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DESCRIPTIONThe River Gade. By Caitlin Ryan. The River Gade. The River Gade is a chalk stream that rises from a spring in the Chiltern Hills. It’s a shallow river. It’s named after the village of Great Gaddesden (where it begins). Chalk Streams and Aquifer. - PowerPoint PPT Presentation
By Caitlin RyanBy Caitlin Ryan
The River Gade
The River Gade is a chalk stream that rises from a spring in the Chiltern Hills.
It’s a shallow river. It’s named after the
village of Great Gaddesden (where it begins).
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.
This process through the chalk allows the water to gather nutrients (useful for plant life) and is cooled by it’s journey through the chalk to emerge at a constant temperature regardless of summer or winter.
Map of River Gade
The River’s Journey
The River Gade travels almost entirely through Hertfordshire.
The river begins it’s 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.
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.
Building The River Gade suffered
problems during the building of Hemel Hempstead’s 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.
Features of the River Gade
Source - Spring at Great Gaddesden Small stream V-shaped Valley - “High Gade Valley” Waterfalls - Rocky ridges in the riverbed
cause little waterfalls.
Floodplain - “Hemel Hempstead” Erosion - Meander about to meet to make an
oxbow lake near Croxley Green
Large floodplain - near Rickmansworth Wide smooth channel
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.
History The River Gade has attracted
people for centuries to live, work and enjoy the countryside in it’s 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.
Quiz? What’s the name of the village where the River Gade
begins? Answer: Great Gaddesden Where does an aquifer collect it’s 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. What’s the name of the rare bird spotted by the River
Gade? Answer: Little Egret