Environment and development in coastal regions and in small islands |
alternative PDF version
Wise practices for coping with beach erosion:
Nevis
Nevis
Historical and Conservation Society
Department of Physical Planning, Natural Resources and Environment, Fisheries
Division
University of Puerto
Rico, Sea Grant College Program
Caribbean Development Bank
UNESCO Environment and Development in Coastal Regions and in Small Islands
FORCES
TO BE RECKONED WITH
Beaches
are continuously changing – from day to day, month to month and year to year
– as the natural forces of wind and water meet the land. These changes, which
have been taking place for millions of years, are linked to variations in wind,
waves, currents and sea level height.
But
it is not just natural forces that change the beach, humans have a big role to
play in this process as well, through mining stones and sand from the beaches
and dunes, polluting and damaging coral reefs, and constructing buildings and
walls too close to the sea.
Changes
in the beaches affect everyone. The coast is a place we are all attracted to for
recreation, sports and simple enjoyment. This constantly changing and
hazard-prone coastal environment is also where the greatest financial investment
is concentrated, as large tourism properties and establishments continue to be
attracted towards the shores of St Kitts and Nevis. Tourism is a driving force in
country’s economy so the state of its beaches is of major importance.
Natural
forces
Since
1995, the Atlantic Basin (including the Atlantic Ocean, the Caribbean Sea, and
the Gulf of Mexico) has entered a more active hurricane cycle, which may
continue for more than 20 years. |
Hurricane frequency between 1990 and 1999 in the Atlantic Basin |
Source: Gray et al. http://typhoon.atmos.colostate.edu/forecasts/1999/nov99/ |
In
the Atlantic Basin the number of really severe hurricanes (categories 3, 4 and
5) increased from one per year (1990 –1994) to four per year (1995 – 1999).
Human forces |
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WHAT’S
HAPPENING WITH NEVIS’
BEACHES?
In
order to manage these changes, Nevis’ beaches have been monitored since 1988 by the
Nevis Historical and Conservation Society, who measure the beach slope
and width every three months at numerous sites around the island.. |
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Beach
monitoring |
Location
of monitored beaches
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SAND
IN,
SAND OUT
When Hurricane Hugo struck in 1989, much of the beach was lost at Pinney’s Beach on the west coast. In the months and years after the hurricane the beach recovered, but not to pre-hurricane levels. The beach was further eroded by successive hurricanes: Hurricane Luis in 1995, Hurricane Georges in 1998 and Hurricane Lenny in 1999.
BEACH
PROFILE |
Pinney’s
Beach,
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Pinney’s
Beach, October 1995, after Hurricane Luis |
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DUNES AS RESERVOIRS OF SAND
Dunes function as reservoirs of sand, available for
supply to the beach during storms. In addition, they protect coastal land from
flooding.
BEACH
PROFILE
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At Indian Castle, there used to be extensive sand dunes, several metres high. These were mined extensively for construction sand in the 1970s and 1980s, and the remnant dunes were eroded by the recent hurricanes. |
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Extensive
mining in the ‘70s and |
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Low sand
dunes, stabilised with vegetation, as seen at White Bay, play an important role in maintaining the beach, 1996 |
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This
restaurant at |
WISE
PRACTICES FOR A HEALTHY BEACH |
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The
state of the beach affects everyone’s lives. There are no simple or universal
solutions to shoreline erosion, since there are often several factors, both
human and natural, contributing to the problem at a particular beach. Each beach
behaves differently, so it is advisable to find out as much information as
possible about a particular beach before taking any corrective action. It is
necessary to consult the Department of Physical Planning, Natural Resources and
Environment before undertaking any
action at a beach. Some
forces of change, such as hurricanes and winter swells are natural, and there is
little we can do to stop them, yet there are ways we can help to slow down the
rate of erosion:
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Recommended coastal development setback distances in Nevis | |||
l l |
18m
(60ft) FROM VEGETATION LINE |
l l |
37m
(120ft) FROM VEGETATION LINE 152m (500ft) FROM VEGETATION LINE |
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After Hurricane
Lenny, sand |
Planning officials inspecting a newly constructed rock revetment at Pinney’s Cotton Ground, 1999
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Groynes
built along the |
...but not
in others |
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In 1981, there was a small beach at Cherlestown By 2000, the
beach had disappeared and land has been |
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HERE
TODAY,
GONE TOMORROW
The table below shows generalised rates of change at the measured beaches in Nevis. During the decade of the 1990s most of the beaches showed erosion; a result, at least in part, of the impact of several severe hurricanes since 1989. The erosion was especially severe on the west coast beaches.
Beach change rates in Nevis (metres per year) |
A
negative rate of change (–) indicates erosion and retreat of the shoreline, a
positive rate of |
Damaged beach bar at
Golden Rock, Pinney’s |
damage at Pinney’s Beach after Hurricane Luis, 1995. The fallen tree and piles of washed-up seagrass point to the damage caused by the hurricane waves |
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For
more information on shoreline Nevis
Historical and Conservation Society Department of Physical Planning, |
For
more information on shoreline Coping
with Beach Erosion
This
booklet is a result of |
Illustrations: Barbara Navi – Photographs: Gillian Cambers – Design: Eric Loddé