Discharging a lot of clear fluid can be normal depending on where you are in the menstrual cycle. Around ovulation, more clear discharge is produced, which changes the pH environment of the vagina and allows sperm to travel to the uterus for fertilizing an egg. If you are on birth control or not trying to get pregnant, you will still experience these discharge changes as a normal part of the menstrual cycle.
If you are not around the time of ovulation and notice a sudden increase in clear discharge, consult a healthcare provider. In rare cases, it could mean that something is irritating the vagina or cervix (such as leaving a tampon in and forgetting about it).