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Photos by: Mitch Miller

Beach Starvation
Areas with hard armour will often experience
a shift in substrate type — if it’s sandy, it may Photo by: Isobel Pearsall
become more gravel-dominant, since sediment
may no longer be nourishing the area . The
nearshore sediment budget describes whether a
shoreline has a surplus or deficit of sediment, and
this tells us whether the beach will be eroding or
accreting . We would say that a beach is starved
if it has been cut off from its source of sediment .
Hard armouring structures can leave beaches
starved of sediment . Deposition and erosion occur
in harmony at the shoreline, but when structures BEACH NOURISHMENT:
like groynes are installed, beaches are cut off from The addition of sediment to a
their supply of sediment and the dominant process shoreline to build up the profile of
becomes erosion . This might look like a beach
with large cobbles, but this was once actually a the beach and replace sediment
mixed-sediment beach, and now the soft sand that had been lost due to longshore
has been eroded away .
drift or other erosive processes.
Throughout British Columbia, residential clearing Beach nourishment is a technique
and shoreline armouring, coupled with the
impacts of sea level rise, affect the sustainability to maintain or restore a sediment
of nearshore processes and threaten high value beach in a particular area (often
habitat, including areas where forage fish spawn .
for tourism purposes,) but can be
a part of a nature-based approach

to shoreline restoration to improve
the functioning of the habitat as

well. This approach is less costly
than hard armour and may require
Photo by: Isobel Pearsall
maintenance over time. Sometimes

beach nourishment is necessary
when natural sediment transport

processes have been impeded by
armouring structures.

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