2018 Kerala floods


On 16 August 2018, severe floods affected the south Indian state Kerala, due to unusually high rainfall during the monsoon season. It was the worst flood in Kerala in nearly a century. Over 483 people died, and 140 are missing. About a million people were evacuated, mainly from Chengannur, Pandanad, Edanad, Aranmula, Kozhencherry, Ayiroor, Ranni, Pandalam, Kuttanad, Malappuram, Aluva, Chalakudy, Thrissur, Thiruvalla, Eraviperoor, Vallamkulam, North Paravur, Chellanam, Vypin Island and Palakkad. All 14 districts of the state were placed on red alert. According to the Kerala government, one-sixth of the total population of Kerala had been directly affected by the floods and related incidents. The Indian government had declared it a Level 3 Calamity, or "calamity of a severe nature". It is the worst flood in Kerala after the great flood of 99 that took place in 1924.
Thirty-five out of the fifty-four dams within the state were opened, for the first time in history. All five overflow gates of the Idukki Dam were opened at the same time, and for the first time in 26 years 5 gates of the Malampuzha dam of Palakkad
were opened. Heavy rains in Wayanad and Idukki have caused severe landslides and have left the hilly districts isolated. The situation was regularly monitored by the National Crisis Management Committee, which also coordinated the rescue and relief operations.

Causes

Kerala received heavy monsoon rainfall, which was about 116% more than the usual rain fall in Kerala, on the mid-evening of 8 August, resulting in dams filling to their maximum capacities; in the first 48 hours of rainfall the state received of rain. Almost all dams had been opened since the water level had risen close to overflow level due to heavy rainfall, flooding local low-lying areas. For the first time in the state's history, 35 of its 54 dams had been opened. The deluge has been considered an impact of the global warming.
A report by Jacob P. Alex, an amicus curiae appointed by the Kerala high court, said the devastating floods of 2018 was the result of bad dam management by the, state government. All 79 dams in the state were maintained with the objective to generate hydroelectricity or irrigation and controlling flood wasn't their purpose, amicus curiae Jacob P Alex's report highlighted. "The major concern of the dam operators was to maximise reservoir levels, which conflicted with the flood control purpose for which the dams could be utilised. The 'flood cushion' of reservoirs – the storage space earmarked in dams to absorb unanticipated high flows – needed review as per the latest guidelines," Alex wrote in his report. "Sudden release of water simultaneously from different reservoirs, during extreme rainfall aggravated the damage,"it said adding that various alerts —blue, orange and red—had been issued not in accordance with the EAP guideline. "No proper follow-up action and effective precautionary steps were taken after issuance of Red Alert," it said. However, Honorable high court of Kerala cleared on 20 August 2019 that the amicus curiae report is not accepted and court cannot be used for political battles and arguments.
The Government of Kerala argued in the Supreme Court that the very sudden release of water from the Mullaperiyar Dam by the Tamil Nadu government was one of the reasons for the devastating flood in Kerala. The Tamil Nadu government rejected the argument, saying that Kerala suffered the deluge due to the discharge of excess water from 80 reservoirs across Kerala, spurred by heavy rains from within the state; It also argued that the flood surplus from the Idukki dam is mainly due to the flows generated from its own independent catchment due to unprecedented heavy rainfall, while the discharge from Mullaperiyar dam was significantly less. Though it is difficult to attribute any single event to climate change, its possible role in causing the heavy rainfall event over Kerala cannot be ruled out.

Impact

Over 483 people died, and 140 are missing, while The Economic Times reported that 33,000 people were rescued. The Kerala State Disaster Management Authority has placed the state in a red alert as a result of the intense flooding. A number of water treatment plants were forced to cease pumping water, resulting in poor access to clean water, especially in northern districts of the state.
Over 3,274 relief camps have been opened at various locations to accommodate the flood victims. It is estimated that 1,247,496 people have found shelter in such camps. The flooding has affected hundreds of villages, destroyed an estimated of roads and thousands of homes have been damaged or destroyed. The Government cancelled Onam celebrations, and the allocated funds have been reallocated to relief efforts.
On 12 August, Cochin International Airport, India's fourth busiest in terms of international traffic, and the busiest in the state suspended all operations until 29 August, following runway flooding. All schools throughout the state except Sainik School Kazhakootam have been closed, and tourists have been dissuaded or banned from some districts due to safety concerns. Kochi Metro was closed briefly on 16 August, and later offered free service to aid those affected by the flooding. Due to heavy rain and rising water levels the southern railway had suspended train services on the Thiruvananthapuram-Kottayam-Ernakulam and Ernakulam-Shoranur-Palakkad sections.

Rescue

Rescue operation at government level

Being instructed by ISRO the Cabinet Secretary, senior officers of Defence Services, NDRF, NDMA and secretaries of Civilian Ministries conducted meetings with Kerala Chief Secretary. Following the decisions taken during these meetings, the Centre launched massive rescue and relief operations. In one of the largest rescue operations 40 helicopters, 31 aircraft, 182 teams for rescue, 18 medical teams of defence forces, 90 teams of NDRF and 3 companies of Central Armed Police Forces were pressed into service along with over 500 boats and necessary rescue equipments.

Rescue Operation at by Public

WhatsApp groups sprung up as Control Centers that coordinated help and support across various areas. A good majority of the population were involved in arranging supplies and help material in various ways.

Rescue operation by fisherman

According to the government's estimate, a total of 4,537 from the fishermen community participated in the rescue operation with 669 fishing boats. They managed to rescue more than 65,000 people from various districts. P. Vijayanagar honoured the fishermen and the Fisheries Minister J. Mercykutty Amma said that the government will provide financial aid to repair the fishing boats which were partially damaged in the rescue operations while new ones will be provided for those boats which were completely destroyed. According to estimates, seven boats were completely destroyed, while 452 were partially destroyed.

Animal rescues

Sally Varma of Humane Society International arranged for animals to be rescued and transported to special shelters that housed affected animals. Social media has been used to highlight the rescue of multiple animals - dogs, cats, goats, cows, cattle, ducks and snakes, with animal food and medicine transported to affected areas.
A worker with the Humane Society International spoke out against the tethering and leaving of pets that occurred. "That became a problem. So many tethered animals just drowned. These animals are natural swimmers, and it is better to keep them free so they can swim to higher ground." According to government records more than 8,000 cattle, calves and buffaloes, 3,297 goats, and 47 dogs have died due to the flooding.
The District Collector of Malappuram, and its Chief of Police have instructed the police force to save any animal that they encounter during rescue operations.

Relief and monetary aid

Government, NGOs and NPOs

Corporate and Individuals

At a press conference on 11 August, Chief Secretary Tom Jose said, "Things are well under control. The government is on top of the situation." Prime Minister Narendra Modi conducted an aerial survey and offered federal support to Keralites. Chief Minister Pinarayi Vijayan described the floods as "something that has never happened before in the history of Kerala" and placed some of the blame on neighbouring Tamil Nadu for releasing excess water from the state-operated Mullaperiyar dam, which worsened the situation.

International

The United States embassy urged its citizens to avoid traveling to the affected areas. The UAE embassy in India issues warning for its citizens regarding the flood. The embassy also said that the weather agencies in India have given warnings regarding heavy rainfall in the southern state of Kerala. The President of UAE Sheikh Khalifa bin Zayed Al Nahyan has instructed the formation of a national emergency committee to provide relief assistance to people affected by flash floods in the Indian state of Kerala.
There was a controversy regarding an offer of US$100 million from the Government of the UAE. The news about UAE aid started to spread with a tweet from CMO Kerala. "CM Pinarayi Vijayan informed that the United Arab Emirates will provide Kerala an assistance of ₹700 Crore. Kerala has a special relationship with UAE, which is a home away from home for Malayalees. We express our gratitude to UAE for their support. #KeralaFloodRelief". Normally the aid news will be announced by the government officials of the country which is offering the aid. Ministry of External Affairs of India clarified that they received no such offer for financial help from any country. The UAE Ambassador to India also declared that, officially, there was no announcement on donation to the State of Kerala.

Rainfall Data

Rainfall departures

Week by week departures from normal:

Cumulative rainfall by district

Percentage increase in rainfall compared to normal.

Analysis by Central Water Commission

Kerala as a whole

According to a study by the Central Water Commission, the average cumulative rainfall of 3 days from 15 to 17 August 2018 was about 414 mm. This was almost of the same order as that of rainfall of Devikulam which occurred during 16-18 July 1924. Assuming a runoff coefficient of 0.75, the runoff generated by 3 days of intense rainfall was estimated to be 12057 MCM for the entire state of Kerala. This huge runoff was beyond the carrying capacity of most of the rivers in Kerala, resulting in bank overflows from most of the rivers.
The total catchment area tapped by dams in Kerala, excluding barrages is about. The runoff generated from the catchment tapped by these dams during the period 15-17 August 2018 was estimated at 2.19 BCM, out of a total runoff of 12 BCM for the whole of Kerala. As per the study, with a total live storage in the state of 5.8 BCM and assuming a live storage availability of 20% on 14 August 2018, the extent of available flood moderation would have only been 1.16 BCM against an estimated inflow of 2.19 BCM. It was therefore essential to make releases from the reservoirs.
The study stated that the dams in Kerala neither added to the flood nor helped in reduction of flood, as most of the dams were already at or very close to FRL on 14 August 2018. Even if the reservoirs had been a few feet below FL, the flooding conditions would not have changed much as the heavy rainfall continued for 3-4 days. It would have been necessary to release water from the reservoirs after the first day of heavy rainfall.
The study concluded it would be necessary to review the rule curves of all reservoirs in Kerala, especially those with a live storage capacity of more than 200 MCM. This would help to create a dynamic flood cushion for moderating floods.

Periyar Basin

During the time period of 3 days from 15 to 17 August 2018, the rainfall depth realized in the Periyar basin was 588 mm. The maximum discharge passing through the Periyar at Neeleshwaram was 8800 cumecs recorded at 16 August 15:00 hrs, as per the CWC's Neeleshwaram G&D site. The major storage reservoirs in the Periyar basin are the Idukki reservoir and the Idamalayar reservoir. The peak release on 16 August 2018 from the Idukki reservoir was 1500 cumecs against an inflow of 2532 cumecs, thus achieving a flood moderation of 1032 cumecs. The release from Idamalayar on 16 August 2018 was 963 cumecs against an inflow of 1164 cumecs.
The discharge at Neeleshwaram on 17 August 2018 was 8600 cumecs. The release from Idukki and Idamalayar reservoirs were 1500 cumecs and 1272 cumecs. CWC's analysis found that the releases of water were controlled releases as the discharge capacity of Idukki and Idamalayar dams are 5013 cumecs and 3012 cumecs, respectively.

Immediate drought after the flood

A few days after receiving one of the highest rainfalls in a century, Kerala was caught under the threat of severe drought. Water level in wells, ponds and rivers have recorded lowest levels and some wells even collapsed. Chief minister Pinarayi Vijayan has directed the State council for Science, Technology & Environment to carry out studies on the phenomenon after floods across the state and suggest possible solutions to the problem.
A.B. Anita, executive director, Centre for Water Resource Development Management, an autonomous research institution under the State government, said heavy run-off of the top soil in the upland areas and the siltation in the rivers were the reasons for the falling water level. The top soil in the hills and upland areas had been removed in the flash floods to a depth of up to two metres in many places. As the top soil was shaved off, it ruined the hills' capacity to sponge in rainwater, she said. Ms. Anita cited ecological destruction caused by deforestation, harmful land use in the upland areas and sand mining in the streams and rivers as having contributed to the top soil run-off and siltation. This was exacerbated by the impact of climate change at the macro level.
Echoing her views, experts at the National Institute of Technology, Calicut, said it was usual for the water level in the rivers and domestic wells to fall after fluvial floods. "Normally, a river flows through the sand of its own bearing till the mouth. However, this time the discharge has been full, taking the sand and the rocks in the youth-stage along with the floods. So the water level in the rivers comes down. And when the river water level is reduced, the groundwater table also does not get replenished since the rivers and groundwater table are connected," said K. Saseendran, geologist and professor at the NIT-C.