Bangladesh is a developing country in Asia and it is frequently affected by flooding. For example, in 2007 flooding made 9 million people homeless and approximately 1,000 people died from drowning and from waterborne diseases.
Bangladesh is a very poor country and so has less money to spend on flood defences than richer countries. Most people in Bangladesh do not earn enough to pay for insurance against flooding, so when there are floods they risk losing everything.
Unfortunately, many of these long-term responses are difficult to pay for and maintain. They are not always successful and don't always help enough people.