It depends upon how high you want backfill against the pool wall. My install left me with 3 feet banks around much of the pool. I didn't want that much wet soil lying against my pool wall, so I decided to widen my trench, retain the dirt with timbers, and grade the trench to drain to one end where it could exit with the surrounding terrain. I then topped with a few inches of river rock to prevent washing out. Works well and I sleep well during the wet winter/spring, not worring about standing water and a sinking pool. You don't need the timbers, but you could grade the trench so you don't have a bowl, make sure one end drains to the natural slope, and backfill with rock.