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Beach pollution
There are many ways that beaches can become polluted. The most dangerous pollution is the waste that we pour into the sea each day, and oil spills.
As the waves rise and fall each day, they wash the beach clean – or at least that is what we expect. But although the sea is very good at cleaning the beach, there are times and places where it simply can’t cope.
In fact, for hundreds of years people have supposed that anything they put
in the sea will be carried away. So they have dumped all their waste in the sea and forgotten about it. However, as more people now live by the sea, the amount of waste poured or pumped into the sea has increased greatly.
Pollution that returns to kill
If you look at almost any beach you will
find waste materials – flotsam – washed
up onto it (picture ). Flotsam shows how many of the things we dump into the sea are simply carried back onto the beach by the waves and currents.
E 2 Estuaries and coastal inlets are most at risk because the water is not stirred up much and so does not clean itself very quickly. These are also the places where most people
live. This map shows how disasters can occur. The sewage pipe for
a town leads out to sea,
well clear of the town. Nevertheless, the waves and currents simply drive the
sewage back to the town’s beach and into the estuary.
In many parts of the world, coastal towns and cities pour their sewage through pipes directly into the sea (picture 2). But, as we have seen earlier in this book, waves can push water back onto the beach, so it
is possible for all the sewage to be washed back up on the beach. The difference is that,
G  Typical flotsam on the beach. What you can see may be dangerous. But the water may also contains dangerous germs you can’t see.
Waves carry sewage back to shore.
Sewage gets back into the estuary on rising tide.
Sewage pipe
Sewage enters sea from a long pipe.
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