By Caitlin Ryan

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The River Gade

• By Caitlin Ryan

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The River Gade

• The River Gade is a chalk stream that rises from
  a spring in the Chiltern Hills.
• Its a shallow river.
• Its named after the village of Great Gaddesden
  (where it begins).

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Chalk Streams and Aquifer

• The River Gade is a chalk stream with very clear
  water. Chalk streams are globally rare, which
  makes the River Gade even more special.
• Chalk streams are fed from groundwater. This
  water is stored in an aquifer.
• An aquifer contains layers of chalk that soak up
  rainwater like a sponge. At various points the
  water emerges as springs, which feed the streams.

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Aquifer process

• This process through the chalk allows the water
  to gather nutrients (useful for plant life) and
  is cooled by its journey through the chalk to
  emerge at a constant temperature regardless of
  summer or winter.

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Map of River Gade
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The Rivers Journey

• The River Gade travels almost entirely through
  Hertfordshire.
• The river begins its journey from the springs in
  Great Gaddesden.
• It travels through Hemel Hempstead, Kings Langley
  and Croxley Green to Rickmansworth.
• Finally it joins the River Colne and The Grand
  Union Canal.
• Later joining the River Thames.

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Pressures on the River

• In the past couple of years many chalk streams
  have been on the verge of extinction due to a
  lack of rain. Thankfully the recent wet weather
  has saved chalk streams.

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Building

• The River Gade suffered problems during the
  building of Hemel Hempsteads new town after
  World War 2.
• The demand for water increased.
• High levels of water were drawn.
• The natural water table level dropped causing a
  drop in the river depth.

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Features of the River Gade
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Upper Course

• Source - Spring at Great Gaddesden
• Small stream
• V-shaped Valley - High Gade Valley
• Waterfalls - Rocky ridges in the riverbed cause
  little waterfalls.

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Middle Course

• Floodplain - Hemel Hempstead
• Erosion - Meander about to meet to make an oxbow
  lake near Croxley Green

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Lower course

• Large floodplain - near Rickmansworth
• Wide smooth channel

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Wildlife

• The River Gade is very important to wildlife.
  Including many species that are rare and come
  from different countries. A little egret was seen
  here on one especially bleak winter.
• The meadows support a diverse community of birds.
  Such as finches, thrushes, waders and a wildfowl
  during winter and other birds breed on the
  meadows in the summer.

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History

• The River Gade has attracted people for centuries
  to live, work and enjoy the countryside in its
  beautiful valley.
• The Romans created a settlement in the area now
  occupied by Gadebridge Park.
• The River provided a source of power for a corn
  mill at Water End.
• Watercress used to be grown for the London
  market. Traces of the old watercress beds can
  still be seen from Google Earth.

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Quiz?

• Whats the name of the village where the River
  Gade begins?
• Answer Great Gaddesden
• Where does an aquifer collect its water from?
• Answer The Rain
• Name all four of the towns and villages the River
  Gade travels through?
• Answer Kings Langley, Hemel Hempstead, Croxley
  Green and Rickmansworth.
• Whats the name of the rare bird spotted by the
  River Gade?
• Answer Little Egret