Kerala is experiencing its worst floods in a century. 256 people have been killed and lakhs displaced since the monsoons set in on May 29. While between June 1 and August 15, the state has seen an overall average excess rainfall of 30.7%, it’s the last seven days that have been devastating. IMD data shows that, on average, the state has seen a whopping 257% more rainfall between August 9 and August 15.

To put things in perspective, during the Chennai floods in 2015, the city received 1600 mm of rainfall between October and December that year, as against its normal of 790 mm. That is, a deviation of 102%.

Data from the Indian Meteorological Department (IMD) shows that Kerala has received 2091.1 mm of rainfall between June 1 and August 15 as against the normal of over 1600 mm – an excess of 30.7%.

To understand the sheer intensity of the rainfall, it’s important to look at the rainfall in the districts.

Rainfall between August 9 and August 15

According to the Kerala government, 67 people were killed in the last seven days. The period had a state-wide average rainfall of 352 mm, as against the normal of 98.5 mm. That’s a massive 257% more than normal.

Idukki district alone has recorded 679 mm of rainfall in the past week, as against the normal of 126.3 mm – 447.6% more. Owing to the heavy rainfall, for the first time in 26 years, the shutters of Cheruthoni dam in Idukki were opened on August 9 with water levels inching towards Full Reservoir Level. According to data for the period August 8 to August 15 from the Disaster Management State Control Room, 16 people were killed and 11 injured, while 4 persons were missing in Idukki.

The hill district of Wayanad has recorded 536.8 mm of rainfall in the past week, a departure of over 400 mm. Several parts of the district are under water, after shutters of the Banasura Sagar dam and the Karapuzha reservoir were opened on August 15. According to official statistics, 4 people were killed, and 4 injured in the rains the past week.

With landslides and flash floods reported from several areas in Wayanad, officials say that 88 houses have been completely destroyed and 529 houses were partially damaged.

Neighbouring Malappuram witnessed nearly 450 mm of rainfall in seven days, a departure of over 350 mm. The district has recorded the highest deaths with the rains claiming the lives of 17 people.

In north Kerala, Kozhikode recoded 375 mm of rainfall, while Kannur received over 322 mm. Palakkad witnessed 350mm of rainfall, a departure of 267.6 mm.

August 15 rainfall

Peerade in Idukki recorded the highest rainfall in the state on August 15 with 274 mm. Idukki town witnessed 235 mm of rainfall, while the hill station of Munnar received over 216 mm on Wednesday.

According to IMD, in Malappuram’s Karipur AP, over 210 mm of rainfall was recorded, while Manjeri received 200 mm. The Cochin International Airport, which was shut on August 15 owing to the floods, received nearly 172 mm of rainfall on the same day.

Irikkur in Kannur, meanwhile, received 178 mm of rainfall, while Wayanad’s Mananthavady recorded 161 mm of rainfall on Wednesday, and Vythiri received 152 mm of rain.

Seasonal rainfall

According to IMD’s statistics, Idukki experienced the highest among rainfall this season, with an excess of over 70%. While Idukki normally receives over 1700 mm of rainfall, it has so far recorded over 2945 mm of rainfall, making it the worst-hit district in the state.

Wayanad has received 2604.6 mm of rain between June 1 and August 15, as against the normal of 2147.5 mm, a departure of 21% this monsoon.

Malappuram, that has witnessed landslides from different parts of the districts, with a couple and their child being buried alive in their house, has recorded an excess of 40% rainfall. As per data, Malappuram district has recorded over 2346 mm of rainfall so far.

Kottayam has also been battered by the rains, with the district receiving 2034 mm of rain against the normal of 1441 mm. That’s an excess of 41% in Kottayam district alone.

While Palakkad normally receives 1241 mm of rainfall – marginally less than other districts in the state – this monsoon season it recorded 57% excess or 1950 mm of rain.

Only Kasargod in the north and Thrissur district in central Kerala have recorded a normal rainfall this season.

Water levels in 35 dams continue to rise, even as officials continue to keep shutters open. A red alert has been issued in all 14 districts of the state, as heavy to very heavy rainfall has been forecast on Thursday.