Is Tap Water Safe to Drink in Chiang Mai?
No, tap water in Chiang Mai is not safe to drink. The Chiang Mai Provincial Waterworks Authority treats water from the Ping River, but ageing pipes and secondary contamination make the supply unreliable for drinking.
Water Source
Chiang Mai’s municipal water is sourced from the Ping River and Mae Kuang Dam, treated at the Provincial Waterworks Authority facilities. Some outlying areas rely on mountain spring catchments and community-managed water systems.
Contaminants & Concerns
Water leaving the treatment plant generally meets Thai standards, but the distribution network introduces rust, sediment, and bacterial contamination through old, corroded pipes. Agricultural runoff from upstream farming contributes pesticide residues to raw water. During the burning season (February–April), ash and particulate matter can affect surface water sources.
Tips
- •Drink bottled water or use a quality filter — refill stations offering purified water for 1–2 baht per litre are ubiquitous
- •Avoid ice from unknown sources, though most restaurants and bars use commercial ice from purified-water factories
- •During the smoky season (Feb–Apr), even filtered water may have off-flavours from particulates
Frequently Asked Questions
Sources & References
The safety rating and guidance on this page draw on the following sources. See our full methodology.
- •WHO Guidelines for Drinking-water Quality
- •CDC Travelers' Health destination pages
- •The municipal water utility's published quality data