In the decision of November 22, 2018, GZ: DSBD122.956/0007-DSB/2018, the data protection authority had to deal with the admissibility of a smart water meter that continuously recorded water flow and water temperature and stored this data daily in the form of minimum, average and maximum values for an extended period of time. The complainant asserted his right to confidentiality and argued, among other things, that there was neither an objective justification nor a legal basis for the installation of smart radio water meters and that the respondent had therefore unlawfully installed such a water meter, not least despite the complainant’s express objection. The respondent, on the other hand, based the collection and management of meter data on the legal basis of Art. 6 para. 1 lit. b, e and f GDPR. The data protection authority upheld the complaint, holding that interference by the respondent pursuant to Section 1 para. 2 DSG always require a legal basis, since the latter is constituted as a body under public law and is therefore a state authority under leg. cit. is qualified. An appeal to the lawfulness of processing based on Art. 6 para. 1 lit. b and f GDPR is therefore not permissible. However, neither the Measurement and Calibration Act, the Drinking Water Ordinance nor the Water Act 1959 provide a corresponding legal basis for the use of smart water meters, as is regulated for the electricity sector in the Electricity Industry and Organization Act 2010, for example. The installation and operation of the smart water meter by the respondent therefore constitutes an unlawful interference and violates the complainant’s right to confidentiality under Section 1 of the Data Protection Act. The decision is not legally binding.