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Environment and development
in coastal regions and in small islands
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Wise practices for coping with beach erosion: Anguilla

Department of Fisheries and Marine Resources, Anguilla
Department of Physical Planning, Anguilla
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 Anguilla’s shores. Tourism is a driving force in Anguilla’s economy so the state of its beaches is of major importance.

Natural forces  

  • Hurricanes and tropical storms, occurring between June and November, cause dramatic beach changes usually resulting in serious beach erosion.
  • High waves in winter resulting from storms in the North Atlantic Ocean, and known as swell waves, or locally as ‘groundseas’.
  • Sea-level rise, which is a long-term factor, taking place very slowly over decades causes shorelines to retreat inland.  

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  

  • Removing sand from beaches and dunes for construction purposes causes erosion and the loss of beaches and coastal lands, destroying the natural heritage of the coast and reducing the vibrancy of the tourism industry.
  • Building too close to the beach interferes with the natural sand movement and may impede beach recovery after a serious storm or hurricane.
  • Badly planned sea defences may cause the loss of the beach, and of neighbouring beaches.
  • Pollution from human activities on the land may damage coral reefs and seagrass beds; these biological systems protect, and provide sand to the beaches.
  • Removing vegetation from the dunes destabilises these protective sand barriers; and clearing sites inland results in increased soil and dirt particles being washed offshore and smothering coral reef systems.
It was unwise to 
rebuild a beach 
bar at Sandy 
Island in October
1995 immediately
after Hurricane 
Luis, as waves 
reshaped the cay
leaving the 
structure in the sea
 

***********

WHATS HAPPENING WITH ANGUILLAS BEACHES?


Shoal Bay in 1992  
In order to manage these changes, Anguilla’s beaches have been monitored since 1992 by the Department of Fisheries and Marine Resources, who measure the beach slope and width every 3 months at numerous sites around the island, as well as at the offshore cays.  

Beach monitoring 
in progress at 
Shoal Bay West,  1992

Location of monitored beaches

 

***********

SAND IN, SAND OUT

When Hurricane Luis struck in 1995, much of the beach was lost at Mead’s Bay on the north coast. In the months and years after the hurricane the beach recovered, but not to the pre-hurricane level.  

BEACH PROFILE
Mead’s Bay Central. Beach erosion

  
Beachfront properties 
were transformed 
overnight after 
Hurricane Luis struck 
in 1995. Mead’s Bay 
Central: reference 
point before and after 
Hurricane Luis
 

***********

DUNES AS RESERVOIRS OF SAND

Dunes function as reservoirs of sand, supplying beaches during storms and protecting coastal land from flooding.

BEACH PROFILE
Cove Bay Central. Beach erosion

   
At Cove Bay there used to be an extensive line of sand dunes separating the salt pond from the sea and measuring more than 3 metres high. In 1995 Hurricane Luis eroded the seaward face of these dunes and in 1999 the waves generated by Hurricane Lenny broke through the dunes in places, joining the salt pond to the sea.  


Cove Bay, 2 months after Hurricane Lenny struck 
(Nov. 1999). There used to be a wide belt of sand 
dunes separating the salt pond (right side of photo) 
from the sea. Now only eroded remnants exist


Sandy Ground.
During Hurricane 
Lenny (Nov. 
1999) the sea 
and the pond 
were temporarily 
joined

***********

WISE PRACTICES FOR A HEALTHY BEACH


Seagrape trees  


Building sand fences at 
Savannah Bay, 1997

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 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:

  • Planning new development so that it is a ‘safe’ distance behind the beach will reduce the need for expensive sea defence measures in the future.
  • Revegetating dunes with native vegetation e.g. grasses and vines, and planting beach areas beyond the reach of storm waves with salt-resistant, deep-rooting trees, such as sea-grape. (Additional development controls are required in the fragile offshore cays.)  
Recommended coastal development setback distances in Anguilla  
l
l

(18m (60ft) FROM VEGETATION LINE  
30m (100ft) FROM VEGETATION LINE  

l
l
45m (150ft) FROM VEGETATION LINE
92m (300ft) FROM VEGETATION LINE
   

Sand fences and sea lavender, Shoal Bay, 1998  


Planting dunes 
with native 
grasses, 
Maunday’s Bay, 
1996


A retaining 
wall under
construction at
Mead’s Bay 
after Hurricane
Luis, 1995

  • Resorting to ‘hard’ engineering structures such as seawalls, revetments and bulkheads, only when there is a need to protect beachfront property from wave action. Such structures, even with careful design, result in the loss or narrowing of the beach over time.
  • Considering all other beach enhancement measures such as offshore breakwaters, groynes and beach nourishment (placing sand from the offshore zone or from an inland source on the beach) at a particular site. All such measures require careful design and environmental impact assessments, so always first consult the Department of Physical Planning.  


Moving sand from an accreting part of Shoal Bay West to an eroded part, 2000

Planners and a developer discuss a recently 
constructed seawall at Mead’s Bay, Anguilla, 1998

***********

HERE TODAY, GONE TOMORROW

The table shows generalised rates of change at the measured beaches in Anguilla. During the 1990s, all of the beaches, with one exception, showed erosion, a result, at least in part, of the impact of several severe hurricanes since 1995. However, most beaches in Anguilla show erosion along one part of the beach and accretion (or build-up) at adjacent sections, thus these figures must be treated as average trends.

Beach change rates in Anguilla (metres per year)

A negative rate of change () indicates erosion and retreat of the shoreline, a positive rate of
change (
) indicates accretion or advancement of the shoreline towards the sea


Maunday’s Bay after Hurricane Lenny in 1999. 
Hotel villas were undermined and stairways leading 
over the once extensive dunes were left as isolated 
monuments

Measuring 
sand loss after 
Hurricane Luis,
1995  

***********

WISE PRACTICES CHECKLIST
Plan for existing and future coastline change by positioning all new development (large and small) a ‘safe’ distance landward of the vegetation line (consult the Department of Physical Planning for information on ‘safe’ distances).  
Ensure the physical planning process is fair, equitable and transparent.  
Involve all stakeholders (e.g. government agencies, coastal communities, non-governmental agencies, coastal residents, beach users and others) in the review and permitting process for major developments.  
Review and carefully consider ALL options when considering ways to slow down the rate of coastline change, these should include planning, ecological and engineering measures.
Continue to monitor the rate of coastline change and share the findings with all other stakeholders.
Respect the rights of all beach users.
Involve Anguilla’s youth in the management and conservation of beach resources.
Provide for public access to all beaches, and where appropriate provide facilities for beach users (e.g. parking, safety measures, sanitary facilities).
Conserve and restore vegetative cover, both adjacent to the beach in order to stabilise the sand, and further inland to reduce sediment reaching the reefs and sea grass beds.

For more information on shoreline 
change in
ANGUILLA consult:

Department of Physical Planning
The Valley, Anguilla
T: (264) 497 5392; F: (264) 497 5924
W: www.gov.ai/planning

Department of Fisheries and Marine
Resources, Crocus Bay, Anguilla
T: (264) 497 2871; F: (264) 497 8567

E: dfmr@anguillanet.com

For more information on shoreline 
change in the
CARIBBEAN consult:

Coping with Beach Erosion
by Gillian Cambers
UNESCO Publishing, 1998
ISBN 93-3-103561-4

This booklet is a result of co-operation  
between UNESCO, the Caribbean  
Development Bank and Anguilla’s  
Government agencies  

Illustrations: Barbara Navi – Photographs: Gillian Cambers – Design: Eric Loddé

__________________

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