You should be drinking 2 - 3 litres of water everyday.  

Before you say I can't stand water. Have you tried adding a slice of lemon or lime to it.

If you are drinking herbal/fruit teas this is part of your fluid intake.

You should be drinking more if  exercising or in hot weather.

If our body is even slightly dehydrated it puts extra demands on the liver to help the kidneys out instead of it doing its job of metabolizing fat.

I find with majority of my clients on my Kick Start Fat Loss programmes when their weight stays the same I always ask the question ARE YOU DRINKING ENOUGH FLUIDS? Usually they have let this slip and they start to see a difference when they increase their fluid intake once again.