Can I Drink Tap Water in Mexico City?

Mexico City's tap water is NOT safe to drink directly due to widespread contamination from outdated infrastructure and groundwater quality issues. While SACMEX (the city's water authority) treats water at treatment plants, approximately 25-26% of the water supply is lost in leaks through aging pipes, and storage tanks often remain uncleaned, allowing residual chlorine to dissipate and microorganisms to multiply. About 80% of Mexico City residents use bottled water exclusively. Approximately 70% of Mexican citizens nationwide avoid tap water due to safety concerns.

Mexico City's water supply faces multiple challenges rooted in aging infrastructure and groundwater depletion. The Sistema de Aguas de la Ciudad de México (SACMEX), established in 2003, is responsible for water treatment and distribution, operating under Mexico's environment ministry (Semarnat) and the regulatory oversight of COFEPRIS (Federal Commission for Protection Against Sanitary Risk). The city relies primarily on groundwater sources, which have become increasingly contaminated with natural and industrial contaminants. The primary water quality issues stem from several factors: First, significant water loss occurs during distribution—approximately 25-26% of the city's water supply is lost through leaks in the 13,000 km of potable water pipelines. Second, open and inadequately maintained water storage tanks prevent residual chlorine from remaining effective, allowing bacterial regrowth. Third, water treatment plants apply chlorination, filtration, and flocculation processes, but research on SACMEX wells reveals that free chlorine is frequently found below the 0.2 mg/L minimum recommended by Mexican regulations. In fact, 44 out of 107 wells studied tested positive for fecal coliform bacteria, which should be completely absent in treated drinking water. Groundwater contamination in Mexico City includes high levels of fluoride and coliform bacteria, particularly in areas affected by industrial activity. In 2024, residents of several Benito Juárez neighborhoods reported foul-smelling water caused by industrial oils and lubricants, with some residents experiencing skin and eye problems. Heavy metals including aluminum, iron, and manganese exceed established limits in numerous wells throughout the distribution system. The city's water infrastructure continues to deteriorate despite ongoing maintenance programs.

Mexico City's tap water is not suitable for drinking without treatment. Bottled water (agua embotellada) is widely available and inexpensive (around $0.77 USD per liter at convenience stores), making it the practical choice for all visitors. Even luxury hotels cannot guarantee tap water safety due to city-wide infrastructure issues. Always maintain a supply of bottled water, and when eating out, specify 'sin hielo' (without ice) for beverages. If you experience diarrhea or digestive issues, they may be due to water quality adjustment rather than contamination. Consider a portable water filter or UV purification bottle for additional peace of mind, and if staying longer than a few weeks, invest in a home filtration system.