BT MQ 4a(36) :כיון דקא משכא ואתיא מימר אמ׳ אי לא שתיא לחד יומא תשתי לתרי תלתה יומי‏ : since it flows continuously he surely would say that if it does not have enough irrigation in one day it will be irrigated in two or three days
See the entire entry for šty vb. to drink