I cannot say for your location..

but in the UK water and gas pipes are equipotentially bonded to the supply earth usually via the main earthing terminal in a consumer unit (or to an earth rod in a TT system).
So if the impedance of the water is low enough ,the fuse/protection "should" blow/trip to disconnect the circuit.
If the fault current is not high enough to blow/trip the fuse/protection then it will develop a potential divider effect where risk of shock becomes greater the closer to the fault you are.

More modern consumer units with RCCDs built into them will trip when the Phase/Neutral imbalance is greater than 30mA