I'm not sure what your question is really, if it's "Is bump mapping useful for water" then I'd say that it depends on what kind of water you're doing. If you're rendering some fairly flat surface (such as a lake) then yes, bump mapping is very useful (though, not a silver bullet on its own). Bump mapping is covered in many places on the internet a simple google search should give you plenty of information.
From the rest of your post, it sounds like you're not using shaders which will limit visual quality you can achieve. Water rendering consists of both reflected and refracted components based on the the angle between the viewer and the surface normal (for more information on this, you should research the fresnel equation).
To make things more complicated, the depth of the water at the view->surface point should be taken into account when building the final color. There are other things to consider also, but it depends what kind of level of visual representation are you trying to achieve.
For more volatile surfaces, such as oceans, bump mapping alone is usually not enough to convey a realistic representation. You should probably investigate displacement mapping or even displacement with tesselation.