/resources/condo-parkade-drainage-inspection
Parkade drainage inspection, before the wet season tests it for you.
Below-grade drainage is the one system in a building where the consequence of failure is immediate and total. It is also the system most likely to be silted, undersized, or quietly out of service.
Resources/Parkade
Why below-grade drainage carries outsized risk
Everywhere else in a building, drainage failure produces a slow problem. Below grade it produces water with nowhere to go, in a space that usually contains vehicles, electrical equipment, mechanical rooms, and storage.
The system is also mostly invisible. Pits, pumps, and buried lines are not on anyone's daily path, so condition is assumed rather than known until an event proves otherwise.
The checklist
Slope and ponding. Standing water after rain indicates the deck is no longer draining to the intended points, whether from settlement, coating build-up, or a blocked outlet.
Catch basins and trench drains. Grates clear, sediment removed, and outlets confirmed flowing rather than assumed.
Sump pit and pump. Pit clear of debris, float operation confirmed, discharge line clear, and any alarm or duplex arrangement verified as functional.
Backflow protection. Where present, condition and accessibility, because it is only useful if it can be reached and serviced.
Perimeter and foundation drainage. Evidence of water entering at the wall or slab edge, and confirmation that surface water above is directed away from the structure.
Ramp and entry drainage. The trench at the top of the ramp is the building's first line of defence against surface water arriving all at once.
Frequency and seasonality
Drainage should be reviewed at minimum before the heavy rain season and again after it, because the failure mode is accumulation and the load is seasonal. Sites with heavy leaf fall, construction activity nearby, or a history of ponding warrant more frequent checks.
Quarterly cadence handles this naturally: one review going into the wet season, one coming out of it, and two more that catch anything that changes in between.
What documentation should capture
Record the location of every drain and pit, the date each was checked, whether flow was confirmed, and photographs of anything that has changed. Note maintenance performed and by whom.
That record does two things: it proves the system was maintained, and it makes the next event far easier to diagnose because the baseline is known. Items requiring engineered assessment of capacity or design are referred out with the reason stated.
Common questions about this topic.
- What does a parkade drainage inspection cover?
- Deck slope and ponding, catch basin and trench drain condition, sump pit and pump operation, backflow protection where present, perimeter drainage at the parkade wall, and any evidence that water is bypassing the drainage system entirely.
- How often should parkade drainage be checked?
- At minimum before and after the heavy rain season. Buildings with known ponding, a history of flooding, or heavy leaf and sediment load benefit from more frequent checks, which is why drainage sits in every quarterly review cycle.
- Why does silted drainage matter so much?
- Because a drain that is half blocked works acceptably in ordinary rain and fails in the event that matters. Capacity is only tested under load, and that is the worst time to discover it is gone.
- Is drainage failure an emergency?
- Active flooding is, and it requires the appropriate emergency and trade response. SENTiNEL is not an emergency service. Its role is documenting and prioritizing drainage condition so the emergency is less likely in the first place.
Bring a construction-led record to your building.