Heavy rains and subsequent flooding in the Ahlat district of Bitlis, eastern Türkiye, have turned the waters of Lake Van brown as floodwaters from nearby streambeds poured into the lake.
Following meteorological warnings, rain mixed with snow fell in the district, leading to runoff that carried sediment into the lake. The muddy waters, particularly noticeable along a 7-kilometer (4.35-mile) stretch of the Ahlat-Tatvan road, created a striking contrast against the lake’s usual blue hue. The scene, captured from the air, drew attention from both locals and travelers.
Many drivers and residents stopped along the Ahlat-Tatvan highway to observe and document the unusual color shift. Yunus Nazlı, one of the onlookers, described witnessing the phenomenon for the first time. "Lake Van has turned a reddish color with the rainwater. We've never seen anything like this before. We had to stop and take a video," he said.
As Lake Van’s water levels drop due to seasonal changes, drought and evaporation, an ancient geological wonder has become more visible along the shoreline. Microbialites, known as "underwater fairy chimneys," have surfaced, drawing interest from scientists, nature enthusiasts and photographers.
These formations, which have taken thousands of years to develop, can now be seen in several areas along the lake’s coast. Visitors exploring the Altınsaç and Göründü neighborhoods of Van’s Gevaş district have even taken to canoes to get a closer look at the newly exposed microbialites.
Associate professor Ataman Altuğ Atıcı from Van Yüzüncü Yıl University’s Faculty of Fisheries highlighted the significance of these formations. He explained that microbialites form through interactions between cyanobacteria, microalgae and chemical sediments, leading to calcium carbonate precipitation. Some of these formations, resembling towers, can reach up to 40 meters (131 feet) in height.
The discovery of these massive microbialites dates back to 1974 when researchers noticed unusual acoustic readings during a survey of Lake Van’s Adilcevaz region. Subsequent studies in 1989 confirmed the presence of lime-rich cyanobacterial sediments, particularly in Tatvan Bay and the southern part of Adilcevaz.
Atıcı emphasized the potential of microbialites for nature tourism. "Microbialites are delicate structures, but with proper promotion, they could attract visitors for diving tourism and guided tours," he said. However, he cautioned that these formations are fragile and should be protected from damage.
With some microbialites already exceeding 40 meters (131.23 feet) in height, researchers predict they could grow to 50-60 meters in the coming years. Their presence in various locations, including Erciş, Edremit and Gevaş in Van, as well as Adilcevaz in Bitlis, presents an opportunity for integrating these natural wonders into tourism efforts.
While recent droughts and excessive evaporation pose challenges for Lake Van, the emergence of these unique geological formations underscores the need for conservation and sustainable tourism planning.
