Photoshop :: Replacing Tile Around A Pool Under A Waterfall

For the orange ring pic:

I was thinking about grabbing the luminosity of the waterfall and putting it above the replacement tiles. (Using various forms of blending.)

here are the samples and what I did. (i know the tiles are not distorted properly. I was trying to get the see through effect of the water first.)

I've never done this type of thing. (I've read about it before.) I want to make it look good since I won't be at this temp job long and I want to make a good impression. (So they will ask for me to come back later on.)

For the patio pic:

i'm not sure what to do about the shadows. I'm thinking of the same technique for the water edge. And I will be using 2 different tiles to replace the existing ones.