Fixed hyperspectral towers to be added at three Nakdong River sites

Satellite-based wide-area surveillance to operate in tandem with tower network

The National Institute of Environmental Research, an agency under the Ministry of Climate, Environment and Energy, announced Wednesday it will upgrade its real-time, wide-area algae monitoring system by integrating hyperspectral sensors and satellite remote sensing with AI-based analysis technology.

The upgrade will proceed along two tracks: real-time algae observation using fixed hyperspectral towers, and the construction of a satellite-based wide-area algae surveillance system.

Fixed hyperspectral towers capture far more wavelength data than conventional cameras through their onboard hyperspectral sensors, enabling real-time analysis of algae-related pigments such as chlorophyll-a and phycocyanin that are difficult to distinguish with the naked eye.

Towers are currently installed and operating at the Chilseo site on the Nakdong River and at Daecheong Lake on the Geum River. Starting this month, three additional units will be installed at Haepyeong, Gangjeonggoryeong and Mulgeum-maeri on the Nakdong River, expanding the network to five towers in total.

Data collected by the hyperspectral sensors will be integrated with water quality sensors, meteorological instruments and closed-circuit television, then analyzed using an AI-based deep learning model.

The system currently measures chlorophyll-a and phycocyanin concentrations in real time. Authorities plan to develop technology that will use AI to automatically analyze harmful cyanobacteria cell counts — measured in cells per milliliter — a key indicator under the algae alert system.

Algae monitoring system mounted on a hyperspectral tower [National Institute of Environmental Research]
Algae monitoring system mounted on a hyperspectral tower [National Institute of Environmental Research]

The institute is also using imagery from the Sentinel-2 satellite operated by the European Space Agency to quantitatively map the distribution of chlorophyll-a and phycocyanin concentrations through atmospheric correction and AI-based image analysis.

Algae concentration distribution maps covering the Nakdong, Geum and Yeongsan river systems are currently being produced and made publicly available through the Water Environment Information System.

The upgraded monitoring framework will combine precise point-level observation with wide-area watershed surveillance. The combination is expected to deliver scientific data more quickly to local governments and relevant agencies for advance response — supporting more effective operation of the algae alert system, preparedness at water intake and treatment facilities, and the seasonal algae management program.

"The convergence of AI and advanced remote sensing technology is a core technology that will fundamentally transform water quality management in the era of climate change," said Kim Kyeong-hyeon, head of the water environment research division at the National Institute of Environmental Research. "We will continue to upgrade our intelligent, real-time and predictive algae response system to create a water environment where the public can feel safe."


thlee@heraldcorp.com