Converting a Failed Retaining Wall into a Stable Slope

From Cinder Block Wall to a Safe, Mowable Hillside

After removing a failing cinder block retaining wall, a homeowner wants to create a rolling hill instead of a 5-foot drop.

Slope Ratio Guidelines

• 2:1 (2 horizontal : 1 vertical) = minimum for stability with vegetation. For a 5-ft drop, you need 10 ft of horizontal run.
• 3:1 or flatter = required for a mowable slope. For 5 ft drop, that's 15 ft of run.

Execution Options

• Small area (<30–40 ft long): Doable by hand with helpers—move soil, grade to ratio, compact, seed/sod.
• Larger area: Hire a grading contractor with a bobcat for a half-day; cost-effective and precise.

Critical Steps

1. Grade to the chosen ratio (2:1 or 3:1).
2. Compact in lifts to prevent future settlement.
3. Establish vegetation immediately: hydroseed, erosion control blanket + seed, or sod.
4. Divert runoff from the top with a swale or gutter extension to protect the new slope.

Check local codes—some municipalities require engineered plans for slopes over a certain height.