River Basins

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River Basins
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Uses

• Rivers provide a source of fresh drinking water,
  a source of food (fishing) and a transport route,
  all of which were very important to the location
  of early settlements.
• Flood plains provide areas of rich, fertile
  alluvial soil. Hence areas like the Canterbury
  plains in New Zealand are intensively farmed.
• Rivers can act as a very effective power source.
  Initially waterwheels were used to power
  factories during the Industrial revolution.
  Latterly the development of hydroelectric power
  has meant a great increase in the building of
  dams to trap the water of a river and its
  drainage basin.

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Uses

• Rivers have always been seen as a convenient way
  of waste removal. This has led to many rivers
  becoming very polluted and in some cases,
  dangerous.
• Estuaries commonly have been used for industry,
  which has been able to build its factories on the
  flat flood plain land. This location is ideal for
  many industries, such as oil refineries, as they
  then have easy access to the sea for transporting
  their goods. The land is flat, cheap and easy to
  reclaim. Usually a local labour source is not too
  far away. The ship building industry used also to
  be found in the estuaries of many of the great
  rivers around Britain, such as the Clyde and the
  Mersey. Now only a few remain.

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Management Of River Basins

• Flooding is the most common thing to have to plan
  around.
• In many cities the flood plain has not really
  been built on.
• Oxford, Exeter and Salisbury are all good
  examples of where this is the case.

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Management Of River Basins

• To prevent the impact of flooding schemes have
  been introduced in many of these places.
• These methods can be very successful, or can
  cause greater problems further downstream.
• In Exeter, flood relief channels and raised
  riverbanks have been used to diminish the flood
  risk.
• The scheme in place is aimed at countering a
  "once in one hundred years" flood, and has been
  severely tested a couple of times.

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Management Of River Basins

• Building dams across rivers can also cause
  problems.
• Obviously there are the advantages of creating a
  large reservoir, which can be used for drinking
  water or as the source of water for a
  hydroelectric power scheme.
• The reservoir will often also be used for
  recreational purposes.
• However the building of a large dam can also
  cause problems by affecting the flow of water
  further down the river, by flooding areas of
  farmland and even towns or villages, and by
  affecting entire ecosystems.

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Management Of River Basins

• The Tucurui Dam in the Northern Brazilian
  rainforest did just this, flooding an area of
  2875 square kilometres.
• It was built to provide power for local
  industries, but at quite a price.
• The lake it created displaced 40,000 people, and
  is estimated to have destroyed hundreds of
  species of animals and plants, some of which may
  never have been actually known about.

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Management Of River Basins

• Rivers are used for the dumping of waste, such as
  sewage, agricultural waste, chemicals and oil.
• All will greatly harm the wildlife of the river
  as well as causing potential problems for humans
  when they drink the water.
• Schemes and by-laws have been introduced to try
  to prevent the pollution of our rivers.