Environment ministry to issue annual hydrological report covering 2,560 sites

The environment ministry said it would release the 2025 Korean Hydrological Survey Annual Report, documenting a wider monitoring network for rivers nationwide alongside expanded AI flood forecasting.

To support expanded AI flood forecasting, the ministry said it has been extending water-level monitoring to smaller streams and increasing automated flow monitoring. The report contains measurements collected during 2025 at 2,560 sites across six categories: rainfall, water levels, river flows, sediment transport, evapotranspiration and soil moisture.

Water-level data covered 1,217 locations, 186 more than a year earlier, while flow measurements came from 634 sites, up 18 from a year earlier. Automated flow-monitoring sites rose to 170 from 71. The ministry's four flood control offices accounted for 180 of the new water-level locations, while Korea Water Resources Corp. added one and Korea Hydro & Nuclear Power added five.

“We will continue to provide reliable hydrological data for scientific flood forecasting and water management,” Kim Gu-beom, head of the Han River Flood Control Office, said.

The data underwent quality control under relevant standards and certification procedures, the ministry said. The full PDF will be available on the Han River Flood Control Office website from Aug. 20.