|Environment and development
in coastal regions and in small islands
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WALLS ON THE SEAFRONT
St. Barths, well-known for her fifteen stunning beaches,
has recently seen several of them being altered, either by
shrinking or by simply disappearing on a length of a few meters ,
and beachfront properties becoming beachless properties. In St.
Jean, the two fringes of sand have had portions of their
coastline protected by a wall that is attacked by furious waves.
Should the tourist brochures soon change the number of beaches in St. Barths?
The experiences of nearby islands are interesting. Dr Gillian Chambers is the coordinator of COSALC (Coast and Beach Stability in the Caribbean Islands), a program of UNESCO, co-sponsored by the University of Puerto-Rico Sea Grant Program.
Forty years ago, tourism's economic potential had not yet shaped the Caribbean's development policies. During the 1960's, our islands' lush, green-fringed beaches were seen as a poor risk for permanent structures. Islanders, looking toward local resources for subsistence as well as commercial and social growth, found beachfront land to be poor for agricultural production, plagued by mosquitos from nearby wetlands and highly vulnerable to a vast and unpredictable sea. It was only common sense to respect so changeable an environment, and build - with the future in mind - way back!
Tourism has changed our outlook, to say the least. Just as we have looked to outsiders as a source of employment, we have adopted a tourism-based lens with which to consider the surrounding geography. And in the past forty years, a majority of the Caribbean people have looked - and gravitated - toward the shore as a source of economic and social activity.
Sea Walls Serve a Few
While our coastlines were undeveloped, beach erosion happened but it went largely unnoticed. Now however, coastal development is threatened by the normal erosion process, plus what seems to be a rise in sea level throughout the region, in addition to storm-related surges of ocean water that can easily destroy million dollar buildings within a few hours time. As a result, more and more oceanfront property owners have built structures such as sea walls in order to protect luxury hotels and private homes.
But these hotels, homes and other buildings are being built on land that can easily wash away. And while sea walls may protect small beachfront areas, they often lead to accelerated beach erosion by preventing the natural process of inland sand migration. Concrete sea walls also conribute to the "armoring" of once-green coastlines. This esthetic defilement surely lowers the tourism value of our shores.
Alternatives to Concrete Armor
Most of the beaches of the small Caribbean islands are eroding. The results of beach monitoring projects maintained since 1988 show that a full 2/3 of our beaches are eroding, and only 1/3 are stable or accreting. Comparison of aerial photographs shows that the erosion trend goes back over the past 30 years.
The Pacific islands are struggling with similar erosion problems. For instance, on the Hawaian island of Maui, 62% of the sandy shoreline is eroding. Walls and revetments have been built to protect beachfront properties, but in front of these sea walls, the beaches have narrowed most dramatically.In response, various state agencies have joined together to adopt an interim policy of prohibiting the construction of sea walls or revetments, while the options for beach conservation are being considered. For now, beachfront property owners are limited to the use of large, geotextile sandbags to protect their land from wave action. Of course, the sandbags are only a temporary measure.
Closer to home, each of the eastern Caribbean islands will probably be impacted by a major hurricane during the next thirty years. Beach and shoreline erosion will inevitably impact existing beachfront properties within the same time span. Rather than wait until the government mandates restrictive policies such as those adopted in Maui, we should begin to plan and take action now.
Planning for Coastline Change
Since 1997, a project titled "Planning for Coastline Change" is helping the smaller Caribbean islands to plan for the future by establishing safe setbacks between new developments and the active beach zone.
Planning for Coastline Change had its beginnings in catastrophe. In 1995, Hurricane Luis swept a path of destruction from Antigua to Anguilla and reaching out to islands as far away as St. Lucia and Puerto Tico. After surveying the damage, Anguilla sought to put in place planning mechanisms to avoid future hurricane damage to coastal infrastructure.
As a result, a generic method was fine tuned and made easy to use as the following addition of these parameters:
Modified by the impact of other factors, geological or social, specific to the place.
All such setbacks are measured from the line of permanent vegetation, and no longer the high watermark, as it was used in the past, that changes from day to day!
The Atlantic walls
The prudent use of coastal development setbacks will ensure the safety of future buildings and help to protect our beaches. But what can we do about existing structures?
1. Act before the situation becomes a crisis. Once the water scours the foundation of beachfront property, there is little one can do but place boulders or sheet piling into the sea in order to lessen the waves' impact.
2. Many beaches in the eastern Caribbean are what we call bay head beaches, extending for less than two mileslong and contained by cliffs or low rock headlands. Beach front property owners and other people interested in the fate of a particular beach, including beach users, fishermen and other community members, should meet to discuss existing and potential problems, and how to avoid and/or solve them collectively. Remember: the actions of each individual will affect the entire beach.
3. Investigate possible solutions! Consult local government agencies, which may be able to advise, or suggest an expert in the field of beach erosion and conservation.
Adapted solutions to existing developments
The best solutions always depend upon the specific beach - and island - involved. However, most islands would benefit greatly if authorities stopped issuing licenses for sand mining on our beaches. Other low cost solutions may include planting deep rooting trees such as manchineel, sea grape and almonds, and the restoration of sand dunes.
Alternatively, if sand moves to one end of the beach and accumulates there, the frequent distribution of sand along the beach may be an option. Other more costly options include beach nourishment and the construction of coastal structures such as breakwaters and groins.
No one solution will be appropriate for all beach erosion problems when development is already there.
Will we keep our beaches for as long as possible for the benefit of all residents and our visitors, or will we succumb to the pressure to sacrifice the common good for the short-term benefit of an economically powerful minority. The choice is up to the islanders.
From Nicole Aussedat, based on Dr. Gillian Chambers' work, pages 10-11 in St-Barth Magazine 165, 8 March 1999