There are a couple of ways to remove water marks from wood. White toothpaste seems to have the best results. Simply rub it on with a cloth for a few minutes until you see results. See the full instructions and other methods here.
How to remove water stains / rings from wood furniture! This works! I tried every other thing on the Internet and failed! This worked within minutes!!! I had a huge water heat stain from a hot pot on a wet cloth!
Recipe for removing Water Stains and marks from furniture: Olive Oil Table Salt Mix the olive oil and the salt in a bowl to make a thick paste. Then, simply rub the paste onto the damaged area. I made mine pretty thick, and just sat it on the areas where I had damage. Leave sit for approximately :30 minutes, and wipe all excess paste off of furniture. All of the stains will magically be gone!