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Natural Processes Figure 4.1 – All shoreline properties are part of a larger
system driven by shoreline features: the landscape, as
Natural coastal processes both maintain and create well as wind, waves, and currents that continuously
our beaches, and they are needed to sustain our move water and beach materials like logs and various
shorelines and their integrity into the future sizes of sediment such as sand, gravel and cobbles.
(Figure 4 .1) . Recognizing that healthy shorelines have natural

variations in the movement of water and sediment is
Erosion & Deposition fundamental to understanding how shorelines work.
Erosion is the process by which sediment is picked While this graphic illustrates one type of transport, it is
up and moved away by currents, waves and wind . important to recognize that transport mechanisms can
vary significantly across shoreline morphologies. The
Powerful and persistent waves and currents can shape of the shoreline will be highly dependent upon
scour away beaches until there is nothing but their interaction with freshwater sources like rivers
rocky substrate left . Deposition, on the other hand, (e.g. deltaic coastlines), as well as the local marine factors
happens when sediment is “dropped off” (deposited) like tidal range, wave energy or currents. The orientation
on the shoreline . Sediment accumulates in certain of the shoreline will also the influence the exposure of
areas where deposition is favourable - often this that shoreline to wave energy and other factors.
occurs around areas of the coastline that stick out . Illustration by: Holly Sullivan
For the same reasons, human-made structures like
seawalls, jetties and groynes can artificially influence
erosion and deposition patterns . Photo by: Mitch Miller

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