Slope, bank and bed protection

Reclamations directly adjacent to open water (marine and coastal waters) require carefully designed and constructed shore protection measures to defend the new land against hydraulic attack (currents, waves). Banks and beds of canals, channels, ditches, outfalls and other types of open surface drains (inland waters) constructed on or adjacent to the reclamation may have to be lined to prevent scour. Depending on the type of structure, the future development, the magnitude and intensity of hydraulic loading and the level of damage that is considered to be acceptable, various options exist to protect the reclamation area  

Information on the physical site conditions required to design an appropriate protection include, see Chapter 3 and Appendix B  

The most appropriate type of protection depends on many variables including hydraulic, economic, environmental and climatic conditions. In general, the protection has to be more robust if the severity of the hydraulic loads increases. 

If no slope protection is applied then natural gentle slopes develop which may be subject to the erosive action of currents and waves. Depending on the exposure to wave action and its grain size, beach slopes in sand may vary between 1 20 and 1 50 (Wiegel 1964, CUR 130). Slopes not exposed to waves may be stable at 1 4 to 1 6 for longer periods of time. Undesirable erosion should be compensated with beach nourishment works. 

Preservation of existing coral reefs or sand bars near the reclamation area may reduce the wave energy and/or deflect (tidal) currents and can therefore be an attractive solution both from an environmental and aesthetic point of view. 

---