Drinking Water Quality Index Germany – A Contextual Overview

Germany has overall good to excellent drinking water. That is the most important message upfront. According to the Federal Environment Agency, over 99 percent of samples comply with the legal limits; for large centralised water supply systems, the authority certifies drinking water quality as good to very good.

The Langwater Drinking Water Quality Index confirms this picture. Even the cities at the bottom of the rankings remain clearly within permissible levels. The ranking therefore does not distinguish between “good” and “bad”, but rather between “very pure” and “still very good, but somewhat closer to the legal limits”.

Methodology of the Index

The Langwater Drinking Water Quality Index is calculated as the average utilisation of legal limits across the five key parameters: lead, uranium, nitrate, nitrite, and fluoride. The lower the value, the purer the water within the scope of this analysis.

Where a city has multiple water utilities, samples from individual providers or available data were used.

PFAS-20 values are displayed additionally in the map but are not included in the score, as these figures come from a separate sampling source (BUND) and are not available as a fully comparable data basis for all cities. The ranking currently includes 59 cities with complete data. Their average index value is 13.23 percent, with a median of 11.51 percent. This means that even the middle of the field uses the legal limits only to a relatively small degree on average.

Where Is the Water Particularly Pure?

At the top of the rankings are Ludwigshafen am Rhein, Neustadt an der Weinstraße, Worms, Hamburg, and Kaiserslautern. Their index values range between 4.7 and 7.3 percent. In simple terms: the measured substances in these cities average only a very small fraction of the legal limits.

It is notable that the top cities include a disproportionately large number of locations from Rhineland-Palatinate, as well as northern German cities such as Hamburg and Kiel, and Lower Saxony industrial cities like Braunschweig and Salzgitter. One explanation could be that Germany’s groundwater resources are distributed very unevenly across regions and depend heavily on the underlying geology and hydrogeological conditions. Particularly productive porous aquifers are found, for example, in the North German Plain, the Alpine foothills, and the Upper Rhine Graben. Such geological zones can create favourable conditions for water extraction, although the specific quality always additionally depends on protection measures, land use, and treatment processes.

Which Cities Are at the Bottom – and What Does That Really Mean?

At the bottom of the rankings are Rosenheim, Emden, Landshut, Mönchengladbach, Koblenz, Heidelberg, Nuremberg, Regensburg, Bamberg, and Bremen (places 50–59). Their index values range from 19.5 to 30.8 percent. While this sounds considerably higher compared to the top cities, it still means: even the lower-ranked cities remain well below the permissible limits for the measured substances on average. By the logic of the index, these cities do not have poor water – they have water that is fully compliant with the law and good overall.

Why Are There Differences in Drinking Water Quality at All?

The differences can be explained to a significant extent by geology, hydrogeology, and the respective catchment area. It starts with the subsoil: depending on whether water flows through sands and gravels, limestone and karst rock, sandstone, or more impermeable solid rock, its natural composition changes. The BGR (Federal Institute for Geosciences and Natural Resources) explicitly states that groundwater resources in Germany are regionally unevenly distributed, depending on the geological subsoil and hydrogeological conditions.

This affects not only the yield but also the residence time, mineralisation, and the natural hydrochemical signature. Human influences add to this. The Federal Environment Agency cites inputs from agriculture as a key factor; in particular, nitrogen-based fertilisation can contribute to nitrate contamination of groundwater. When a city is supplied from a catchment area with intensive agriculture, this can have a stronger impact on nitrate levels than in regions with different land use patterns. Equally relevant is the type of water resource – for example, groundwater, bank filtrate, surface water, or reservoir water.

Why Even Very Good Water Is Not Always Optimal Water

Even very good water – that is, water low in contaminants – is not automatically optimal for every person. First, not all possible contaminants are officially recorded and measured. Second, quality in a practical health sense depends not only on what the water does not contain, but also on what it does contain: water can be very pure and yet provide only small amounts of minerals such as calcium or magnesium. At the same time, the need for mineralisation is not the same for everyone. Depending on diet, life stage, activity level, and individual health circumstances, different compositions and taste profiles may be beneficial.

Minerals influence not only water quality but also, significantly, its taste. This plays a major role in adequate fluid intake, as it has been shown that people drink more when water tastes good – and good hydration is fundamental to health and longevity.

The key, therefore, is balance: as low in contaminants as possible, while at the same time suited to the personal needs of the body.

A Word of Caution: Microplastics

This is where an interesting contradiction in consumer behaviour emerges: although German tap water is of very high quality, many consumers still prefer bottled water. Per capita consumption of mineral and medicinal water in Germany rose to 128.8 litres in 2025. The reason: many Germans are not fully satisfied with the taste and quality of their tap water, or miss the desired level of mineralisation, and therefore purchase expensive premium mineral water in bottles.

However, this is where another problem arises: microplastics. Studies show that bottled water contains, on average, significantly more microplastics than tap water. One study found that a person who drinks exclusively bottled water ingests up to 130,000 plastic particles per year, compared to around 4,000 from tap water. Microplastics have even been detected in glass bottles, often due to abrasion from caps or the bottling process. Those who buy premium mineral water in bottles in the hope of obtaining supposedly purer, more mineral-rich water are often unknowingly consuming a considerable quantity of microplastics.

This Is Exactly Where Langwater Comes In

LANGWATER is a Swiss company that solves a dilemma that every bottled water product has so far failed to address. The starting point is your own tap water, which is filtered using the most advanced available process – reverse osmosis. This reliably removes all residues, down to the smallest particles.

What truly sets LANGWATER apart is the next step: a precise and individually adjustable remineralisation. Pure osmosis water tastes flat, is slightly acidic, and is not suitable for everyday enjoyment – because the high-quality filtration removes everything, including the essential minerals your body needs. LANGWATER’s remineralisation system therefore reintroduces calcium, magnesium, and potassium back into the water in a targeted way, creating a premium drinking experience: balanced, mildly alkaline water with a pH of around 7.8 in the standard setting.

Since minerals shape the taste of water, our water sommelier has developed a proprietary recipe – for a soft, pleasant-tasting water that you enjoy drinking every day. Thanks to the patented dosing system of TheWell 2, the mineral intensity can be adjusted entirely to personal preference and taste.

And all of this completely without plastic bottles – and without microplastics. This makes the water you drink at home truly premium: cleaner than tap water and freer from microplastics than any product on the supermarket shelf. The best of all worlds – pure water, mineralised water, no bottle.

The environmental and economic case is equally clear. Every litre of bottled water consumes petroleum for the packaging, fuel for transport across the country, and your own effort carrying it home – only to dispose of the bottle a few minutes later. LANGWATER makes all of that unnecessary. You save thousands of bottles. And at around €0.12 per litre – compared to €0.50 or more for premium bottled water – the system pays for itself for most households within the first year.

LANGWATER has questioned bottled water, reimagined filtration standards, and created what did not exist before: drinks without a bottle.

“The bottled water and soft drink industry is inefficient and unsustainable. I wanted to change that – for my children’s generation.”
Jan-Erik Lundberg, Founder & CEO

Note: The index was adjusted following a data transfer error. The values have been reviewed and recalculated on the basis of the current data.

Sources

• • Beverage industry – People in Germany are drinking more mineral water (Lebensmittel Praxis, 2026)
• • Consumer study: Mineral water is an established part of drinking culture and a conscious lifestyle (VDM, 2022)
• • Study finds more microplastics in glass bottles than in plastic bottles (Apotheken Umschau, 2025)