Drainage Problems: How to Identify and Solve Them

Invisible but Costly

Drainage problems are among the most insidious in landscaping. Water pooling near your foundation causes leaks, mold, cracks and destroys outdoor work. In Quebec, with heavy precipitation and spring snowmelt, good drainage is essential.

Warning Signs

Outside: puddles lasting 24+ hours, soggy spots, moss, erosion, yellow or thin sod in low areas, efflorescence on foundations, sinking patio or driveway pavers.

Inside: basement damp or mildew smell, water stains on walls, foundation cracks, peeling paint, efflorescence on concrete.

Common Causes

• Grading — slope should be ≥2% away from the house for the first 6 feet
• Gutters and downspouts — must discharge 6+ feet from the foundation
• Clay soil — drains poorly

Solutions

1. Re-grading — $500–$2,000, best paired with new sod 2. French drain — $2,000–$6,000, needs careful excavation 3. Dry well — $1,000–$3,000 4. Rain garden — $1,500–$4,000

When to Call a Pro

Water inside, foundation damage, major re-grading, foundation drain, municipal system involvement, or when you can't identify the source.

Landscaping and Drainage

A good landscaper integrates drainage everywhere: proper pavers slope, sod on graded soil, raised beds, retaining walls with drainage, and carefully positioned patios and fences.

Groupe Altia evaluates drainage on every project and proposes integrated solutions — excavation, French drain, dry well or rain garden. See our projects · Free quote.