Ayamama Creek, which flows into the Marmara Sea, has turned an unusual black and blue color, something blamed on pollution, according to locals. The creek, which crosses through Istanbul’s Küçükçekmece, Bağcılar and Bahçelievler districts on the European side, is surrounded by heavily populated areas and factories.

Göktuğ Aktan, a local living near the creek, said it sometimes becomes "green or red." According to Aktan and others, the color change is the result of discharge from textile workshops located near the creek, while the Istanbul Metropolitan Municipality (IBB) continues its efforts to rehabilitate the creek and its banks.

Along with the unnatural color, locals complain of a strong odor emitting from the creek. Anadolu Agency (AA) reported that the creek was polluted with wastewater from canals connected to Ayamama.

Atılay Öznur, who lives near the creek, said the waste in the creek was emitting a stench and although the authorities had closed down the connection of canals filled with waste to the creek, they had been "opened" later.

The color change is quite common in bodies of water, mostly stemming from natural causes like algae blooms, but in Istanbul, creeks and streams like Ayamama occasionally experience a change in color due to heavy industrial activity and the dense population crammed into a relatively small land area growing each year. Last year, Istanbul's Haramidere creek was subject to almost a daily change of color, something blamed on untreated waste dumped into the creek by nearby factories.