Oh no, that is not a good thing. I was afraid of the water when I was a boy and my dad just tossed me in the pool. Sink or swim he said! I would NEVER do that. I think you just ease them into the water. Get in with them and show them it's safe. Let them hold your neck for a while if they need to. Also get a life jacket on them so they can see they are safe and won't go under.
Last year my daughter was afraid of the pool. She was only 1 but cried constantly when we tried to get her in there. This year so far she has done well. We really have not done much other then giving her bathes. I would gently get them used to it.
Anyone I have ever known with a fear of the water had the fear due to something traumatizing. A big pool or lake can be intimidating to a small child, but if you're holding on to them and taking your time they should get used to it.
I like any place related to water, be it swimming pools, rivers, lakes or seas. I guess my children inherit the nature as none of them has issues being in water.