Korea’s annual average precipitation is 1,245mm (124.0 billion tons), which is approximately 1.4 times the global average (880mm); but, with approximately 70% of the year’s precipitation falling during the rainy season (June to September), only 27% (33.7 billion tons) of the total rainfall can be efficiently collected and used.
Accordingly, Korea’s per capita precipitation stands at only one eighth of the global average, and, in the per capita water resources, the nation is ranked 129th at 1,453m3.
2. Frequent droughts and severe water shortages
Due to the concentration of precipitation during the rainy season, droughts last for six months of the year (October to April), causing severe water shortages across many regions. According to the Long-Term Plan for Water Resources (2006), the nation will require at least 0.8 billion tons of water in 2011 and 1.0 billion tons a year by 2016.
The nation’s per capita amount of water resource development is only 42% that of Japan and 9% that of the U.S. Over the past 100 years, Korea has undergone 17 periods of droughts and seven occasions of two-year consecutive droughts; since the 1990s, 62 cities and counties have experienced water shortages.
3. Flood damage
According to data collected over the past decade (1999-2008), torrential downpours of at least 100mm a day have been occurring 1.4 times more frequently than in the 1970s and 1980s. Heavy rainfall brings with it increased flooding and flood damage, caused in part by the poor conditions of levees, reduced capacities of existing dams, loss of wetlands, and the shifting of soil and sand over time.
Expenses caused by flood (2002-2006)
- Damage: KRW 2.7 trillion (equivalent of USD 2.2 billion)
- Restoration: KRW 4.2 trillion (equivalent of USD 3.4 billion)
4. Water pollution and eco-system damage
During the period of water shortage (every October to the following April) water quality plunges since there is less water to dilute pollutants, making the water unsuitable for drinking without undergoing special treatment. During this time, many rivers in the nation dry up, since there isn’t enough water for a steady flow.
Traditional efforts to raise the height of levees to guard against floods have caused excessive accumulation of soil deposits inside waterways, leading to exposed riverbeds during the dry season. The use of the riverbanks as farmland in combination with pesticides and fertilizers has also been a contributing factor in the deterioration of the riverside ecosystem.
