The Seoul Metropolitan Government (SMG) will implement new flood safety measures starting this May to prevent unfortunate casualties like the semi-basement housing accident in Sillim-dong last summer. The city announced that it will start a flood forecast/warning system for the first time in the country so that citizens can be aware of flooding in advance. The city will also run an evacuation assistance service for neighbors to help the disaster vulnerable living in semi-basement houses to quickly evacuate when a forecast or warning is issued.

The goal is to prevent life-threatening accidents in advance by preparing for a crisis on their own through flood prediction, and to secure a golden time for evacuation by promptly sending a helping hand to the disaster vulnerable who are unable to respond by themselves.

This project is one of the city’s strategies to promote a comprehensive flood safety net as part of its flood prevention measures for the next decade to respond to the climate crisis, which has become a reality.

The evacuation assistance service is run by a cooperative community of residents, who are dispatched to the site from the flood forecast stage to prevent human damage to the disaster vulnerable living in semi-basement houses. It is planned to consist of a total of around 5 people: community leaders who are well versed in the local situation, neighbors living in the same building as the target household or living in an adjacent street within 5 minutes on foot, and public officials in charge of care services.

When flood forecasts and warnings are issued, caring officials promptly disseminate the issuance status and weather information to assistance residents and the disaster vulnerable via emergency contact systems, such as KakaoTalk. Then the assistance personnel is contacted and immediately dispatched to the households of the vulnerable to check whether there is an abnormality in the water barrier, and evacuate them to a safe place if signs of flooding are found. The service is provided to hopeful households out of a total of 1,071 households of the severely disabled, seniors, and children living in semi-basement houses, where more than two-thirds are underground.

The flood forecast/warning system warns district offices and related organizations, including police, firefighting and road authorities, assistance personnel, and citizens of the flooding in advance, when rainfall and water depths above a certain standard are measured by rain gauges and road level gauges installed throughout Seoul.

Seoul issues a flood forecast for each district if any of the following conditions are met: rainfall per hour exceeds 55 mm; rainfall per 15 minutes exceeds 20 mm; and flood depth exceeds 15 cm based on road water level. The plan is to disseminate the message to district offices and related organizations, including police and firefighting authorities, and major facilities management organizations, including the road authority, via group chat rooms and text messages.

Districts for which a flood forecast has been issued then issue a flood warning after determining whether there is danger through CCTV checks in flood-concerned areas and dispatch to the site. It notifies all citizens in the area of emergency via a cell broadcasting service (CBS) and warning broadcast.

The city expects that when the flood forecast/warning system is implemented, district offices, police stations, fire stations, and citizens will be able to recognize flooding in advance, allowing them to respond appropriately to each situation.

In addition, the city introduced guidelines for citizens to act when a flood warning is issued. For example, citizens in underground parking lots should leave their vehicles and escape immediately when the water fills up; residents of semi-basement houses, merchants in underground shopping malls, and building managers should install flood prevention facilities, such as sandbags and water barriers. Drivers should not enter a road or underpass filled with water, and if they enter a flooded underpass, they should leave the vehicle and evacuate quickly.

Seoul announced that it would take more detailed safety measures against flood damage to prevent any further fatal accidents due to flooding caused by abnormal heavy rain.