Bank erosion control units

Claim 1

Units for controlling erosion of a bank adjacent a body of water due to waves of the body of water striking the bank, which bank extends upwardly from a strand and which units are positioned generally parallel to the shoreline of the body of water, said units comprising a retaining wall means located on the strand and extending generally parallel to the shoreline for restricting material of the bank from progressing into the body of water, means defining a sand-gravel collecting area immediately adjacent said retaining wall means and on the side thereof facing the body of water, said means defining said sand-gravel collecting area comprising structure having surfaces which define a chamber open at the top for receiving water and sand and gravel therethrough and passages for directing water and sand and gravel into the sand-gravel collecting area and from the sand-gravel collecting area toward the shoreline and laterally of said retaining wall and generally parallel to the shoreline, said structure including means for breaking the waves before reaching said retaining wall means and said sand-gravel collecting area, said last-recited means comprising a plurality of wave breakers projecting toward said body of water and from said sand-gravel collecting area against which the waves impact, said wave breakers having respective surfaces facing said body of water and against which waves impact, said respective surfaces being spaced different distances from said retaining wall means.