There are many reasons why a retaining wall can fall over. In our industry most, if not all, manufacturers of interlocking block have cross-section sheets on how tall of a wall you can build with their block - in good soils (gravels and sands) and with level compacted backfill. Many times installers will exceed those recommended heights, or there ends up being a slope above the retaining walls which adds a significant amount of extra pressure. If this is the case you have three options:
This question is often asked by many home owners.
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