Processes Erosion Transport Deposition Abrasion – stones hit bed/bank Attrition – 2 stones in transit hit each other Hydraulic action – action of water on river bed Traction – rolling at high flows Saltation - hopping Suspension – held up Solution – dissolved load Drops sediment where river loses energy e.g. estuary, inside of meander bend Landforms – characteristic features of the Earth’s surface created by rivers and running water. • Upper valley – Rivers and V-shaped valleys with interlocking spurs – created by EROSION • Middle Valley – Floodplains, Meanders and Ox Bow lakes created by a combination of EROSION & DEPOSITION • Lower Valley – Estuaries and mud flats created by the process of deposition
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Processes Erosion Transport Deposition
Abrasion – stones hit bed/bank Attrition – 2 stones in transit hit each other Hydraulic action – action of water on river bed
Traction – rolling at high flows Saltation - hopping Suspension – held up Solution – dissolved load
Drops sediment where river loses energy e.g. estuary, inside of meander bend
Landforms – characteristic features of the Earth’s surface created by rivers and running water.
• Upper valley – Rivers and V-shaped valleys with interlocking spurs – created by EROSION
• Middle Valley – Floodplains, Meanders and Ox Bow lakes created by a combination of EROSION & DEPOSITION
• Lower Valley – Estuaries and mud flats created by the process of deposition
Hydrographs - A graph showing discharge changing over time for a river
Flood management Hard Engineering - building of entirely ARTIFICIAL structures using various materials such as
rock, concrete and steel to reduce or stop the impact of river processes. Soft engineering - managing a river using natural materials and mimicking natural processes to protect more vulnerable areas
Types Dams
Flood walls
Straightening Rivers
Flood plain Zoning
Flood warning systems
Pros Controls flooding/can get HEP from dams/reliable and durable/can last a long time/creates jobs in construction/reduces flood risk
Good for environment/low cost/habitat creation
Cons If they fail can cause catastrophic damage/flooding can be passed on downstream/damages natural environment/not aesthetically pleasing/expensive
Less reliable/less reassuring for homeowners/might not stop flooding
River Tees – example of river landscape and flood management Located in the north east of England. 3 rivers, the River Tees, the River Skerne and the River Leven. The River Tees drains the eastern slopes of Cross Fell (893m, 2000mm+ rainfall per year) in the Pennines and flows eastward to the North Sea. 160 kilometres long. Steep slopes, impermeable rocks and saturated peat in upper catchment. Long history of flooding. The Tees Barrage forms an artificial barrier between the Tees Estuary and the upstream catchment. Approximately 687,000 people live within the catchment area concentrated in the main towns of Darlington, Hartlepool, Middlesbrough, Redcar and Cleveland, and Stockton-On-Tees. There are also large industrial areas such as the ICI chemical works. Flood damage can run into hundreds of thousands of pounds. In total there are almost 8,500 residential properties and over 1,200 commercial properties at risk of flooding. Flood prevention schemes
