Government Secures 1 Billion Tons of Hidden Flood-Control Capacity This Summer, Cuts Damage With AI Forecasts

The government secured an additional 1.04 billion metric tons of flood-control capacity this summer by using agricultural reservoirs, power-generation dams, estuary dikes and other facilities. It also strengthened its forecasting and response systems by upgrading AI-based flood forecasts and introducing urban flood forecasts for the first time in major flood-prone areas of Seoul.

On November 3, the Ministry of Climate, Energy and Environment announced the results of its “2026 Summer Flood Response.” Nationwide precipitation this summer totaled 558.6 mm, just 76.1% of the average for a typical year (727.3 mm), but some areas were hit by record-breaking downpours. From August 15 to 18, Geoje City in South Gyeongsang Province received 968.1 mm of rain over four days, while the maximum hourly rainfall reached 124.5 mm, breaking the previous record of 104 mm. In late August, parts of Chungcheong and Jeolla also experienced extreme rainfall exceeding 100 mm per hour.

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In cooperation with relevant agencies, including the Ministry of Agriculture, Food and Rural Affairs, the ministry used existing facilities such as agricultural reservoirs, power-generation dams and estuary dikes as “hidden water reservoirs.” These facilities provided a total of 1.04 billion metric tons of additional flood-control capacity, equivalent to about three Hantan River Dams. Compared with the roughly 4 trillion won needed to build new dams, using existing facilities helped boost flood-response capacity while saving time and money.

Existing multipurpose dams and other facilities also released water in advance according to rainfall conditions. As a result, the number of dam sluice-gate releases fell to 23 this year from 69 last year. Releases from multipurpose dams dropped to 3 from 22, those from water-supply dams to 0 from 4, and those from power-generation dams to 20 from 43.

The AI-based flood forecasting system was also upgraded. Water levels at 223 flood-warning locations nationwide were automatically forecast at 10-minute intervals, and a double-check system was used in which flood forecasters verified the forecasts by comparing them with actual water-level changes and the results of physical-model analyses. This year, 38 flood alerts were issued in total: 31 advisories and 7 warnings. The ministry also sent 1,532 flood information notices and 233 notices related to flood-vulnerable areas to relevant agencies.

Urban flood forecasts were piloted for the first time in six Seoul districts: Yeongdeungpo, Dongjak, Guro, Gwanak, Seocho and Gangnam. The system predicts the extent and depth of flooding and issues flood advisories and warnings. On July 9, after water levels rose near Sindaebang, Sillim and Boramae stations along Dorimcheon Stream, the first flood advisory since the system was introduced was issued, and safety alert text messages were sent to residents. The ministry will assess the results of this year’s pilot program, draw up a comprehensive plan to expand the system nationwide by the end of the year, and plans to extend it to six major cities by the first half of 2030.

Inspections of flood-vulnerable facilities were also strengthened. The number of flood-vulnerable areas increased to 893 this year from 799 last year, and a total of 1,790 inspections were conducted. A further 5,248 river facilities, including embankments, and 63 dams were inspected. About 4.23 million storm drains nationwide were cleared a cumulative 8.98 million times, and a total of 17,688 km of stormwater pipes were dredged.

The authorities also coordinated with relevant agencies to respond to the unauthorized release of water from the Hwanggang Dam in North Korea and to extreme rainfall in Geoje City. When the Hwanggang Dam released water from July 20 to 30, the water level at Pilseung Bridge in Yeoncheon County rose to a peak of 10.28 meters. Authorities detected signs of the release using satellite imagery and alerted people to the danger through safety text messages and warning broadcasts. During the heavy rainfall in Geoje in August, they also monitored river levels and dam operations and provided local governments with information on potential dangers to support on-the-ground responses.

The ministry plans to strengthen links among water-resource facilities, including dams, reservoirs and estuary dikes, in preparation for the possibility that climate change will intensify compound disasters in which floods and droughts occur simultaneously.

This content was produced with the assistance of AI translation services.