The question is why is your dog drinking so much water? There are lots of reasons why a dog could drink excessive amounts of water. Some are benign and some are more serious than others and so it is always a good idea if your dog is drinking excessive amounts of water is to get your dog checked by a veterinarian. They'll usually want to do a urinalysis and/or some blood work as well to determine if there are any underlying problems. Now what could those problems be? Well there are lots of them. The most common one being urinary tract infections, kidney infections or bladder infections are very very commonly associated with dogs drinking more water to naturally kind of flush themselves out. Other reasons could be kidney problems that would be more serious, also dietary means can do that as well. Too much sodium or salt can also lead to excessive thirst, dehydration of course could cause them to drink excessive amounts of water and so as you can see there are multiple reasons and causes for drinking too much water so get your dog checked out first and make sure that everything is o'kay.