If the dog repeatively drinks water and immediately vomits, then there is the possibility of an intestinal obstruction.

If not then there is something that is exciting the small intestine to reflux up. Also stomach irritation resulting in reflux could get yellow bile to come up. In this case you might want to call the Vets and ask what the dosage would be for an acid blocker such as rantidine (Zantac). Might take upwards to an hr to work - if it does.

Certainly heading for the Vet if it continues is prudent. They can stop the vomiting with metoclopromide or Zofran, and/or they might prescribe Metronidazole to help clear up any intestinal inflamation.