Although torrential rain fell during the July monsoon, rainfall varied widely by region, turning dam storage rates to a "red light" in Yeongnam and Honam and a "blue light" in the Chungcheong region. Experts noted, "As climate change strengthens the locality of rainfall, nationwide water management is becoming more difficult."
◇ Five of eight drought-response dams in Yeongnam and Honam below 40% storage
The storage rate is an index that shows, as a percentage (%), the proportion of water currently stored out of the maximum total volume a dam can hold. Among the eight major drought-response dams in Yeongnam and Honam, the storage rate at five has already fallen below 40%.
Recent storage rates were tallied as follows: ▲ Seomjin River Dam 24.7% (67.9% a year earlier) ▲ Unmun Dam 27.1% (63.6% a year earlier) ▲ Seongdeok Dam 30.8% (69.7% a year earlier) ▲ Yeongcheon Dam 33.3% (73.1% a year earlier) ▲ Miryang Dam 33.7% (74.8% a year earlier) ▲ Andong 40.3% (49% a year earlier) ▲ Imha Dam 42.9% (62.1% a year earlier) ▲ Pyeongnim Dam 55.4% (81.4% a year earlier).
When the storage rate falls to 50% of the average year or lower, it reaches the drought "alert" stage. If it drops further to 40% or lower, it enters the highest "severe" stage. In such conditions, authorities review or implement emergency water supply and rationing.
Unmun Dam has now entered the "severe" stage. Seomjin River and Pyeongnim dams are at the "attention" stage, while Miryang, Yeongcheon, Andong, Imha, and Seongdeok dams have moved to the "caution" stage. In effect, a "red light" is on at all eight major drought-response dams in Yeongnam and Honam.
With the situation unfolding this way, Yoon Seok-dae, president of Korea Water Resources Corporation (K-water), visited Miryang Dam on the 29th. Earlier, Yoon said there was "no need to worry about a shortage of industrial water for the Honam semiconductor cluster." In addition, Minister Kim Seong-hwan of the climate ministry held an "emergency countermeasures meeting on drought response in the southern region" on the 31st.
By contrast, dams in the Chungcheong region, where rain was concentrated, have ample storage. ▲ Chungju Dam 69.1% (59.5% a year earlier) ▲ Daecheong Dam 61.6% (63.5% a year earlier).
◇ Rainfall polarization stands out… "Water management getting harder, phased investment needed"
The gap in dam storage rates between Yeongnam–Honam and Chungcheong stems from regional rainfall differences. During this monsoon (July 8–10, July 17–23), the Chungcheong region saw torrential rain. Rainfall was tallied as follows: ▲ Cheonan, South Chungcheong 267.1 mm ▲ Gyeryong, South Chungcheong 259 mm ▲ Sejong 244.5 mm ▲ Buyeo, South Chungcheong 243 mm.
During the same periods, rainfall in Yeongnam and Honam was much lower. ▲ Cheongsong, North Gyeongsang 19.5 mm ▲ Jangseong, South Jeolla 20.5 mm ▲ Miryang, South Gyeongsang 43.3 mm ▲ Yeongcheon, North Gyeongsang 69.7 mm ▲ Cheongdo, North Gyeongsang 89 mm ▲ Imsil, North Jeolla 144.6 mm, generally staying under 100 mm.
Regarding this, an official at the water resources corporation said, "The polarization of rainfall by region has become clear," adding, "Uncertainty in water operations by dam basin is also increasing."
Ahn Jong-ho, a senior research fellow at the Environmental Research Institute, said, "Going forward, rather than cycles of drought, regional concentration and intensity differences may grow," adding, "Phased investment is needed in diversifying water sources and managing demand."