The ecological balance of the lake, which is popular with tourists, is acutely threatened. Algae, which arise as a result of environmental pollution, are to blame.
Mostar - turquoise blue water, bordered by green forested hills - the Jablaničko Jezero (57th place), about an hour's drive from Sarajevo, the capital of Bosnia and Herzegovina, is considered one of the most beautiful lakes in Europe. Most recently, the 30 kilometer long and up to 70 meter deep reservoir even made it into a ranking of the best beaches in the world, the so-called Golden Beach Awards 2024.
Water in the reservoir is turning brown - a sign of its poor condition, according to experts
Now, however, environmentalists are warning that the reservoir, which is so popular with tourists at home and abroad, is at serious risk. This can currently be seen from the fact that the once turquoise lake water now appears brown.
According to experts, the unusual discoloration of the lake suggests that its ecological balance has been permanently affected. “It is an algae bloom that is caused by excess phosphates and nitrates in the lake as well as increased water temperatures,” explained Amir Variščić from the “Zeleni Neretva Konjic” (Green Neretva Konjic) association in an interview with the Austrian news portal
Today.at
.
Algae plague in Jablaničko Jezero is not occurring for the first time
What is striking is that the algae bloom occurs every spring and once again puts the ecosystem of the Jablaničko Jezero to a tough test. But how do high concentrations of nitrates and phosphates get into the lake water?
According to Variščić, this is mainly due to waste from the metal industry and agriculture - in the latter, pollution with artificial fertilizers plays a particularly important role. A small part of the contamination is said to come from feces from nearby households. Reason enough for the environmental protection association to now describe the Jablaničko reservoir as a “horror lake” in the media. Is sustainable travel still possible?
Experts warn of further pollution of the reservoir – and of a lack of oxygen in the water
The pollution of the Jablaničko Jezero indicates the ecological problems that exist in Bosnia and Herzegovina.
Sanel Riđanović, head of the biology department at the teachers' college at the University of Mostar, told
the Austrian online magazine
Kosmo that the brown color of the lake has been repeating itself for years as a result of algae blooms caused by pollution.
Sanel Riđanović, head of the biology department at the teachers' college at the University of Mostar, explains the background: “This situation has been repeating itself for years. The phosphorus usually found in detergents promotes algae growth. Two years ago I pointed out that the primary source of pollution must be found.”
It is suspected that municipal wastewater disposal in Konjic or industrial facilities could be the causes of the pollution. “Without sufficient oxygen in this water, massive fish deaths are to be expected,” warns Riđanović.
Warnings from environmental activists about pollution in the Jablaničko Jezero have so far gone unheeded
Environmentalist Variščić confirms a sad record: never before has the extent of the algal bloom been as enormous as this year. “Although algae are not directly dangerous to humans, their presence leads to extremely high oxygen consumption in the water, which severely affects the aquatic flora and fauna,”
Kosmo magazine quoted him as saying.
In the fight against further pollution of the Jablaničko reservoir, environmentalists have a difficult time. Their suggestions for more effective measures to reduce environmental pollution have so far gone unheard. There is also currently a law in Bosnia and Herzegovina that allows companies that do not have sewage treatment plants to continue to discharge their wastewater into bodies of water.
“If the industry in Konjic continues to expand, the situation in Lake Jablanicko is unfortunately very likely to worsen,” warns the environmental activist. In addition to the microscopic algae, larger species known as “water glasses” have already appeared and are overgrowing the shore regions. This indicates an already long-term impairment of the ecological balance.
(fh)