Parking Lot Maintenance Overview
Standing water in commercial parking lots is more than an inconvenience — it accelerates asphalt deterioration, creates slip-and-fall hazards, and signals drainage deficiencies that will worsen over time.
Common causes of parking lot drainage problems: inadequate initial grading (insufficient slope toward drainage structures), settled or heaved pavement that creates low spots, blocked or failed catch basins, inadequate drainage infrastructure for the lot size, and tree root intrusion into drainage pipes.
Why Regular Maintenance Matters
Minimum slope requirements: parking lots should maintain a minimum 1.5-2% cross-slope toward drainage structures. Flatter areas collect water; steeper areas cause erosion of pavement edges. Proper initial grading is foundational — poor grading can't be fully corrected without reconstruction.
Catch basin maintenance: catch basins collect surface runoff and direct it to the storm sewer system. They require regular cleaning (annually in most cases) to prevent silt, debris, and gravel from blocking inlet grates and pipes. A blocked catch basin turns a manageable drainage system into a flooding one.
Commercial Parking Solutions
Surface patching for low spots: minor depressions that collect water can sometimes be addressed with infrared repair to re-establish positive drainage slope. Major settled areas require base repair and resurfacing.
Trench drains and linear drainage: for lots with persistent concentrated drainage problems, adding trench drain channels directs water to catch basins more effectively than surface runoff alone.
D&D Commercial Services provides catch basin cleaning, drainage assessment, and parking lot grading solutions for commercial properties throughout Ontario.