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- River meetings
This is the point on the river where both arms meet (a confluence),
and the river is back at 'full strength.' The river is now entering
an industrial area where there is the potential for pollution, but
first it passes the Broad Oak Lakes Nature Reserve. The river also
has totally natural banks with vegetation cover, creating suitable
habitats for birds and mammals.
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- Broad Oak Lakes
Broad Oak lakes were created around 70 years ago by the extraction
of gravel from the ground. They are now a small wetland nature reserve
and is managed by the Canterbury (Broad Oak) Environmental Education
Centre.
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- Flooding
As the banks are natural and the channel not as efficient as upstream,
the water flows more slowly. This causes the level to rise, often
flooding into the lakes, causing problems such as flooding of the
centre buildings.
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- Fish starved of oxygen
When the river drops sediment into the lakes, the nutrient level increases,
this is food for algae and a small water surface plant called duckweed
(see photo). These then grow and can cover the whole lake surface
during the summer. This can reduce the level of oxygen in the water
and starve the fish of oxygen. This over supply of nutrients is called
eutrophication.
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End of the Virtual
Tour
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