Don’t know who came up with the recommendations for 8, eight-ounce glasses of water per day which would equal 64 ounces. There is no research to support this recommendation.
An easier method is to pay attention to the color of your urine each time you urinate. (Urine that has accumulated in your bladder during sleep will be more concentrated and yellow. Otherwise, if your kidneys didn’t concentrate urine during sleep, you would have to wake up to urinate.) After the urinating the first time after waking up, your urine should be light yellow and odorless for the remainder of the day. This assumes that you have normal functioning kidneys and no bladder disease or infection. However, paying attention to the color or your urine in the toilet only works in the US as European toilets use less water to flush.
FYI, within 15 minutes of eating asparagus, you may notice a particular smell to your urine. It is harmless and comes from a natural chemical found in asparagus called methylthioacrylate and methylthiopropionate.