Yongsan-gu Installs IoT Flood Warning System in Semi-Basement Alleyways

Sirens and Voice Alerts Trigger Automatically When Water Level Thresholds Are Reached
Securing the Golden Time for Resident Evacuation

Yongsan-gu in Seoul (District Chief Kim Kyungdae) has become the first in the country to install an Internet of Things (IoT) radar-type flood warning system in alleyways densely populated with semi-basement homes, taking proactive measures against natural disasters such as heavy rain and flooding.

IoT radar-based flood warning system installed in a densely populated semi-basement area of Yongsan District. Provided by Yongsan District.

On September 20, the district office announced that the system had been installed at six locations in low-lying areas where concern over casualties from floods is particularly high due to the concentration of semi-basement residences. The pilot operation was completed by August, in accordance with the summer natural disaster response period from May 15 to October 15.

Prior to installing the system, field surveys were conducted to assess the density of semi-basement homes in low-lying areas, past flood histories, and conditions for installation. Through this process, the district identified risk factors for each alley and selected appropriate equipment and operational methods tailored to the characteristics of each location.

Previously, during heavy rainfall, district officials had to patrol the sites or rely on resident reports to identify flooding. When sudden downpours occurred, it took time to verify the situation and respond on-site, making it difficult to secure the critical time needed for residents to evacuate safely.

The IoT radar system measures road water levels in alleyways every minute and transmits the data to a central server. Officials can monitor changes in water level and assess flood risk in real time without physically visiting the site. A key feature of this system is that water level monitoring, which was previously focused on rivers and major roads, has been expanded to residential alleyways where people live.

When water levels reach designated thresholds, on-site sirens and voice alerts are automatically activated. Alert levels are set at 5 cm for caution, 10 cm for warning, and 15 cm for critical status, providing guidance about risk situations and methods of evacuation. Text alerts are also sent to designated support partners and care officials to facilitate on-site checks and assist with resident evacuation.

Yongsan-gu has shifted from a reactionary system focused on post-event monitoring to a proactive framework centered on detection, communication, and evacuation, thereby enhancing its ability to promptly warn residents and prevent casualties during heavy rainfall. The district plans to further develop the system by analyzing water level data to refine alert standards and expand both coverage and functions, particularly in flood-prone areas.

District Chief Kim Kyungdae stated, "What matters most is not responding after flooding occurs, but detecting risks in advance and promptly notifying residents," adding, "We will continue to advance our IoT-based real-time monitoring system to ensure the safety of flood-prone areas, and dedicate our efforts to protecting the lives and property of our residents."

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