if it's like my D90, there is a battery that is attached to one of the circuit boards inside the camera. when this battery is replaced , the blinking should stop. however I am not sure that this will solve your water damage , the battery should have been taking out immediately after it came out of the water. don't give up right away, someone gave me this camera because it was dropped in a lake and he attempted to dry it out with the rice method but it was jammed so he put away for some time. when I opened it up there was some rice that prevented the shutter from working, once the rice was removed, it started working.
good luck