istercian monasteries were built in close proximity to a water source. One of the reasons was the Cistercian diet: the Cistercians did not eat meat, so they had to grow and breed fish themselves. For fish farming the system of three ponds was used. Three ponds exist near the Padise Monastery, at Valkena (Kärkna) two ponds have been found, there is a well-planned extant system of canals there. Water was also used as an energy source for the water mills and sawmills or other hydraulic systems. The Cistercians were leaders in hydraulic engineering in the Middle Ages. The monasteries made use of an elaborate water system inside the buildings as well: clean water was provided in the kitchen for cooking and in the lavatory for washing hands, filthy water was conducted into a wastewater canal.
