Drowning is death caused by suffocation in water or other liquid. Most drownings and near-drownings happen in water to people who did not intend to enter the water, such as people who go boating. Falling into cold water is particularly dangerous. A person who becomes submerged in cold water can be quickly overcome by extremes of cold. Even shallow water can be a danger. Children have drowned in wading pools and even in bathtubs. In the United States, several thousand people drown each year.