While the amount of yearly precipitation in Indonesia’s capital of Jakarta has fallen, torrential rainfalls have increased, bringing about more frequent overflows of rivers. Jakarta is said to be the world’s first city likely to be submerged and it now faces disaster crises caused by a variety of factors. However, city submergence is not a problem for Jakarta alone. It has been pointed out that due to the effects of climate change, flooding from river overflows and sea level rise could take place in megacities around the world. This article is a report on the city of Jakarta.