There is little to no chance the cylinder will fill fully with water.
I have it happen on a V8, where the electric fuel pump filled one piston with petrol. ( the ignition was on, with a stationary engine, and the valve did not close on the one SU).
I tried to start, but the starter motor could not turn the engine.
No damage occurred, and all was well after the fuel had been drained.
I would suspect the same would be the case with the 1.8.