The Ministry of Environment (Minister Kim Wansup) announced that this summer, the “Smart Flood Alert System,” expansion of dam flood control, and river maintenance have played a significant role in protecting the lives of citizens from floods.

The “Smart Flood Alert System” refers to the use of smart digital technologies, such as artificial intelligence (AI) flood forecasting, navigation guidance, and text ale.rts for areas at risk of flooding, introduced by the Ministry this year to enhance flood response and provide citizens with quick and accurate information about flood risks.

【Analysis of Precipitation During this Summer】 

During this year’s monsoon season (June 19 to July 27), there was a significant increase* of 32.5% in rainfall compared to the average (1991-2020). In particular, the heavy rain fell concentrated in a short period over a narrow area, making flood response challenging.

* The national rainfall during the monsoon season was 475 mm, representing a 32.5% increase compared to the average of 357 mm.

In just the month of July, Paju in Gyeonggi-do saw over 800 mm of rain, while Iksan in Jeollabuk-do and Seocheon-gun in Chungcheongnam-do experienced over 700 mm, resulting in a phenomenon where more than half of the annual average precipitation (approximately 1,300 mm) was concentrated.

On July 10, records for the highest hourly rainfall were broken, with 146 mm per hour in Gunsan, Jeollabuk-do, and 142 mm per hour in Iksan, Jeollabuk-do, experiencing heavy rain that exceeded a 500-year frequency. 

In addition, due to concentrated heavy rainfall in the metropolitan area from July 17 to 18, Paju in Gyeonggi-do received 620 mm of rain over two days, with the maximum hourly rainfall recorded at 101 mm, exceeding a 500-year frequency.

Meanwhile, from September 20 to 22, heavy rain fell nationwide due to the weakened tropical depression that had transformed from Typhoon No. 14 (Pulasan), with Changwon in Gyeongsangnam-do receiving 531 mm of rain over two days, marking a 500-year frequency level.

【Securing Evacuation Time for Floods Using Artificial Intelligence Technology】 

To effectively respond to the heavy rains that occur every year, the Ministry conducted flood forecasting using artificial intelligence technology for the first time this year. The system automatically predicts river water levels every 10 minutes and provides risk* ale.rts, and after verification by flood forecasters, flood warnings (flood advisories and ale.rts) are issued**.

* In cases where the river water level is expected to rise sharply or to reach or exceed flood warning threshold levels 

** Flood advisories will be issued when the expected river flow exceeds 50% of the planned flood volume, and flood ale.rts will be issued when it exceeds 70%

By utilizing artificial intelligence technology, the time required to issue flood warnings was significantly reduced, and flood warnings could be quickly issued for approximately three times the number of points compared to the previous year*.

* Flood warning points: 75 in 2023 (63 national, 12 local) → 223 in 2024 (93 national, 130 local)

Through the significant expansion of flood warning points, a total of 170 warnings were issued this year, which is approximately five times higher than the recent 10-year average of 34. In particular, out of the 170 warnings, 133 (78% of the total) were issued at newly expanded warning points. In addition, flood warnings for local rivers were issued, increasing the number of new warning points by about 11 times compared to before, ensuring ample evacuation time to prepare for flooding in vulnerable local rivers.

In addition to flood warnings predicting river water levels before flooding occurs, a total of 2,495 pieces of flood information were disseminated to relevant agencies, based on monitoring river water levels every minute from the 673 installed water level observation stations across the country.

In addition to the existing methods of disseminating flood warnings and information via fax and SMS, a total of 8,651 notifications were transmitted this year through voice messages (VMS*) to local government officials and responsible personnel, and direct phone notifications were also made to local government officials. 

* Voice Message System: Automatically converts text into voice for transmission, ends the call after con.firmation of receipt.

This year, due to heavy rains, dangerous situations occurred in some areas where river water levels exceeded the planned flood levels* on July 10 in the Chungcheong region (Yudungcheon in Geumsan-gun, Seohwa-cheon in Okcheon-gun), on July 18 in the metropolitan area (Osancheon in Osan, Bokhacheon in Icheon), and on September 21 in the Gyeongnam region (Joman River in Gimhae). However, by immediately disseminating flood warning information to local governments in advance, residents were able to evacuate, preventing loss of life.

* The maximum water level defined during river design, which indicates the highest level at which water can flow in the river

Along with predicting river water levels, urban flooding forecasts were also carried out without any disruptions. Following last year’s warnings for Seoul (Dorimcheon), this year the forecasts were expanded to include Gwangju (Hwangryonggang), Pohang (Naengcheon), and Changwon (Changwoncheon) areas. A total of 56 notifications were sent to local governments regarding areas expected to experience flooding by checking the water levels of rivers and sewer systems, allowing residents in low-lying areas to evacuate.

【Providing Flood Information that is Easy for the Public to Understand】 

The communication system was improved to convey flood warning issuance and other dangerous situations in a way that the public can easily understand, enabling them to prepare for flood risks.

Starting from July 2024, vehicle drivers receive audio guidance through navigation systems when entering near flood al.ert issuance points or dam discharge points for the first time. A total of 41 flood al.ert issuance notifications and 64 dam discharge notifications were provided via the navigation system to encourage caution while driving in hazardous areas such as underpasses or low-lying regions. 

 

In addition, the safety notification messages (CBS) sent to residents in areas with 170 flood warnings were improved. Previously, information was provided mainly in text form, but starting in May this year, the messages utilize individual mobile phone location data (GPS) to inform recipients whether they are in a flood-prone area and to provide a map of nearby flood-prone areas, allowing them to quickly evacuate from dangerous locations.

【Flood Control by Multi-purpose Dams】 

Meanwhile, the Ministry actively implemented flood control through 20 multi-purpose dams across the country.

In order to hold as much water as possible during heavy rains, flood control capacity was secured at approximately three times the design level (6.25 billion m³) through concentrated discharges from multi-purpose dams before the flood season (June 21 to September 20). During heavy rains, efforts were made to retain maximum water in the dam to minimize the rise of water levels in downstream rivers.

During the heavy rains from July 9 to 10, seven out of the 20 multi-purpose dams retained all incoming water, while the remaining 13 dams retained an average of 83% of their inflow to ensure the safety of downstream rivers. In particular, at Yongdam Dam, which fully retained its inflow during the severe flood situation in the Chungcheong region on July 10, and Daechung Dam released only 10% (688 m³/s) of its inflow (6,866 m³/s), minimizing the rise in water levels of the Geum River downstream.

During the heavy rains from September 20 to 22, 17 out of the 20 multi-purpose dams retained all incoming water, while the remaining three dams retained an average of 72% of their inflow, actively working to reduce flooding in downstream rivers.

【Expansion of River Maintenance】 

In addition, the Ministry is actively promoting river maintenance, including reinforcing embankments and dredging rivers, to create flood-safe rivers. The national river maintenance budget, which was around KRW 450 billion last year, has been significantly increased to approximately KRW 660 billion this year, representing an increase of about 47%. These efforts aim to strengthen the flood response capability of rivers through proactive maintenance before the flood season.

In addition, the government is strengthening its responsibility for tributaries and small rivers. Twenty local rivers vulnerable to flooding* will be upgraded to national rivers, allowing the government to manage them directly and increase budget investment. Plans are in place to sequentially promote river maintenance, and with this upgrade, the number of national rivers is expected to increase from 73 locations and 3,602 km in 2023 to 89 locations and 4,069 km by 2025.

* By October 2024, the upgrade of 10 locations will be completed (eight newly designated places and two extended sections).In January 2025, an additional 10 locations are scheduled to be upgraded (eight newly designated places and two extended sections).

In addition, the government is directly maintaining sections of local rivers affected by the rising levels of national rivers. This year, 411 “national river drainage impact sections” have been designated for direct maintenance by the government, with maintenance prioritized for the 20 most urgent locations.

Meanwhile, through the installation of over 8,000 closed-circuit televisions (CCTVs) across all sections of national rivers (3,602 km) to eliminate blind spots, real-time monitoring of river conditions has been implemented starting this year. 

Local governments can also monitor these CCTVs to respond effectively, checking for residents walking along the riverside or camping vehicles during rain, allowing for prompt evacuation and access control.

【Future Plans】 

The Ministry plans to enhance the flood response system by improving the details based on the experience gained from the newly introduced ‘Smart Flood Alert System’ this year, as well as strengthening flood control through dams and river maintenance.

Particularly considering that flood warnings were primarily issued for local rivers this year, there is a need to expand water level observation stations for local rivers that are vulnerable to flooding. 

The Ministry plans to install water level observation stations in 258 local rivers by the end of this year and to provide real-time river water level and flood information starting next year. 

※ Water level observation stations: May 2024 - 673 total (310 national, 363 local) → December 2024 - 931 total (310 national, 621 local)

Kim Gu-beom, Director-General of Water Resources Policy Bureau, stated, “As strong and heavy rains are becoming more common compared to previous years, the role of the government in protecting the lives of citizens is becoming increasingly important.” He added, “We will operate the Smart Flood Alert System, which was introduced for the first time this year, without disruptions, and thoroughly manage dams and rivers to ensure that citizens are safe from flooding.” 

For further information, please contact the Public Relations Division. 

Contact person: Gina Lee, foreign media spokesperson

Phone: +82-44-201-6055

Email: gcjgina @gmail.com