The Institute for Water ‘Josip Juraj Strossmayer’, in partnership with SeaCras, has developed a new system that combines satellite observations with field measurements to support more comprehensive, next-gen water body monitoring. More precisely, the monitoring of inland, coastal waters as well as the open sea.
The approach makes it possible to monitor a large number of water bodies at the same time, from large and small rivers to lakes, water reservoirs, fish ponds and accumulation lakes, coastal areas and seas. By connecting remote sensing data with traditional field monitoring, the system can evaluate biochemical and physical parameters defined by Water Framework Directive (WFD) and Marine Strategy Framework Directives (MSFD). Also, the system helps to detect rapid changes of water quality earlier and provide a clearer picture of how aquatic ecosystems respond to environmental pressures and protection measures. Especially important aspect is cross-border monitoring to assess what migrates to Croatian waters from upstream in the Danube river system, as well as from territorial waters of neighbouring countries at the Adriatic sea.
Just under a year ago, we signed a cooperation agreement with the Josip Juraj Strossmayer Water Institute. Today, partners are introducing a new generation of satellite-based monitoring for the condition of dynamic and stationary water bodies by cutting-edge technology, which puts Croatia in the top performing countries.
By monitoring the quality of riverine systems and streams in Croatia, SeaCras is able to record human impacts within the national territory, as well as transboundary influences that may affect water conditions upstream and downstream. This allows for the first time to evaluate the effect of the river system on its endpoints – seas and lakes.
Similar technologies are already being applied in several European countries, including Germany, Finland and Sweden. Through this cooperation, we have launched an advanced water monitoring technology we can be proud of — a best-in-class solution developed through domestic expertise and production.
From the Drava River to Broader Water Monitoring
The first demonstration was carried out on the Drava River, following the launch of one of Croatia’s largest wastewater treatment plants. According to the Water Institute, the comparison of conditions before and after the facility began operating showed early signs of improvement in water quality, while satellite observations confirmed the findings gathered through field monitoring.
The analysis recorded changes in several indicators used to assess ecological pressure and eutrophication in river ecosystems, which refers to excessive nutrient enrichment, mainly from nitrogen and phosphorus compounds, which in turn causes algal blooms. These parameters are important for understanding how nutrients and other pressures affect aquatic environments, particularly in relation to algal growth and overall ecosystem balance.
High spatial resolution also enables the system to go beyond major rivers and lakes. It opens the possibility of monitoring smaller waterways as well, supporting more detailed assessments at local, national and cross-border levels.
Satellite view of the distribution of chlorophyll-a concentrations in the Drava River near Belišće, produced in collaboration between the Josip Juraj Strossmayer Water Institute and SeaCras.
Better Data for More Confident Decisions
For water management, this marks an important shift. Investments in environmental protection can be assessed not only through the infrastructure built, but also through measurable changes in the environment itself. By combining satellite data and field measurements, decision-makers can better understand what is happening in the water after interventions are made.
The same approach has strong potential for wider use across the Adriatic and other coastal areas, which has already proven to be successful in coastal areas such as Zavrtnica and Jablanac. It can support the monitoring of coastal urbanisation, wastewater treatment impacts, river inflows, climate-related pressures and individual events that leave visible traces in water or the sea.
For SeaCras, the collaboration reflects the growing role of satellite-based intelligence in protecting water ecosystems. By turning complex environmental data into practical information, the system can support earlier detection, stronger evidence and more informed decisions for the sustainable management of rivers, lakes, coastal areas and seas.
Get in touch with our SeaCras team to explore how satellite-based intelligence can support more informed, data-driven water management.