Can I Drink Tap Water in Istanbul?

Istanbul's tap water is treated by ISKI to meet WHO, EPA, and EU standards at source, with chlorination and filtration treatment. However, experts and locals recommend bottled water for drinking due to aging distribution pipes, high residual chlorine, and secondary contamination risks from building water tanks. Water is safe for brushing teeth, cooking, and showering. Bottled water costs as little as $0.15 per liter and is widely available throughout the city.

Istanbul's water supply is managed by ISKI (Istanbul Su ve Kanalizasyon Idaresi), which treats water from surface sources including the Omerli-Darlik system on the Asian side and the Terkos-Alibeykoy system on the European side. Nearly 97% of Istanbul's drinking water comes from surface water reservoirs. The water undergoes chlorination and filtration at treatment plants before distribution, and according to ISKI's official water quality reports, the treated water meets international standards for microbiological, chemical, and physical parameters. However, water quality deteriorates during distribution through aging infrastructure. Many Istanbul buildings have rooftop water storage tanks that can introduce secondary contamination through bacterial growth and sediment accumulation. The city's aging pipe network can contribute iron rust, turbidity, and organic contaminants. ISKI reports also note that some reservoirs are exposed to pollution from unsanitary settlements, though treatment processes address most contaminants at the source. The primary concern for visitors is the heavy chlorination applied to ensure microbiological safety, which creates an unpalatable chemical taste. Despite meeting safety standards, locals overwhelmingly use bottled water or water delivery services. This preference reflects concern about the distribution system reliability rather than treatment efficacy at the plant level.

While Istanbul's tap water meets international safety standards at the treatment plant, it is not recommended for direct consumption by visitors. The combination of aging infrastructure, secondary contamination from building water storage systems, and heavy chlorination makes bottled water the safer and more pleasant choice. Bottled water is inexpensive (typically $0.15-0.30 USD per liter), readily available at every store and restaurant, and preferred by local residents. For short stays, exclusively drinking bottled water eliminates health risks. For longer stays, consider installing a reverse osmosis filter in your accommodation.