Pool Deck Drainage — Why So Many AZ Decks Pond Water
A pool deck that ponds water after a rinse was installed without thought. Here's the slope spec, the drain spec, and the fixes.
The slope spec
¼" per foot away from the pool coping is the minimum. Less than that and water sheets back toward the pool, undermining mastic and pushing dirt under the coping. Confirm with a level before any tile or coping is set.
Where the water goes
Two options: sheet flow off the deck edge into landscape, or channel drain at the low point piped to daylight. Sheet flow is cleaner if grade allows; channel drain (Stegmeier, NDS) is required when the deck is bordered by walls, walks, or doors.
Why decks pond
Most common: deck poured flat to chase a 'level' look, then everyone wonders why puddles form. Second: drain installed but the line clogged because no cleanout. Third: settled fill under part of the deck pulled the slope downhill years later.
Fixing a deck that ponds
Spray-deck overlay can add ⅛–¼" of slope if existing concrete is sound. Severe ponding usually means cut-and-replace a section. Adding a channel drain after the fact requires saw-cutting and piping — budget $1,800–$4,500 depending on length.
