The 2020 Karachi floods () were the worst flooding Karachi had seen in almost a century, and killed at least 41 people across Pakistan. The floods were caused by record monsoon rains, which were inadequately drained by poorly maintained drainage systems in the city. The resulting floods caused deaths and destruction of infrastructure and properties in the city. Background and Details of the 2020 Karachi Floods Flood Events in Pakistan Flooding is Pakistan's most threatening natural disaster. There have been eight floods in Pakistan in the last two decades. Common Causes of Flooding in Pakistan The frequency of floods has been increasing over time. The causes of floods can be divided into factors affecting rainfall, and factors affecting water retention, such as drainage and deforestation. Climate change is the primary cause of the increasing trend in flooding frequency and severity in Pakistan. 2020 Karachi Floods It has been the worst flooding since 1931 in Karachi, killing at least 41 people and leaving hundreds of thousands trapped. The record monsoon rains with inadequate drainage systems in the city caused this flood. The heavy rainfalls shattered all-time records for rainfall in a single day and other records. During August 2020, 484 mm of rain fell and was the highest amount of rain in August back to 1931. The rainfall for a single day set a new record of 223.5 mm, surpassing the previous high of 211.3 mm set in 1967. Landslides, infrastructure damage, and traffic jams caused by the floods disrupted the daily lives of around 15 million residents. Urban Conditions in the Flood Flooding engulfed the city, Karachi, bringing everything to a halt. There was a devastating damage to public infrastructures (such as broken electricity cables) and private properties (such as buildings collapsed). These damages also brought about a series of subsequent crises, with eight people dying in Karachi as a result of a wall collapse. Causes of the Floods Deterioration of Drainage Channels The damage of drains in Karachi, called nalas (such as Gujjar Nala) has been severe in recent years. Residents buy solid waste and compact it along nalas to protect their homes and this move reduces the width of the nala. In addition, since the only two landfills in Karachi are far from the eastern city, lots of non-recyclable materials are thrown in to nalas. As the development plan of Karachi was not implemented, the pressure of insufficient