Wastewater released from a preliminary treatment facility operated by the Istanbul Water and Sewage Administration (ISKI) on Sunday has caused visible discoloration in the Marmara Sea and spread a strong odor along the shoreline between Küçükçekmece and Avcılar, renewing concerns over coastal water quality and environmental protection.
Water discharged from the rear canal of the Küçükçekmece Preliminary Wastewater Treatment Plant during the afternoon and evening hours changed the color of the sea along the Avcılar coast within a short time. The affected shoreline turned brown, and an unpleasant odor spread across the surrounding residential areas.
Aerial images documented the extent of the discoloration, showing the spread of polluted water along the coastline.
The Küçükçekmece facility, operated by ISKI, has a daily treatment capacity of 354,000 cubic meters and a flow rate of 120,829 cubic meters. The discharge originated from the canal opening directly into the Marmara Sea at the rear section of the plant.
The incident again highlights persistent environmental pressures on the Marmara Sea, which faces ongoing challenges associated with urban wastewater, industrial activity and coastal development.
Environmental specialists emphasize that uncontrolled wastewater discharge poses risks to marine ecosystems, particularly in semi-enclosed seas such as the Marmara, and underscore the need for enhanced monitoring and sustainable water management practices to safeguard Istanbul’s coastline.
