freelance science writer, communicator and journalist. They are currently a faculty member at Krea University and tweet at @queersprings.