Gabions are wire fabric containers, uniformly partitioned, of variable size, interconnected with other similar containers and filled with stone at the site of use, to form flexible, permeable, monolithic structures such as retaining walls, sea walls, channel linings, revetments and weirs for earth retention.
Soil erosion is an ever present problem and gabions have proved to be a lasting solution around the world. The earliest known use of gabion-type structures was for bank protection along the Nile River during the era of the Pharaoh. In the subsequent 7,000 years since its initial use by the Egyptians, the gabion system has evolved from baskets of woven reeds to engineered containers manufactured from wire mesh. The lasting appeal of gabions lies in their inherent flexibility.
Gabion structures yield to earth movement but maintain full efficiency and remain structurally sound. They are quite unlike rigid or sem-rigid structures which may suffer catastrophic failure when even slight changes occur in their foundations. Highly permeable, the gabion structures act as self draining units which "bleed" off ground waters, relieving hydrostatic heads. Interstitial spaces in the rock fill dissipate the energy of flood currents and wave action.
Efficiency in gabion structures, rather than decreasing with age, actually increases. During early periods of use, silt and vegetation will collect with the rock fill to form a naturally permanent structure and may be used to remove solid pollutants or "floatables" from the water.