Warning signs include visible lean or bulging, horizontal or stepped cracking, water pooling or damp patches instead of draining through weep holes, and cracking or sinking in the ground above the wall. Get a structural assessment promptly if you notice any of these.
Retaining walls rarely fail without warning. Catching these signs early can mean the difference between a simple repair and a full, expensive replacement.
Visible lean or bulging
Any forward lean or bulging in the wall face is a sign the wall is being pushed beyond its capacity — this should be assessed promptly.
Cracking
Horizontal cracks can indicate bending stress; stepped or diagonal cracks in masonry can indicate movement or settlement.
Water pooling or damp patches
Water sitting behind or seeping through the wall (rather than draining through weep holes as designed) suggests a drainage problem building up pressure.
Ground movement above the wall
Cracking or sinking in the ground, paving or lawn above the wall can indicate the wall or the retained soil is starting to move.
What to do
If you notice any of these signs, get a structural assessment promptly — early intervention is almost always cheaper than waiting for a full failure.