The sight of Lake Qaraoun, one of the largest artificial lakes in Lebanon, turning green has alarmed the villagers of the western and southern Bekaa Valley who rely on its waters for irrigating their fruits, vegetables and wheat crops.

The lake, created in 1959, suffers from industrial pollution from the factories on its banks, as well as medical waste such as bags of vaccines and needles, and agricultural pesticides. This is why the Litani River Authority launched a floating platforms project in Lake Qaraoun in 2018 to combat toxins in the water and limit the growth of harmful algae, but it did not end the pollution. The project was implemented with a $400,000 donation from the Netherlands. Previously, the Council for Development and Reconstruction oversaw the Lake Qaraoun Pollution Prevention Project, but the cleanup efforts of the Litani Basin were not enough.

The lake, which is also used for the generation of electricity, started turning green in July.

The change of color is caused by the increase of cyanobacteria in the lake, a bacteria that damages marine life, affects fisheries and causes skin diseases and liver cancer, Kamal Salim, a researcher at the National Council for Scientific Research and professor at the Lebanese University, told Al-Monitor.