Flashcards in The ribble drainage basin Deck (15)
Where is it?
It is in Lancashire UK.
How long is the river and what is the size of the drainage basin?
The river is 110 km long and drains a basin of 2183 km squared.
What is the rivers course?
The drainage basin has a source in the central Pennines, it then flows southwards and then westwards before joining the Irish Sea at Preston.
What major estuaries does it contain?
It contains several major estuaries including the Hodder, The Darewn, The Douglas and the Calder.
Where does the upper course of the river drain?
The Upper course of the Ribble and its tributaries drain areas of Millstone Grit and Carboniferous limestone.
What type of rock does the river flow over?
The Millstone Grit is formed of densely packed sand particles with very few pore spaces. Overland flow is rapid as the rock is impermeable.
The upper course contains large areas of peat soils.
How does the type of rock change the water flow?
Overland flow is rapid as the rock is impermeable.
Through flow reaches the river channel quickly.
Most areas are covered with glacial drift. As this is largely unconsolidated, with few large pore spaces, overland flow is fast.
Describe the drainage basin.
The basin is also one of the largest in the northwest of England.
‘There are extensive flood plains in the upper river, formed before the river was rejuvenated as a result of isotactic sea-level fall.’
How does rainfall vary?
Rainfall varies from 1775 mm at the river’s source to 890 mm at the estuary.
The rainfall is evenly distributed throughout the year.
When does overland flow often happen?
Infiltration-excess overland flow is most common after intense summer thunderstorms. Saturation excess overland flow is more common in late winter, although the peat can store large quantities of water.
Give an example of where urbanisation affects water flow?
A major tributary, the River Calder, flows through heavily urbanised areas such as Burnley.
Discharge is rapid because water is directed into the river by storm drains and runoff from concrete and tar surfaces.
What recreational activities take place?
Recreational activities include conservation areas, fishing and footpaths.
Give an example of a conflict.
Conflicts are caused by canoeing desiring non-polluted water and industry, and conflict between spaces and how much of it should be taken up by activities.
Give some examples of industry.
Water is abstracted for industrial uses.
The river is mainly used to dispose of sewage, and sewage treatment works are needed.