That actually depends on where you live* and on your preferences**:
*Every nation has different traditions. Some are known for drinking more water, some are known for drinking less water, etc. Plus, depending on the climate from the region you live in, it is recommended to drink more or less water.
**Some people drink less water, some drink more, and some don't even drink water. This is a taste and routine factor.
Some experts say you should drink half an ounce of water per pound you weigh (per day, that is). Others say similar amounts, but base themselves in different factors and scientifical evidence.
Now, if you multiply that by the number of days in a year:
0,5oz * 365 = 182,5oz of water per year.
Hope it helped,
BioTeacher101