PWN drinking water: quality, hardness and price

Reading time: ~12 minutes

What is PWN?

PWN is the drinking water company of Noord-Holland. It supplies tap water to almost the entire province, from Texel and Den Helder to Alkmaar, Hoorn, Haarlem, Zaanstad and the Haarlemmermeer. You cannot choose who supplies your water: your postcode decides. If you live in Amsterdam or immediately around it, Waternet (the Amsterdam water utility) is your supplier and not PWN.

That combination of water and nature is not a coincidence but engineering. PWN treats part of the water in the dunes itself: pre-treated IJsselmeer water is infiltrated into the dunes near Castricum and Heemskerk, sinks through the sand and is filtered there naturally. Managing the dunes is therefore also managing a treatment plant.

Customers themselves are satisfied. Nationally the Dutch rate the drinking water from their water company at 8.3, and PWN customers give the water in Noord-Holland an 8.5 according to PWN. That is the highest mark you will come across in this file, and it is immediately the reason why the rest of this article is not an alarm story.

As with the water quality of Vitens, with the drinking water of Oasen in the Groene Hart and with the drinking water of WMD in Drenthe, the same applies: the national average says little about your own tap. At PWN that is especially true, because the company works with five different supply areas.

Where does PWN drinking water come from?

From surface water, and that makes PWN an exception. In the Netherlands, according to the RIVM, roughly 60% of drinking water comes from groundwater. At PWN it is exactly the other way round.

• 92% of the water PWN treats is surface water. Of that, 75% comes from the IJsselmeer and the rest from the Lekkanaal.
• 8% comes from ground or dune water, abstracted in the Gooi and in the Noordhollands Duinreservaat.

That difference is not academic. Surface water is open to everything that ends up in it upstream: run-off from land, discharges, deposition from the air. Groundwater sits under tens of metres of soil and is therefore better protected. PWN says so plainly on its own tariff page: surface water is of poorer quality than groundwater and takes more energy to treat.

The result is that PWN runs one of the heaviest treatment chains in the country. IJsselmeer water arrives at Andijk, in the dunes near Castricum and Heemskerk part of it goes through natural soil passage, and at Heemskerk the membrane filtration is being extended to push back PFAS further, among other things. What each filter technique does and does not hold back is set out in the overview of what the various water filters remove from surface water.

The five supply areas of PWN

PWN does not publish the composition of its drinking water as one national figure, but per supply area. There are five of them, and each area gets its own analysis from Het Waterlaboratorium (a Dutch water laboratory) four times a year.

Why this matters: most people who look up their water hardness are shown a provincial average. At PWN you can retrieve the real figure for your area, including the measurement date. The page on the composition of the drinking water has the reports ready per quarter and per year. If you would rather have a national picture per municipality, that is in our overview of water hardness per municipality.

How hard is PWN water?

On average 7.9 degrees of German hardness. That is soft water, and PWN calls it that on its own questions page too.

Compare that with Drenthe or parts of Brabant, where the water comfortably exceeds 12 °dH and limescale is a daily subject. How the hardness classes relate to one another is explained in hard water in the Netherlands. And if you live in a part of the area where you do see limescale rings, the explanation at filtering limescale out of your tap water will help.

One warning about the figure 7.9. It is an average across the whole province. Your supply area can differ from it noticeably, and that is precisely why PWN publishes the quarterly reports per area. For an exact figure, always go to the report for your area, not to the average.

What does drinking water cost at PWN in 2026?

A cubic metre costs €1.98 including 9% VAT. On top of that come the standing charge and the tax on mains water. These are the tariffs PWN has set for 2026.

Work it out for an average household using 100 m³ per year. Consumption costs 100 times €1.98, which is €198.00, the standing charge is €97.12, and the tax on mains water with VAT comes to around €47.60. Together roughly €343 per year, or about €28.50 per month or a good €3.40 per cubic metre all-in.

Per litre that is roughly €0.0034. That figure is worth remembering, because it is the benchmark against which every other way of drinking water is measured. How that calculation works out in the rest of the Netherlands is set out in what a cubic metre of water costs, and how many litres actually go into a cubic metre you can read at how much 1 m³ of water is.

Why is the cubic metre price at PWN higher?

It is higher, and PWN gives an honest answer for it itself. The company mainly uses surface water from the IJsselmeer and the Lekkanaal. That water is of lower quality than the groundwater many other water companies work with, the requirements for drinking water keep getting stricter, and together that means more energy per cubic metre. More energy means higher costs, and those sit in the variable tariff.

PWN rightly adds that a fair comparison looks at the total, so including the standing charge. A company with a low cubic metre price and a high standing charge can work out more expensive for a small household than a company with a high cubic metre price and a low standing charge. For comparison: the standing charge of €97.12 at PWN is lower than the €114.07 that Oasen charges in 2026, while the variable tariff there is lower.

The increase itself comes mainly from inflation according to PWN, plus investments that are already needed now for climate change and population growth. That is not a PWN story but a national pattern.

Is there PFAS in PWN drinking water?

Yes, in very small quantities, and the water meets the statutory standard. PWN reports itself that extremely sensitive measuring methods detect small quantities of PFAS in tap water, and that all Dutch drinking water companies meet the European PFAS standard that came into force in 2026.

Two figures are getting mixed up, and that is the heart of all the confusion about this subject.

And here it becomes specific to Noord-Holland. PWN draws the distinction itself: tap water made from groundwater generally meets that stricter guideline value, but tap water from surface water not always everywhere. Because 92% of PWN water comes from surface water, that is a relevant nuance for this area and not for, say, Drenthe.

Holding two things true at once is the only honest position here. The water is safe: according to the RIVM the health-based limit value is not exceeded through tap water alone, and the contribution from food is three times larger than that from drinking water. At the same time the RIVM advises bringing total PFAS intake down, and PWN is working on that itself by extending the membrane filtration at Heemskerk. Which technique actually holds PFAS back is set out per method at PFAS filtering and which technique works, and where PFAS has been measured in the Netherlands you can see on the PFAS map of the Netherlands. More background on filtering PFAS is at water filter against PFAS.

Pharmaceutical residues, chlorine and taste

Pharmaceutical residues. They are present, just as in almost all Dutch tap water made from surface water. PWN adds a clarifying figure: to take in the amount of one paracetamol tablet through tap water, you would have to drink two litres every day for 685 years. That is not playing it down but giving a sense of scale, and it is the reason why pharmaceutical residues in the Netherlands are an environmental question and not an acute health question. What else is known about it is at filtering pharmaceutical residues out of tap water.

Chlorine. Dutch drinking water companies do not disinfect with chlorine, unlike in many other countries. You can taste that, and it is one of the reasons why Dutch tap water scores so well in blind tests. More on that in filtering chlorine out of tap water.

Taste. Water from the IJsselmeer that has passed through dune sand tastes different from deep groundwater from Drenthe. Neither is wrong; they differ in composition. What filtered water is exactly and how it differs from ordinary tap water is explained at what filtered water is exactly.

What PWN does not control: your own pipes

The responsibility of a drinking water company stops at the water meter. Behind that meter your own installation begins, and there are three things there that no treatment plant solves for you.

Lead pipes. In homes built before 1960 they may still be in place, and the old city centres of Haarlem, Alkmaar and Hoorn are full of pre-war building stock. Soft water also dissolves metals slightly more readily than hard water. Replacement by a certified installer is the only real answer; what lead does and how you keep it out is at filtering lead out of tap water.

Standing water. PWN advises running your taps for one minute after being away for a week or longer. Water that has stood in a pipe for a long time takes up taste and substances from that pipe. How long water stays good in a jug or bottle is at how long you can keep tap water.

Boil water notice. After a burst main or after works, a water company may temporarily be unable to fully guarantee quality, and then the advice to boil water follows. That is something other than an outage with no water at all. What you do in both cases is at a boil water notice for tap water and at no tap water and what to do then. A water filter never replaces a boil water notice: NSF 42, 53, 61 and 372 are about chemical substances and materials, not about microbiological treatment.

Do you need a water filter in the PWN area?

No. We would rather say that ourselves than have you read it somewhere else. PWN drinking water meets all statutory requirements, including the European PFAS standard, the water is soft, and customers give it an 8.5. A blog from a filter shop telling you this water is no good deserves your suspicion.

Why people in Noord-Holland filter anyway comes down to three reasons, none of which is about safety.

• The source: 92% surface water means PWN has to remove more than a company on deep groundwater, and that tap water from surface water, according to PWN, does not always stay below the stricter RIVM guideline value for PFAS everywhere.
• The house itself: a pre-war home, a flat with a long riser, or an installation you simply do not know the age of.
• The sum of it all: the RIVM advises bringing total PFAS intake down. You have little grip on your food, but you do on your tap.

What our filter does is follow the order PWN itself uses: purify first, then add back. The filter that adds minerals removes more than 100 contaminants from the water in five stages, including PFAS, microplastics, heavy metals, fluoride, nitrate and pharmaceutical residues, and then returns calcium, magnesium and potassium via Swedish Mineral Rock™. A domestic reverse osmosis system usually skips that last stage, and then you are left with bare water. Why that matters is at reverse osmosis water, healthy or unhealthy.

If you are unsure about where it goes in the kitchen, the comparison of a water filter system on or under the worktop will help. If you have a Quooker, it is worth knowing that it heats the water rather than purifying it; what does and does not go together is at water filter and Quooker.

Comparison: what the options deliver

The PureFilter Mineral+ costs €149.00 including the first filter. A replacement filter costs €65.00 and lasts about twelve months for 1 to 3 people, and about six months for 4 to 6 people. The duo with two cartridges costs €115.00. Converted, that is less than one cent per litre. If you would rather not think about it, the Filterplan sends the cartridges out automatically and on time for €48.00 or €86.00 per delivery. How often replacement is needed is at how often you replace a water filter.

At PureFilter we see that customers from Noord-Holland rarely call about limescale, which is exactly what you would expect at 7.9 °dH. They call about PFAS, about an old house in a city centre, or because they read that their water comes from the IJsselmeer. Installation takes 5 to 10 minutes: you do not need a plumber, you use one pair of water pump pliers to connect it to the cold water pipe, and you change the cartridge later with the supplied key. Step by step, that is in the guide to installing a water filter. An overview of water filters you mount under the worktop is in the webshop, and how the various models compare is at the best water filter.

Looking up your water composition yourself

The figures in this article apply to the PWN area as a whole. Your town belongs to one of the five supply areas, and those differ from one another. Here is how to go about it.

• Go to the page on the composition of the drinking water and choose the report for your supply area, per quarter or per year.
• The measurements come from Het Waterlaboratorium, which examines the water of PWN, Dunea and Waternet daily.
• If you only want the hardness figure, the average of 7.9 °dH is on the questions page of PWN.
• Submitting a meter reading, viewing an invoice or reporting a fault is done through Mijn PWN. This article is not the place for that, but the PWN customer service is.

One tip that is often skipped: do not only look at the hardness, but also at how much water you drink per day. That determines how heavily every figure in this article weighs for you. Work it out at how much water you need per day.

Frequently asked questions

Conclusion

PWN drinking water in Noord-Holland is soft, meets all statutory requirements and is rated 8.5 by customers. What sets PWN apart is the source: 92% surface water from the IJsselmeer and the Lekkanaal, where the rest of the Netherlands runs mainly on groundwater. That explains both the heavier treatment and the higher variable tariff, and PWN says so openly itself.

The figures to remember: hardness averaging 7.9 °dH, €1.98 per cubic metre plus €97.12 standing charge and €0.437 tax per cubic metre in 2026, together roughly €343 per year at 100 m³. PFAS stays below the statutory standard of 100 nanograms per litre, but water from surface water does not, according to PWN, always reach the stricter RIVM guideline value of 4.4 everywhere.

That last sentence is the whole trade-off in one line. Filtering in the PWN area is not something you do because the water is bad, but because you want to decide the last few metres, from water meter to glass, yourself. And if you do, the order that counts is the same one PWN keeps to at Heemskerk: purify first, then add back.