Why Retaining Walls Bulge

When a retaining wall begins to bulge, professional work must be done to stabilize and correct this hazard.  A bulging retaining wall is a very dangerous hazard on your property, and depending on the location, can cause serious, even deadly damage if it suddenly collapses.

Retaining walls begin to bulge because the hydraulic pressure in the soil behind the wall becomes too great for the wall to sustain.  The causes of this can be a combination of factors.

  1. The Freeze/Thaw cycle throughout winter and early spring – As snow melts into the soil behind the retaining wall, it may re-freeze in the soil before it can completely drain, causing the soil behind the wall to expand and push on the wall.
  2. Inadequate Footers/Foundation – If the original installation of the retaining wall was done improperly, there is a chance that the footer or foundation laid below the wall was not WIDE enough to accommodate the forces the wall must withstand to hold the amount of soil behind it.  Even if the wall itself is stable and well built, if the footers were not poured wide enough, the wall is prone to collapse due to an inadequate foundation.  The rule of thumb is that the foundation of the wall must be at least 8″ to 10″ WIDER than the wall to prevent the wall from leaning and bulging.
  3. Soil Settling – Over time, especially in our region where a freeze/thaw cycle happens several times a year, the soil will settle and become too compacted.  At this point there is too much weight behind the wall, and the pressure behind the wall is more than the wall can sustain.

Retaining walls can bulge for one of these reasons, or a combination of these.  If you notice bulging in your retaining wall, or if you notice that during a “thaw” there is NO seepage from your retaining wall, please contact the professionals at Herstad Landscaping right away for help.  We will work you into our schedule as soon as weather conditions permit safe conditions, and we can help you prevent an expensive and potentially deadly disaster on your property. Al and the team are here for YOU! Contact us today.