German Drinking Water Ordinance for Hotels: What You Need to Know
Operating a hotel means taking responsibility for the drinking water in the building, and that is not a matter of good intentions but a legal requirement. The Drinking Water Ordinance (known in Germany as the Trinkwasserverordnung) sets out specific obligations, and operators who fail to comply are held personally liable. During an unannounced inspection, what counts is not the intention but the record.
At a glance
The four numbers that matter
Who is liable for drinking water in a hotel?
The operator is liable for drinking water quality from the point of handover from the water supplier onwards, and this liability is personal if the system is not operated according to the generally recognised rules of technology. This includes not only the Legionella test but also ongoing operation: water that stands at an outlet for more than 72 hours can lose its hygienic quality, and that is an avoidable risk. Responsibility does not end with installation. It begins there.
For hotels, annual testing is mandatory. The obligation applies once four conditions come together: a large-scale water heating system; showers or other installations where drinking water is aerosolised; supply as part of a commercial or public activity; and that the installation is not in a one- or two-family house.
What does the TrinkwV require in concrete terms?
The test is systemic: at the point where the hot water line branches off from the water heater, at the circulation line, and at the furthest outlets. Samples are taken by an approved testing facility. If the action value is reached, the testing body itself reports this to the health authority immediately; you may learn of the finding at the same time the authority does. Routine results go to the operator, who keeps the record for at least ten years (§ 44 TrinkwV).
The action value is 100 colony-forming units per 100 millilitres of water. This is not a limit in the sense of an acute health hazard, but a clear signal: the system is promoting Legionella growth, and the operator must act. Immediately.
What the result means for a hotel
Once the action value is reached, the clock is running. The operator must clarify the causes, take immediate measures, and report them to the health authority. Filters at the showers can reduce the risk for guests while remediation is underway, but they do not replace eliminating the cause. The full sequence is set out under Legionella in drinking water: what to do after the result.
Action value & § 51 TrinkwV
At 100 CFU/100 ml the clock starts
What does this mean in practice?
A 50-room hotel has at least 50 showers. During high season at 70% occupancy, an average of 15 rooms are empty; in the off-season, or when a wing is closed for winter, easily 30. Each of these showers must be flushed, because otherwise the water stands.
From its PMS, a hotel can see which rooms stood empty, so knowing is the easy part. Flushing them is not. Every outlet has to be opened by hand and run long enough to move the water, and in daily operation that is exactly where it breaks: it costs time, most staff are unsure how long an outlet really needs to run, and when things get busy the step is quietly skipped.
So a task that protects guests ends up depending on whether someone remembers it. That is the dependency Aqvior removes at the shower: every shower is flushed on schedule and every run is logged, so nobody has to keep it in mind. Basins, WCs and kitchen taps keep their own routine.
Legionella & temperature
Where standing water becomes a risk
The second challenge is documentation. The health authority requires proof that flushing actually took place. A sheet of paper with someone's tick mark is worthless during an inspection if it is incomplete. Inspectors arrive unannounced, and what counts then is what can be proven.
How can this be solved?
There are three technical approaches. Manual flushing according to a schedule costs time and staff. Central flushing stations flush automatically, but only at the risers, not at the shower, where the water stands and the risk is greatest.
The third approach is automatic hygiene flushing directly at the shower, and this is exactly where Aqvior comes in. The Aqvior surface-mounted shower fitting with integrated hygiene flushing detects when 72 hours have passed since the last use, and then flushes automatically, precisely at the shower, where the water stands and the risk is greatest. The system is self-powered and needs no electrical connection. Every flush is documented automatically and can be downloaded as a compliance report. Aqvior is retrofitted without opening walls, in under an hour per shower, which is why it fits hotel operations without interrupting the business.
Frequently asked questions
At what level must the health authority be informed?
At 100 CFU/100 ml the technical action level is reached. The operator has to inform the health authority without delay, have the cause investigated and draw up a risk assessment. The notification falls away only if you hold proof that the approved testing laboratory has already made it (§ 51(1) no. 1 TrinkwV). The duties are triggered as soon as the level is reached, not only once it is exceeded.
How high can the fine be?
Up to 25,000 euros per breach. The penalty provision is not in the ordinance itself: § 72 TrinkwV refers to § 73 IfSG, which sets the range. What it comes to in a given case is for the competent authority to decide, by severity and duration.
Where are samples taken in a hotel?
The test is systemic rather than spot-check: where hot water leaves the heater, in the circulation line, and at the outlets furthest away. That is what makes it possible to tell whether a finding affects the whole installation or only a single riser.
Does automatic flushing replace the annual test?
No. The annual test stays mandatory, however reliably the flushing runs. Flushing keeps the water moving and so prevents the problem, but it is not evidence about water quality. The two belong together, and neither replaces the other.
Sources
- Bundesministerium für Gesundheit (2023): Trinkwasserverordnung (TrinkwV) – § 31 Untersuchungspflichten in Bezug auf Legionella spec. (in German)
- Bundesministerium für Gesundheit (2023): Trinkwasserverordnung (TrinkwV) – § 51 Handlungspflichten des Betreibers in Bezug auf Legionella spec. (in German)
- Bundesministerium für Gesundheit (2023): Trinkwasserverordnung (TrinkwV) – § 53 Anzeigepflicht und Meldepflicht der zugelassenen Untersuchungsstelle in Bezug auf Legionella spec. (in German)
- Bundesministerium für Justiz: Infektionsschutzgesetz (IfSG), zuletzt geändert 2023 – § 73 Bußgeldvorschriften (in German) (fine: § 72 TrinkwV in conjunction with § 73 (1a) no. 24, (2) IfSG)
- Umweltbundesamt (2025): Empfehlung des Umweltbundesamtes: Durchführung einer Risikoabschätzung in Bezug auf Legionella spec. gemäß § 51 Trinkwasserverordnung, as of 13 October 2025 (in German; supersedes the 2012 recommendation on Gefährdungsanalyse)
- VDI (2023): VDI 6023 Blatt 1 (2023-09) – Hygiene in Trinkwasser-Installationen (in German)
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The content of this article is for general information and does not replace legal, technical, or health-related advice in individual cases. Information on Legionella and associated health risks is general in nature and constitutes neither medical advice nor an assessment of a specific drinking water installation. For implementation in your operation, clarify your specific situation with the responsible Gesundheitsamt (local public health authority). This article contains links to Aqvior products.