Tap water quality in Portugal remains above 98% for the 11th consecutive year.

 

This value is the result of combining the mandatory analyses (99.91%) and compliance with the parametric values ​​(98.93%).

Last year, mainland Portugal had a tap water safety indicator close to 100%, marking the 11th consecutive year since then, according to data released this Tuesday by the Water and Waste Sector Regulatory Authority (ERSAR).

According to this year’s Annual Water and Waste Services Report (RASARP), regarding 2025, 98.84% of tap water is safe, a figure obtained by combining the number of mandatory analyses (99.91%) with compliance with parametric values ​​(98.93%).

With the data now available, it has been 11 consecutive years in which the water quality indicator has been at 99%, according to the report accessed by Lusa, which indicates that safe water at the pump level (collection, treatment and transport to municipalities) maintains a value of 99.69%, while safe water at the pump level (distribution to consumers) shows a value of 98.84%.

Susana Rodrigues, director of the quality department at ERSAR, says there are “some problems” with smaller systems, and adds that larger systems offer greater safety, partly because they are more professionalized.

Last year, 74,473 analyses were carried out on the water supply, all of which were scheduled, and of those, only 229 (0.31%) were incorrect.

In the low-pressure safe water system, 392,667 analyses were carried out (99.1% of the planned total), and 4,235 (1.07%) were non-compliant, a figure partly explained by poor quality in some public fountains.

Compared to the previous year, the percentage of safe water increased from 98.86% in 2024 to 98.84% in 2025. The number of municipalities with water quality equal to or greater than 99% remained the same (225, or 81%), and 42 municipalities (15%) recorded 100% safe water (five fewer than in 2024).

There are still 51 municipalities with safe water quality above 95% but below 99%. This number is identical to that in 2024.

According to ERSAR’s maps, the best results (equal to or greater than 99%) occupy most of the country, with the exception of some regions of Alentejo and municipalities in the central and northern interior.

Most non-compliances relate to pH (31%) and microbiological parameters (38%), due respectively to natural characteristics of the water and failures in disinfection systems.

Two municipalities marked in “red” did not exceed 95%: Marco de Canaveses and Fornos de Algodres.

In the first case, the lowest value relates to analyses of water from public fountains, which, according to Susana Rodrigues, should not even be used since they coexist with tap water, which is of “excellent quality”.

In Fornos de Algodres, it was merely an administrative matter related to the expired certification of the analysis technician.

“The essential message is that there is no such thing as unsafe water,” said the official during the report’s presentation, pointing to the importance of municipalities connecting to high-pressure systems.

Vera Eiró, president of the Board of Directors of ERSAR, also argued that “what provides the most guarantee is a connection from a low-pressure system to a high-pressure system,” adding that the trend is for municipalities to be more coordinated, centered on a joint entity.

According to ERSAR, only 62 municipalities are vertically integrated, responsible for both the high and low pressure water systems, and there are still 180 public fountains as the sole source of drinking water, serving 8,797 inhabitants.

In the interior of the country, in the downturned sector, are the systems that are most difficult to manage, with more supply zones.

If a municipality has many supply zones, often managed by parish councils, it can lead to “non-compliance with microbiology standards,” so ideally these locations should be connected to high-pressure systems, emphasized Susana Rodrigues.

The official also explained that new analysis parameters were introduced last year, but that there was no drop in quality.

Last year, ERSAR carried out 60 inspections of management entities, issuing fines to 32 (especially for failures in the disclosure of data), and ASAE carried out 128 inspections of private water supply systems.