Is your retaining wall keeping your home safe and secure from rising water? Or is it helping keep the slope of hill spilling onto the road? Retaining walls are used to keep different level of soil separate most likely an elevated hill from a road. They also keep a river that runs through a city from running over the city. If there is a bulge or crack in the wall the retaining wall could be becoming destabilized. For example water fluctuation and/or pressure variation can begin to destabilize the wall and cause problems.