coast of Georgia is constantly changing, with sand and sediment
being moved onto and off of beaches and marshes by wind, currents
and wave action. This so-called sand-sharing system erodes sand
from one point along the coast and redeposits it somewhere else.
The predominant nearshore currents are from north to south, so
usually sand is carried from north to south along the coast.
Island is one of the few places on the East Coast of the U.S.
where the sand-sharing system operates with minimal interference
from human activity. After
a long period of accretion, Nannygoat Beach experienced several
years of erosion during the 1990s, losing 10 meters or more of
dunes. This cycle
of erosion and accretion is constantly active, with sand eroded
from one area of beach by storm waves being deposited in offshore
sandbars and gradually being washed back onto the beach to be
trapped and held by dune vegetation, or being deposited in another
place along the coast. As evidenced by the accretion on the south end of Sapelo during
the past 45 years, some of the sand is transported southward by
the prevailing currents.
beach erosion on Sapelo is only a minor problem even when it does
occur since there are no major structures near the beach.
Erosion of Sapelo beaches can be a more serious problem
that use the beaches as nesting areas and depend on access to
stable beach areas near but above high tide to lay their eggs.
One cause of nesting failure is higher than normal tides
which submerge or wash away birdsí eggs or erode the area where
loggerhead turtles have nested.