The abbey of Bizere was one of the numerous medieval monasteries active in the valley of the Lower Mureş (Western Romania) at various times, attested in several written sources but also by its archaeological remains ca. 15 km west of Arad on a former island. The documentary sources indicate that the abbey was dedicated to the Virgin and used by Benedictine friars. It was built ca. 1100. The first written source, dated to 1183, shows the abbey in full activity. The buildings were ruined after the mid-sixteenth century and drastically despoiled. After first excavations in 1981, further digs at the abbey took place between 2001 and 2009. Many parts of the former building complex were identified, mainly in the eastern part of the island, near a dried-up branch of River Mureş. The present article focuses on the remains of a lavabo discovered in 2004 among the ruins of the former abbey. The author presents their archaeological context of discovery and the remains of the water supply system, she establishes the period when the fountain was used (in the end of the twelfth century), and provides a hypothetical graphical reconstruction. The latter is based on the traits of the discovered stone fragments and through analogy with Western European fountains from cloisters and settlements or baptismal fonts dated to the twelfth and thirteenth centuries. The lavatorium, neighbouring channels and water tower are only part of the system of water management in Bizere, which further research may identify more precisely and on a wider scale.