Pilots

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  Lake Bled (SI)

  Although Lake Bled is a very small Alpine lake (1,5 km2) it is a national icon and the most important Slovenian lake for tourism. Celebrated for its stunning island, Lake Bled has seen rising environmental pressures from tourism and shoreline development.    

  
  

  
  Lake Bled. (Photo: Anja Bubik)
  Activities like tourism, old infrastructure and fish feeding, add to nutrient pollution, fueling potentially harmful cyanobacterial bloom. These blooms can disrupt the lake’s delicate ecosystem, turning the seemingly pristine lake water putrid brown or red. Lake Bled is the only lake in Slovenia which occasionally turns into scarlet color, all other Slovenian lakes and accumulations with cyanobacterial bloom are more greenish in color (www.ciano.si).  

  
  

   
  A dense scarlet bloom  of the potentially toxic cyanobacteria Planktothrix rubescens on the lake surface. (Photo: Tina Eleršek)
  To tackle these challenges, the DiMark project will study different Alpine lakes and create advanced visualization tool and model for early warning system. While being the smallest key lake in DiMark, Lake Bled is on the limit for satellite observation, but anyway, by integrating traditional techniques with satellite observations, DiMark will try to predict and mitigate the impacts of eutrophication on Lake Bled and to protect its ecological well-being for future generations. 

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  Lake Mondsee (AT)

  Mondsee is a mid-sized Alpine lake in Austria (around 14 km²), located in the Salzkammergut Lakes area, known for its warm summer temperatures and popularity among locals and tourists. It’s surrounded by villages and settlements and agriculturally used landscape. This lake allows plenty of recreational activities like swimming, diving, sailing, and paddleboarding (SUP) as well as camping or fishing. Its shoreline is home to cultural events and festivals throughout the year, making it one of the more active lakes in the Salzkammergut region. The lake supports a variety of aquatic species, including two native fish species leading to its Natura 2000 status. The lake ecosystem provides habitat for red-list waterbirds, amphibians and mammals. Its wetlands and littoral zones are ecologically most valuable, though increasingly pressured by human activity. The relatively large catchment of 250 km² results in a higher sensitivity of the lake ecosystem to global change, including eutrophication through run-off events but also by tourism and in general land use. These nutrients can feed algal and cyanobacterial blooms, especially after extreme precipitation events and stratified conditions in the water column. Such blooms may reduce water quality, endanger aquatic life, and can disrupt recreational use - posing risks both to the environment and public health
  This is why DiMark offers an excellent opportunity for this particular lake to co-develop, together with local stakeholders and other experts, both a visualisation tool and a cyano-risk prevention model, enabling better and more efficient water management.

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  Lake Garda (IT)

  Lake Garda, the largest lake in Italy (covering over 370 km²), is one of the most iconic and visited lakes in the Alpine region. With its mild climate and easy access from cities like Milan and Verona, Garda attracts millions of visitors every year for swimming, sailing, windsurfing, and sightseeing.
  Despite its beauty, Lake Garda faces increasing pressure from tourism, especially during peak summer months, leading to overloaded wastewater systems and increasing pressure on the lake’s natural habitats, high recreational use - from boats and marinas to lakeside resorts - contributes to nutrient inflows, which over time can lead to eutrophication and the appearance of harmful algal blooms.
  As part of the DiMark project, Lake Garda will serve as an important pilot for testing scalable monitoring systems and the model for cyano-risk.
  The goal is to give local authorities and lake managers a clearer picture of when and where water quality issues may arise - helping them respond more effectively and plan long-term measures to protect the lake's ecosystem. For a lake that provides drinking water, supports agriculture, fisheries, and tourism, such a tool is essential for improved water management and protecting environmental health.

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  Upper Lake Constance (D/CH)

  Upper Lake Constance - known as Bodensee - Obersee - is one of the largest lakes in Central Europe, lying between Germany, Austria, and Switzerland. Covering more than 470 km² and reaching depths of over 250 m, it plays an important role in drinking water supply, fisheries, recreation, and cross-border cooperation. With alpine rivers like the Rhine flowing into it, and an extensive catchment that includes agricultural, industrial, and urban areas, Lake Constance is an important and complex freshwater system.
  Although Lake Constance has benefited from decades of international cooperation on water protection, new problems are emerging. Warmer summers and changing rainfall patterns can promote algal and cyanobacterial blooms, especially in shallow bays and areas near river inflows. These blooms may reduce water quality, threaten biodiversity, and pose a risk to bathing areas. Likewise invasive species such as the Quagga mussel disrupt the food web and energy flows of the lake. The large size of the lake and the fact that it is shared by three countries make coordinated monitoring and rapid response particularly important.
  As a key pilot site within the DiMark project, Upper Lake Constance offers a unique opportunity to test cross-border approaches to early-warning systems and data visualisation tools. DiMark will link traditional water quality monitoring with satellite-based Earth observation, helping authorities detect and track bloom risks in near real time. This is especially valuable in border zones, where lake conditions can change quickly and responsibilities are shared.

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  Lake Geneva (CH/FR)

  Lake Geneva - or Lac Léman, as it’s known in French - is one of Europe’s largest lakes, stretching across Switzerland and France with a surface area of over 580 km². Surrounded by vineyards, the nearby Alps, and cities like Geneva, Lausanne, and Évian, the lake is both a natural wonder and an active, multi-use lake supporting transport, tourism, and water supply. It provides drinking water, supports fisheries, fuels hydropower, and draws millions of people to its shores each year for swimming, sailing, and tourism.
  In the past, Lake Geneva suffered from severe eutrophication, especially during the 1970s and 1980s. Intensive agriculture, industrial waste, and untreated sewage led to nutrient overload, algal blooms, and oxygen depletion in deep water. A long-term international effort involving both countries helped reduce phosphorus levels and improve wastewater treatment, setting a good example for cross-border water protection.
  Today, the picture is changing again. Rising surface temperatures and longer stratification periods can make the lake more vulnerable to algal and cyanobacterial blooms, even at relatively low nutrient levels. Warmer summers and intense rainstorms increase the risk of runoff and re-suspension of nutrients from sediments -  especially near the Rhône inflow and urban shorelines.
  For DiMark, Lake Geneva offers a chance to apply modern tools to an old but evolving challenge. The lake is large, deep, and internationally governed - making it an ideal testing ground for the satellite-based visualisation platform and the cyano-risk model. These tools will help lake managers, public health authorities, and municipalities respond more quickly to signs of bloom development and shifts in water quality.

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  Greifensee (CH)

  Greifensee is a small but ecologically significant lake located just northeast of Zurich, Switzerland, covering about 8.5 km². Despite its modest size, it plays an important role in the region: serving as a drinking water source, recreation area, and biodiversity hotspot. Its proximity to urban centers makes it a popoular destination for walking, birdwatching, kayaking and swimming.
  Greifensee is experiencing elevated nutrient levels from agriculture and wastewater, which cause oxygen depletion and cyanobacterial blooms. Thanks to improvements such as improved sewage treatment and stricter agricultural practices, phosphorus inputs have decreased, but they remain noticeable and nutrient recycling from sediments prevents the lake’s recovery from eutrophication, too.  Its manageable size makes detailed monitoring possible, but internal nutrient cycling, variable bloom conditions, and diverse human uses continue to present challenges. Warmer water temperatures and stronger thermal stratification can extend the bloom season and reduce oxygenation in deeper layers, which may occasionally release phosphorus stored in sediments, supporting new blooms even if external nutrient inputs have been reduced.
  Within the DiMark project, Greifensee is a key pilot site for understanding how small, shallow lakes at lower elevations - especially those at the interface of agglomerations and rural areas - may respond to warming and changing nutrient dynamics. This will help local authorities anticipate harmful conditions and deal with water management more efficiently.