In general, if you believe your dog is drinking too much water, you should call your veterinary team. They will be able to help guide you as to whether or not the issue is urgent or if it can wait a few days. It can also be helpful to measure your dog’s water intake to confirm.
Sudden and severe changes that are accompanied by other symptoms (lethargy, vomiting, loss of appetite) should be seen on an emergency basis.
If the signs are subtle, gradual, and your dog otherwise is acting like their normal selves, it may be okay to monitor for a few days.
Your veterinarian will typically recommend running a urinalysis (and usually blood tests too) to arrive at a diagnosis. From there, an appropriate treatment plan can be formulated.