As discussed in the "How to avoid your pool turning into a boat" post, the project requires a great deal of drainage:
This post covers drainage locations 1, 2 and 3.
The pool deck trench drain sits against the rear wall and slopes gently towards an outlet at the stair end of the deck.
The pool deck itself will slope towards the rear wall, providing fall for pool and rain water to drain off the deck. It's important for the pool deck to slope away from the pool itself. If the deck slopes towards the pool, then rain and splashed pool water will drain back into the pool, taking all of the dust and dirt present on the pool deck with it. It's also likely to lead to the pool overflowing if the pool deck is large relative the the area of the pool and heavy rains are not infrequent.
To secure the trench drain in place, a thin layer of concrete is placed beneath and around it.
With drainage in place, the deck is now ready for it's final surfacing.