About a month ago there was alot of snow in the area but it got really warm outside and everything melted turning the streets to swimming pools. I had no choice but to drive through an area that was fairly deep and ever since there has been a loud kind of whining noise from the engine , It happens all the time no matter if im in neutral in gear etc... The engine is completly stock no mods whatsoever..Everything is fine performance wise but just loud as hell... Any ideas what could be wrong??

Car is 97 Civic Si (EX in US)