Caribbean beaches - The sands of time are running out

by Nancy McGuire

The sandy beaches of the Eastern Caribbean have always been regarded as a free and limitless resource. Not any more. Governments, reports Gemini News Service, are realising that sand-mining is a major cause of erosion.

Caribbean beaches still deliver the sun and sea promised in the tourist brochures, but they can no longer always boast of endless sand. Beaches are being eroded by natural processes and human activities. The phenomenon has been ignored by governments-falsely confident of a resource that would never run out - but now severe damage has occurred, politically unpopular decisions are required and huge costs look likely.

A decade ago, Telescope Point on Grenada's east coast was a beautiful beach. It has been virtually destroyed. Heavy sand mining, indiscriminate removal of mangroves, strong north-east trade winds and a jetty expansion which damaged the reef have done the job. What remains is uprooted coconut trees, mud and a narrow strip of sand. Monitoring shows that the beach is eroding by between three and four metres a year.

Destruction of the beach has disrupted the habitat of snails. crabs and other creatures, and scientists warn that this will have a long-term effect on the marine food chain. Telescope was once a nesting ground for leatherback turtles. The largest of the turtle family and now an endangered species, leatherbacks used to return to the place of their birth to nest in the sand. They no longer do so.

About 85% of sand for use in Grenada's construction industry is taken from the island's beaches. There is no monitoring, and regulations controlling which beaches are open for mining are often ignored by residents and the authorities.

Concrete is preferred to wood all over the region because of its resistance to weather and termites. Traditionally, private citizens have regarded beach sand as freely available for house construction, but in terms of quantity, governments have often been the biggest culprits in removing sand for public works projects and filtration systems.

Counter-measures are not always appropriate. Valerie Isaac of the natural resources management unit of the Organisation of Eastern Caribbean States (OECS) recalls a workshop in St Vincent at which the government's director of planning indicated that all beaches would be closed to sand mining. The result, she says, 'was a rush on the beaches-people were stockpiling like crazy.'

Tackling the problem

St Vincent has now constructed facilities to handle imported sand from Guyana, Dominica and other places. Local sand is taken from a river and also made from pumice, a light volcanic rock. Such attempts to tackle the problem are part of a response to recommendations by COSALC (Coast and Beach Stability in the Lesser Antilles) working with the OECS. COSALC was founded by UNESCO in 1985 after erosion in the Eastern Caribbean had become visibly more serious. It has drawn up recommendations for coastal zone regulations, which several countries have found helpful. The British Virgin Islands used the regulations to introduce mangrove management, as the extensive mangrove root systems play an important part in marine life and in the sustainability of beaches and rivers.

Most sand in the British Virgins is obtained from offshore dredging. Some countries have been slower in finding alternatives. The OECS estimates that regionally, 16% of sand consumed is imported, and 20% is taken from local beaches. Restricting removal of beach sand is unpopular because alternatives such as crushed stone from quarries cost money. But in 1992, Montserrat introduced stringent regulations, closing all beaches to sand mining.

Beaches are continually monitored, and barriers control vehicle access. Construction with quarry sand required remedial work on some new buildings but the government has kept all but one beach closed to sand mining, and gives training on efficient ways of using quarry sand and avoiding siltation.

In St Lucia, sand for government projects is imported from Trinidad and even from Canada. Sand dredged from offshore is also used, and river mouths are open at certain times of year to local villagers. Pumice is extracted from private mines and crushed.

Other causes

Beach mining is not the only culprit. Other human causes of erosion include construction of port facilities that interfere with the movement of water, and pollution. Tropical storms and the endless pounding waves have brought about significant long-term changes to the coastlines of the Lesser Antilles. Sea defences are expensive and can create new forms of erosion.

Eastern Caribbean governments are gradually realising that halting erosion and rebuilding beaches are complicated and costly challenges. Dr Gillian Cambers, COSALC's programme coordinator based at the University of Puerto Rico, who has studied beaches for several years, told participants at a recent workshop in Grenada that when sewage controls are inadequate, algae competes with coral reefs for light, and ultimately grow over the corals. 'If the reef is under stress from pollution such as excessive siltation,' she said, 'the complex reef ecosystem will be less healthy and produce less sand. In turn, the beach will suffer because the supply of sediment is reduced or cut off.' She stressed that many factors contribute to the disappearance of beaches in the Eastern Caribbean. 'It is not always just waves. It's not necessarily sand mining. It's not necessarily only sea-level rise. We also have to look at other factors such as pollution. It's like anything to do with the environment: there's no simple cause and effect. Its causes and effects', she emphasised.