• The importance of river systems

Unfortunately, the rapid increase in the number of people living near the coast this century has created an imbalance that is destroying the very resources that made these places
attractive. Dredging of estuaries, dams and irrigation systems (including on rivers such as the Nile, Danube, Mississippi, Ganges and Colorado) can deprive coastal areas of the silt
and sediment that are needed to replace natural erosion and can destroy fisheries or block migration. Florida's famous Miami Beach has already needed a US$80 million rescue plan.
The Franklin Dam on the Ganges has reduced water flow by 75 percent in Bangladesh, turning fertile farmland to desert and destroying mangrove forest, with a loss to the state
estimated at US$4 billion. World-wide since 1950, some 30,000 dams have been built (over half of them in China), diverting or damming 13 percent of global river flow to the sea.

At the opposite extreme, deforestation upriver causes a massive build up of soil in estuaries and has blocked more than one port, with expensive dredging adding to the cost of lost
trade revenue. Meanwhile, untreated sewage pumped into the sea makes the water unfit for bathing and encourages the growth of algae that deprive the water of oxygen, killing fish
and other marine life.

    • Need for coordination

Too often, there is no co-ordination between the various actors in coastal development - fisheries, entrepreneurs and developers, water authorities, local government, housing
authorities, waste disposal, etc. And goals are often short-term, either for quick profit or to win votes in elections. According to a recent UNEP report on the Status of the
Environment, 1/3 coastal regions run a high risk of degradation, especially from infrastructure development and pollution. In 4/7 coastal regions the degradation is increasing.

The United Nations Conference on Environment and Development (UNCED), held in Rio de Janeiro in 1992, called for an integrated approach to management of coastal areas, to
allow development that preserves the resources for future generations. UNESCO's Environment and Development in Coastal Regions and in Small Islands initiative, created in 1996,
is one response to this.

    • International legislation

For centuries, territorial limits extended just three nautical miles - the distance of the horizon, as seen from land. But expanded shipping capabilities, radar and satellite imagery and
intense competition for dwindling resources have rendered this frontier meaningless. Territorial limits were extended to 12 nautical miles, while the 1982 United Nations Convention
on the Law of the Sea (UNCLOS) created Exclusive Economic Zones (EEZ) extending 200 nautical miles out from the coast.

This Convention, which came into force in November 1994, (although some signatories have yet to ratify it), has, according to Federico Mayor, "opened a new era in the history of
the relations of man and the sea". This legislation will have a major impact on coastal and island nations, since over 90 percent of the world's natural and living resources are in the
continental shelf area. UNCLOS also significantly increases the territory of coastal nations. The EEZ principle, for example, gives Australia some 11 million square kilometres of
coastal waters - and with a mostly barren interior, 80 percent of Australia's population lives on the fringe of this zone.

Information courtesy of UNESCO: