Croatian beaches deter – Polish tourists complain

The editors of Water Matters have received, disturbing photos from a disappointed reader – the water off the coast of Istria resembles a brown, slimy slush. The strange phenomenon has already been reported in the world media, explaining that Croatian beaches have been in the zone of a phytoplankton bloom. Can vacationers feel safe? We would also like to remind you of the controversy over the pollution of the Hwar canal by cruise ships. So what is really going on in the waters of the Adriatic Sea?

Holiday drama in Istria

The Istrian peninsula, which is a popular tourist region in Croatia, in 2023. attracted 4.8 million tourists, accounting for nearly a quarter of all holiday visits to the country. Unfortunately, this year will be remembered by many families with disappointment and distaste. After all, a dream vacation on the Adriatic turned into anguish after the seawater turned brown and foamed. Croatia’s famous beaches have also lost their appeal, becoming covered in slippery dirt and strange clumps. Out of fear of entering the water, some tourists are considering cutting short their stay, according to Croatian portal 24sata.hr.

A strange, slippery and foamy residue appeared in the water suddenly, on the night of Thursday to Friday, and has persisted for several days. The same disturbing phenomenon is observed by tourists vacationing in Rovinj, Barbariga, Poreč and many other places – so you can’t even drive to the neighboring beach. Disappointed vacationers send photos to the media, publicizing their frustration.

The situation has already been addressed by relevant government agencies. The Ministry of Environmental Protection and Green Transformation assures that the quality of water at bathing beaches in Istria is excellent, which is confirmed by samples taken twice a month. However, more information on the cause of the pollution is provided by the Institute of Public Health, explaining the phenomenon by phytoplankton blooms, which may explain the presence of a slimy, foamy layer in the water.

Blooming sea

According to Ing. Dolores Griles of the Croatian Institute of Public Health, the frothy, slippery brown water and the sediment left behind on the beach is the result of a rare natural phenomenon called sea blooms. It was reportedly observed as early as the 18th century, but has intensified since the 1980s, and has recurred annually since 2000. The changing climate and damage to marine ecosystems caused by human activity may be to blame.

Croatian beaches are struggling to cope with the negative effects of the cumulative heat waves that have been haunting the Balkans since April, as well as elevated seawater temperatures. In addition, heavy spring precipitation has contributed to the fact that surface runoff has transported significant amounts of nutrients from agricultural areas to the sea. These substances are an excellent food for phytoplankton, which leads to their excessive growth, negatively affecting the state of marine ecosystems and the attractiveness of beaches.

Dr. Irena Ciglenečki-Jušić, who manages the Marine Physics and Aquatic Systems Chemistry Laboratory at the Bošković Institute (IRB), has been tracking blooms in the sea for years in cooperation with scientists from other research units. According to her, three years ago they first appeared in the central Adriatic, affecting Kaštela Bay and Šolta Island. Fortunately for tourists, however unappetizing the brown sea water looks, unlike our Baltic blue-green algae, it poses no health risk to bathers.

Croatian beaches not without problems

Phytoplankton blooms are not the only environmental challenge facing the Croatian coast. In early June, extensive oil stains were spotted in the sea near Premantura, in southern Istria, with an unpleasant odor reaching as far as the coastal campsite. Thanks to the immediate response of emergency services and the extensive mobilization of local authorities, an ecological disaster was averted. The source of the leak has not yet been identified.

Meanwhile, a month earlier, the Dalmatian newspaper Slobodna Dalamcija raised the issue of cruise ships illegally discharging sewage into the Hvar canal. Waste, including excrement and used oil, ends up in the coastal waters of Hvar Island, polluting and degrading the bays. Local activists warn that Croatia’s picturesque beaches could soon turn into a cesspool, but so far authorities have failed to take concrete preventive measures. Paradoxically, despite the fact that the Adriatic has been recognized by the MARPOL Convention as a particularly environmentally sensitive area, decisive action is still only in the realm of international declarations.

Photo. Sergiy Gulenok/Unsplash