Abstract. This article assumes the establishment of clear standards, the use of certified sampling and analysis techniques, and the use of verified measuring instruments and reference materials. The introduction of a system of normative, methodological and metrological support for water quality control makes it possible to obtain reliable and comparable results of water quality control, timely identify sources of pollution, and make informed management decisions. The creation of a network of accredited laboratories and the harmonization of national standards with international requirements contribute to increasing the competence of personnel, improving data exchange and mutual recognition of results at the international level.