Water is one of the key blocks in ZS. You can use it to travel vertically very quickly and it can be used to your advantage if you can use it well. However, I am sure that there has been a time when you are 2 to 4 blocks away from an incoming zombie and you decide to go in a water elevator.
DON'T!
When you enter water, it has a short delay until you start to ascend, and this can allow the zombie to infect you. You might think that if the jump before you go in the water it will give you a boost, but if the zombie does this it makes no difference.
If you desperately need to go into the water, make sure you are at least 6 blocks away from the zombie, with good ping. The number of blocks needed between you and the zombie depends on your ping. If you are not sure that you can make it up the water without the zombie chasing you, you should try to juke the zombie, leading it far away before you either gain enough space to go into the water. But overall, don't go into water unless 1) There are no zombies 2) You have a safe number of blocks in between you and the zombie 3) You want to get infected, in which you should just not move.