Littoral transport

Littoral transport the movement of littoral drift in the littoral zone by waves and currents including movement parallel (longshore transport) and perpendicular (on/offshore transport) to the shore. 

Early in the siting process the investigations should include the collection and analysis of all available historical data on the stabihty of the local shoreline. For sandy or silty beaches it is customary to evaluate the stabihty of the shoreline on the assumption of both the onshore-offshore movement and the littoral transport of beach materials. When the coast is formed by cliffs, changes may occur in the coastline over a long period and may be able to be deduced from historical maps. 

Byrne et Riedel and Gourlay, and Hume and Herdendorf studied the inlet channel stability on sheltered (protected) coasts and demonstrated that larger values of the empiric coefficient C (in accord with Ref 32) and smaller values of n in Eq. (31.7) apply to coasts with limited littoral transport. The aforementioned three studies also indicate that the mean-maximum velocity required to maintain stability of the inlet channel is less (reaching approximately one-third less) than the typical 1 m/s required to maintain a channel on an exposed coast. 

In the absence of littoral transport gradients and other sources or sinks (including sand exchanges with the lower shoreface and backbarrier), the above... 

Consider, for example, the jetty criteria of Section 5.6. Criteria (d) and (e) can limit littoral transport of sediment into the navigation channel, making the channel more reliable and reducing maintenance costs. However, in many sandy coast situations those criteria may produce structures that effectively block longshore sand transport and cause downcoast beach erosion, violating criteria for preserving beaches and protecting coastal property (principles of safety, social values, and sustainability). 

Water used for field irrigation is then transported to littoral lagoons, like in the case of the Badia d Alfacs, where important mussel farms are located (see Fig. 12). 

This chapter summarizes our results from two northern Wisconsin seepage lakes that were chosen to assess the importance of various processes controlling transport of Hg across the sediment-water interface. Total Hg (HgT) concentrations were determined as a function of depth in the solid and dissolved phases of the water column, and in littoral and profundal sediments. New sampling and analytical procedures allowed for the detection of low (picogram) levels of Hg. Measurements obtained in this phase of the study together with those obtained from previously published data on these lakes were used to make a preliminary examination of the relative importance of factors influencing Hg cycling at the sediment-water interface. 

Boehm PD, Barak JE, Fiest DL, Elskus AA (1982) A chemical investigation of the transport and fate of petroleum hydrocarbons in littoral and benthic environments the Tsesis oil spill. Mar Env Res 6 157-188... 

Littoral (or Longshore) Drift/Transportation Movement of material or sediment (usually sand or shingle) along the coastline, caused by waves and currents. 

The longshore transport of sand in the littoral zone should be evaluated by studying the tidal currents and the climatological data for waves as they occur in the given segment of beach, with a knowledge of how the waves... 

It is conceptually reasonable that the equilibrium area of a tidal inlet is determined by a balance between the transporting capacity of the inlet current and the littoral... 

The most valued part of a coastline is often the sandy beach. Sand is washed into the ocean as the result of weathering of silicon-rich quartz and feldspar rocks upstream and distributed along the shoreline by the action of ocean currents and waves. Human intervention has reduced the amount of sand available. Dams built on streams trap sand as sediment, depriving the ocean of its source of sand. Improper beach management can result in loss of beach sand. The term littoral cell applies to a region of shoreline that includes inflow of sand from a stream or from seacliff erosion, transport of sand generally parallel to the coast by ocean currents and wave action, and eventual loss of sand from the coastal region. 

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