The researchers studied how different structures affect the Euphrates River's flood capacity in Annassiriyah City, Iraq. By using special software, they found that removing one structure could increase the river's capacity to handle floods up to 1300 m³/s. However, keeping the structure in place would limit the river's capacity to 600 m³/s. This means that without removing this structure, the river won't be able to handle a flood as severe as one that happens once every 100 years.