Attachments
Description of the Event
Date of event
02-06-2024
What happened, where and when?
The significant intensification of the Southwest monsoon, which began in mid-May 2024, escalated on 2 June 2024. Several areas in the Western, Southern, Sabaragamuwa, and Northwestern provinces recorded unprecedented rainfall exceeding 200 millimetres during this period. This exceptional weather event led to severe flash floods, mudslides, and substantial wind damage in the Colombo, Gampaha, Kalutara, Matara, Galle, Ratnapura, and Puttalam districts.
Key rivers, including the Nilwala Ganga in Matara, the Gin Ganga in Galle, the Kalu River, the Attanagalu Ganga in Gampaha, and the Kelani River in Colombo, experienced rising water levels, resulting in overflow. According to the Disaster Management Centre (DMC), as of 5 June 2024, more than 65,000 families residing in low-lying areas of these districts were affected.
The main impacts of the monsoon included heavy rainfall, strong winds, flooding, damage to homes and infrastructure, and the displacement of thousands of people. Agricultural lands and crops were destroyed, and access to essential goods and services was severely limited.
Vehicular movement was disrupted on major roads connecting key towns, and several coastal roads were restricted due to flooding and damage. Additionally, railway services were temporarily halted because of floodwater along the tracks.
As a result of the severe weather conditions, over 2,500 families (more than 10,000 individuals) were displaced nationwide and accommodated in 154 safety centres established by the Disaster Management Centre.
Government and Organizational Response:
The Sri Lankan government deployed relief teams, including Navy and Army personnel, to assist the flood-affected districts. These teams rescued over 102 individuals across the affected areas during the severe weather events. As a precautionary measure, electricity was cut off in up to five districts to prevent electrical shocks in flooded areas, causing many people to spend the night without power. Several flights arriving at Colombo’s main international airport were diverted to Matale airport.
The Ministry of Education announced the closure of all schools across the island on 2 June 2024. Schools in the Galle, Matara, Gampaha, and Kalutara districts closed on 3 June, and schools in the Sabaragamuwa Province closed on 4 June due to the severity of the conditions. Many schools were flooded, and students in low-lying areas lost their materials and stationery.
Meteorological Warnings:
Landslide Risks:
The severely affected districts were also at risk of landslides due to the intensified rainfall. The National Building Research Organisation (NBRO) issued landslide warnings at various levels (1 to 3) starting 2 June 2024. NBRO issued ‘Red’ (Level 3) landslide alerts for several areas in the Colombo, Kalutara, Ratnapura, and Kegalle districts. ‘Amber’ (Level 2) and ‘Yellow’ (Level 1) alerts were issued for other areas in the Southern, Western, and Sabaragamuwa provinces [02].
The Department of Meteorology warned that the Southwest monsoon had intensified significantly due to global warming and the conditions associated with La Niña. The increased intensity resulted in a greater volume of rainfall within a shorter period, marking a departure from the usual spread over a longer duration.
The rainfall intensity increased from 3 to 5 June 2024, reaching up to 100 mm per hour, attributed to changes in atmospheric wind patterns [03]. As the water levels in rivers continued to rise downstream due to runoff from higher lands, many low-lying areas were further impacted.
By August 2024, the severity of the situation had returned to normal. However, weather conditions remained abnormal, with districts continuing to experience significant rainfall.
Displacement and Relief Operations:
In June 2024, displaced individuals returned to their homes after a week, following the flash floods. At one point, high water levels in low-lying areas made it difficult for branches and volunteers to deliver relief items to affected locations. Despite the ongoing heavy rain, dengue prevention activities remained active throughout the operation.
Due to climate change, the country experienced another round of flash floods from inter-monsoon rains at the end of October 2024. This unexpected event severely impacted the country. In response, the Sri Lanka Red Cross Society (SLRCS) launched its second DREF request to support the three most affected districts at the end of October and early November 2024.
Reference Links:
[1] https://www.dmc.gov.lk/images/dmcreports/Situation_Report_on_2024__1717580244.pdf