ABSTRACT
Surface intakes Offshore submerged intakes, which are located at some distance from the coast and in greater water depth where marine life is less abundant, often produce a better feed water quality with lower contents of suspended solids and microorganisms than near shore intakes. They are the prevailing intake type for SWRO plants and are typically placed in 10-15 m water depth and 2-5 m above the seafloor (see Table 5 for examples). Depending on the seafloor bathymetry, this may require a distance of several hundred meters from the shore [22]. The seawater transmission pipeline from an offshore submerged intake to the shore can either be placed on or below the seabed, using open-trench or tunneling techniques. Intakes which are located directly at the shoreline, which is common for distillation plants but also seen in some SWRO plants, are often protected by a jetty or breakwater basin in order to reduce wave action and to allow suspended material to settle.
