Context. The presence of water has long been seen as a key condition for life in planetary environments. The Cassini spacecraft discovered water vapour in the Saturnian system by detecting absorption of UVemission from a background star. Investigating other possible manifestations of water is essential, one of which, provided physical conditions are suitable, is maser emission. Aims. We report detection of water maser emission at 22GHz associated with several Kronian satellites using Earth-based radio telescopes. Methods. We searched for water maser emission in the Saturnian system in an observing campaign using the Mets?hovi and Medicina radio telescopes. Spectral data were Doppler-corrected over orbital phase for the Saturnian satellites, yielding detections of water maser emission associated with the moons Hyperion, Titan, Enceladus, and Atlas. Results. The detection of Saturnian water molecules by remote astronomical observation can be combined with in situ spacecraft measurements to harmonise the physical model of the Saturnian system. Key words: masers - radio lines: solar system - planets and satellites: general
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