One dog walks toward the shared bowl. The other stands over it, freezes, or growls. Do not wait to see whether they "sort it out." Move the dogs apart without reaching into a conflict, then provide water in separate safe areas. Each dog needs reliable access that does not depend on getting past the other.
Put several bowls in places where a dog can drink without being cornered. Separate the dogs with doors or secure gates when you cannot supervise. Check that a dog is actually drinking enough, if either seems unusually thirsty, stops drinking, or this behavior appeared suddenly, arrange a veterinary check. After a fight or bite, seek veterinary care for injuries and qualified behavior support before letting the dogs share the area again.
Look beyond the bowl
Dogs Trust notes that conflict between dogs can involve food, toys, attention, resting places, or other resources. Watch whether the same dog blocks hallways, guards a person, or becomes tense near meals. Keep valued things separate while you understand the pattern. Do not remove water to make the resource less important, and do not punish a growl, it is a warning that helps you prevent escalation.
A behavior professional can help assess distance, layout, and safe reintroductions if needed. Do not stage repeated approaches to the bowl as training. The first aim is ordinary daily life in which both dogs can drink peacefully, even if they always use separate stations. After ensuring both dogs have safe, separate access to water, the resource-guarding guide can help you understand guarding. Do not stage approaches to the bowl.
Sources: Dogs Trust: Resource guarding in dogs. Dogs Trust: Introducing a new dog to your current dog.