Indirect Techniques for Erosion Protection
8.1.3 IMPERMEABLE DIKES
The relative merits and faults of impermeable dikes as compared to permeable dikes
were discussed in 8.1.2. Impermeable dikes can be built of the following materials:
Earth, sand, or other material faced with armor;
Bags or tubes filled with sand or grout;
Walls of steel, wood, or concrete piling;
Wooden cribs filled with earth or stone;
Stone and gabions are the most commonly used of these materials. Although some
of these materials are not truly impermeable, dikes constructed of them have permeabilities
low enough that the amount of flow which passes through the structure is negligible.
Discussion of the general characteristics of most of these materials is provided in Chapter 7.
Typical impermeable dikes are shown in Figure 8.2.