The scientists studied how floods in the Young-san River, Korea are affected by changes in the environment. They used a computer model to simulate floods in 1998 and 2004. They found that not considering the storage effects of the riverine lowland caused a 1.23 m rise in water level downstream, affecting areas up to 40 km upstream. During a big flood, the peak water level rose by 59 cm compared to previous estimates. They also discovered that expanding the lock gate lowered the peak water level by 18 cm downstream. This suggests that more actions are needed to reduce water levels in the area.