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<br />DISADVANTAGES: 1) <br /> <br />Baskets subject to rust and deterioration If not coated against <br />carros Ion. <br /> <br />2) limIts use of riverfront. <br /> <br />3) Basket cost high If purchased already constructed. <br /> <br />NOTES: Prefabricated baskets have been marketed in Europe for many years; however, <br />baskets for the construction of bank protection works In the United States have been used <br />widely only In the past 15 years. The basic element of the basket works Is the cage. The <br />cage Is a rectangu I ar w r re-mesh structure d 1 v I dad by d t aphragms Into ce II s. The mesh Is <br />generally galvanized steel wire, which Is coated If It is to be used in a corrosive <br />anv Ironment. The baskets can a I so be of homemade var J ety and the tota I project can be <br />done over a period of time dependIng on the funds and man-hours available. <br /> <br />COSTS: Assuming 1-1/2 cubic yards at $47/cublc yard, the cost equals $70/bank-foot. <br /> <br />MAINTENANCE REQUIREMENTS: The life ot rock-filled wire basket protection depends on the <br />durability of the wire. Replace broken wires wIth galvanized or plastic coated wire. The <br />baskets occasionally are IJDved during severe storms, but can often be replaced. Such <br />movement indicates foundation failure or scour at the toe. Repair all storm damage as <br />quickly as possible. <br /> <br />ENVIRONMENTAL ASPECT: The major advantage of rock-fl I led wire baskets Is that they can be <br />designed and placed In forms that are physically and visually compatible with the <br />surround I ngs. Another advantage Is that because the rock Is conta I ned with I n wi re <br />Inclosures, they can be placed at steep angles, requiring disturbance of only a minimum <br />width of shoreline. This feature Is particularly beneficial where space is limited such <br />as In urban areas, recreational developments, and sensitive environmental areas. A third <br />advantage is that 5011 and other debris accumulate in the openings between the rocks which <br />form the cages. Vegetation will become established In the soil and further help them <br />blend into the environment. Vegetation growing on the baskets provides some wi Idllfe <br />habitat, and where they extend underwater the rocks provide attachment sites for benthic <br />organisms. These benthic organisms In turn provide food for fish. <br /> <br />, <br /> <br />22 <br />