After a recent storm, Guardian Group, Inc. was asked to inspect a damaged seawall in a south Florida commercial marina to determine the cause and origin of the reported damage, and to provide estimated costs of repair. The marina provides both wet and dry storage facility for boats-the dry storage sheds were built in the late-nineties, while the seawall and wet storage dock slips were originally installed in the late 1970’s. The marina also neighbors a section of condominium buildings.

Typical concrete seawall construction consists of precast concrete panels adequately hammered securely into a soil bed. Additional panels are placed to form the concrete cap-which also holds the tie-back rods for anchoring. Guardian’s expert researched the weather data at the time of the storm-it was noted that the maximum sustained winds at the property topped out at 55.17 mph, and gusts were as high as 78.56 mph. Rainfall total was 4.86 inches, and there was 0-feet storm surge.  There was however a reverse storm surge condition in the area-the storm effects caused water levels to drop significantly lower than predicted levels.

During his inspection, the Guardian engineer discovered key conditions that helped solidify his recommendations to the client. There were broken tie-back rods in the area of the collapse which compromised the lateral load capacity. It was also noted that the neighboring condominium complex didn’t have gutters installed to redirect storm water runoff away from the marina; further increasing the intensity of the loading on the seawall at areas near the buildings.