Mértola
No. Tap water in Mértola is high risk. Several tests failed: check local advice before drinking.
Is it safe?
CM de Mértola
High risk
Several tests failed: check local advice before drinking
Safe-water score 96.82% in 2025. It was 97.64% in 2024.
Supplied by CM de Mértola.
About 6,041 people. 3,833 tests.
10 E. coli or enterococci failures in the bacteria tests.
Over a limit at least once in 2025: Coliform bacteria, Chloride, Sodium, Chlorate, E. coli bacteria, Arsenic, Nitrate, Manganese.
Hardness: Hard (27 °f).
Source
ERSAR, Portugal’s water regulator (RASARP 2026).
Period covered: 2025.
Covers all 278 municipalities in mainland Portugal. The safe-water score is the share of required tests that were done and met the legal limits in 2025. 99% or above is rated low risk. Hardness is the typical level measured by the main supplier.
Common questions
Can I drink the tap water in Mértola, Alentejo?
No. Tap water in Mértola is high risk. Several tests failed: check local advice before drinking.
Where do these ratings come from?
ERSAR, Portugal’s water regulator (RASARP 2026). Period covered: 2025.