Tap water in Portugal: where the national statistics end

ERSAR's open municipal dataset covers 23 years, from 2002 to 2024. Funchal, Machico, Câmara de Lobos, Santa Cruz and Calheta do not appear in a single one of them. Madeira has never been part of the national drinking water statistics.

For the Azores, the break can even be dated. Ponta Delgada, Angra do Heroísmo and Horta appear in the data up to 2009 and drop out from 2010. ERSAR itself gives the reason: Decreto Legislativo Regional 8/2010/A of 5 March 2010 established the regional authority ERSARA (Entidade Reguladora dos Serviços de Águas e Resíduos dos Açores). Responsibility for water quality in the Azores passed to it.

So anyone reading a national rate for Portugal is reading a mainland rate. It tells you nothing about a holiday on Madeira or São Miguel. Spain, by contrast, includes its islands in the national dataset. That does not mean the island suppliers measure any worse; they simply report somewhere else.

99.57% is the 2024 median share of analyses that comply with the limit, calculated across the 278 mainland municipalities. 196 of them are at 99% or higher. Two are below 95%: Tondela at 93.29% and Marco de Canaveses at 94.27%.

ERSAR publishes three figures for each municipality. First, the proportion of the analyses in the monitoring plan that were actually carried out. Second, the proportion of analyses within the limit. Third, the “safe water” indicator derived from these. 270 of the 278 municipalities fully completed their analysis programme in 2024.

In 2002, the picture was different. Across the 294 municipalities recorded at the time, the median “safe water” indicator was 83.93%. 64 municipalities had fewer than 95% of their analyses within the limit; in 2024, there are two. Portugal built up its drinking water monitoring over two decades; it did not inherit it.

369 chlorine samples were taken by EPAL (Empresa Portuguesa das Águas Livres) from consumers' taps in Lisbon in the first quarter of 2026, with a maximum value of 0.84 mg/l. The same number, 369 samples, were tested for coliform bacteria and Escherichia coli, with 5 and 1 exceedances respectively.

Together with faecal streptococci, turbidity, iron and nickel, this makes 11 non-compliant results in the quarter. What matters is where EPAL locates them. The supplier found nothing unusual in the distribution system. For the germs, it cites a lack of maintenance or cleaning of the domestic pipes and tap as a possible cause. For iron and turbidity, it points to worn pipes and low consumption. For nickel, it suspects migration from the material of the pipe or tap.

The other values are unremarkable. Nitrate is 1.82 to 3.13 mg/l, against a limit of 50. Lead reaches a maximum of 7.8 µg/l, against a limit of 10. The sum of 20 per- and polyfluoroalkyl substances (PFAS) remains below 0.0015 µg/l, against a limit of 0.10. All 20 pesticides tested, including glyphosate, were below the limit of quantification of 0.030 µg/l. For raw water, EPAL runs separate monitoring programmes, one for surface water and one for groundwater.

99.53% in the public network, 99.59% at the consumer's tap: Porto publishes two reports for the same quarter, and the difference between them is the interesting part. The figures come from the fourth quarter of 2025 and cover 500,000 people.

In the public network, the supplier counted 32 non-compliances, mostly for coliform bacteria, which achieved a compliance rate of 96.55% across 840 samples. Escherichia coli did not appear in any of the 840 samples. At the tap itself, 6 deviations remained. Follow-up analysis did not confirm 83% of them. The report attributes the remaining 17% to a lack of maintenance of the domestic pipes. The owners are responsible for this.

Porto has harder water than Lisbon. At the tap, conductivity ranges from 151 to 271 microsiemens per centimetre and total hardness from 4.5 to 6.9 °dH. Nitrate stays at 3.4 to 4.4 mg/l, trihalomethanes at 27 to 38 µg/l, and manganese at no more than 20.3 µg/l, against a limit of 50.

Every deviation was reported to ERSAR and to the health authority. According to the report, the authority saw no risk to human health in any of the cases.

54 reports for the first quarter of 2026 have been published by Águas e Resíduos da Madeira (ARM), one for each supply zone or transfer point. For Lisbon and Porto combined, there are three over the same period. So Madeira is documented in finer detail, just outside the statistics that everyone quotes.

The main system for Funchal has 1.5 °dH, plus a conductivity of 89 to 129 microsiemens per centimetre. No other drinking water tested here is softer. Chloride is below 10 mg/l, nitrate below 1 mg/l, trihalomethanes at 15.3 µg/l. Escherichia coli and coliform bacteria remained at zero in 18 samples.

Within the city, the picture changes with the zone. The borehole on the Ribeira de João Gomes delivers 6.1 °dH, up to 401 microsiemens, 83 mg/l chloride and 44 mg/l sodium. Four times as hard as the main system, from the same urban area.

The zones also differ when it comes to chlorine. The main system measures 0.4 to 1.0 mg/l in 18 samples, the Engenheiro Amaro da Costa treatment plant 0.8 to 1.5 mg/l. Lisbon stays below 0.84 mg/l in 369 samples.

80 µg/l of trihalomethanes is the maximum value that Portimão's municipal supplier (EMARP) measures at the consumer's tap, against a limit of 100. The value is higher than anything reported by Lisbon, Porto or Funchal, and it has a twin: chlorate at 1 mg/l, against a limit of 0.25.

Both are by-products of disinfection. A single analysis breached the chlorate limit and was reported as an exceedance in the first quarter of 2026. The microbiological side remained clean: Escherichia coli and coliform bacteria were at zero in 44 samples each. Total hardness is 1.7 °dH, nitrate 4.2 mg/l, chloride 47 mg/l. Bromate reaches 8 µg/l against a limit of 10, aluminium 57 µg/l against 200.

Faro obtains all its water from the regional supplier Águas do Algarve. The municipal utility (FAGAR) distributes it via 574.86 km of network and 19 reservoirs to 41,595 customers, averaging 18,519 m³ per day. Faro publishes current individual values only as an image file, which is why the municipal value is given here.

The column shows the share of analyses within the limit, from the ERSAR dataset for 2024. Three rows are marked “not in the dataset”.

1.5 to 6.9 °dH is the range across all the places measured here. In Germany, water below 8.4 °dH is considered soft. Every Portuguese place tested is below this, and in the glass such water tastes thin.

Calcium accounts for most of this. Funchal measures 5.3 mg/l, Portimão 5, Lisbon 14.5 to 26.6. Magnesium stays in single figures everywhere, at 2.58 to 4.21 mg/l in Lisbon and 2.7 in Portimão. Sulphate is also low, at no more than 28.4 mg/l in Lisbon, against a limit of 250. Little calcium means little limescale in the kettle, but also little taste in the glass.

The second factor is disinfection. Trihalomethanes form when chlorine comes into contact with organic material in the raw water. In France, the same process shapes the taste even more strongly. Portimão reaches 80 µg/l, Lisbon 67, the main system in Funchal 15.3. The least is formed where groundwater flows: the borehole in Funchal comes in at less than 0.5 µg/l.

10 to 20 millilitres of water get into your mouth when you brush your teeth, a fraction of a glass. In Portugal, there is nothing against using tap water for this, at any of the places tested here.

It pays to look closely at a different point. The weak spot is rarely the network; it is the last few metres before the tap. That is exactly where EPAL and the Porto supplier locate their germ findings, and exactly where the water in a hotel room or holiday flat often stands for days.

In practice, this means: run the tap briefly until the water feels noticeably cooler, then brush your teeth, drink, make coffee. For ice cubes and salad, the same applies in Portugal as at home.

On 25 July 2026, Decreto-Lei 149/2026 came into force, published in the Diário da República of 24 July 2026. It amends Decreto-Lei 69/2023, with which Portugal had transposed the European Drinking Water Directive 2020/2184.

The reason for it is unusually openly documented. In infringement procedure 2025/2068, the European Commission had found that the Directive had not been fully transposed into Portuguese law. The new version is intended to complete the transposition.

For travellers, one point is concrete. Some public fountains are fed by a single spring and do not meet drinking water requirements. There, the supplier must provide an alternative no more than 200 metres away. A second date falls shortly before this. Portuguese suppliers have only had to monitor PFAS, bisphenol A, haloacetic acids and uranium since 12 January 2026, according to the Porto report. Accordingly, the report gives the figure zero for PFAS in the fourth quarter of 2025.

Keep the hot water tank above 60 °C: that is the recommendation of Faro's water supplier in its leaflet on standing water. Three further points come from the same source, and they describe the situation in holiday accommodation precisely.

• After a longer absence, let the water run until it has been renewed.
• If the plumbing is old and the water has a yellowish to brownish tinge, run it off in the morning and look into replacing the pipe with non-corroding material.
• Clean and disinfect shower heads, humidifiers and whirlpool baths regularly, i.e. all devices through which legionella can get into the air we breathe.

A holiday flat may well meet every condition for stagnation: old pipes, weeks of standing empty, a warm climate. The supplier is responsible for the water up to the meter; from there on, it is down to the building.

3 attributions of cause in the Lisbon quarterly report point to the domestic plumbing, and a fourth in the Porto report on consumers' taps. A filter on the tap therefore acts exactly where the documented deviations arise.

Two cases are relevant for Portugal. The first is the bacteria from unused pipes, which EPAL found five times in one quarter in Lisbon. The second is taste: activated carbon binds chlorine and its by-products, which reach up to 80 µg/l in Portimão. For the nickel measured, too, EPAL sees the material of the pipe and tap as a possible cause.

What a filter in Portugal does not need is a contrived reason. Nitrate and lead are well below the limits at all the places examined here. Pesticides and PFAS remained below the limit of quantification in Lisbon. Through the European directive, the same values also apply in Germany.