WJEC GCSE Geography A Unit 1 The Core

WJEC GCSE Geography A Unit 1 – The Core A- The Physical World Theme 1 Water

Theme 1 Water n n n n What are river processes and what landforms do they create? 1. 1 What processes are associated with rivers? 1. 2 What landforms result from these processes? 1. 3 How do these landforms and processes affect the lives of people living along rivers? How should rivers be managed? 2. 1 How successful are different management approaches to the problems of flooding? 2. 2 Should we change our approach to river and floodplain management in the future?

Theme 1 Water 2. How should rivers be managed?

2. 1 How successful are different management approaches to the problems of flooding? n n Flooding is seen as something that can be and needs to be managed by people. There are many different approaches to the management of rivers. Two important ways of managing rivers are through HARD and SOFT ENGINEERING. The river channel and / or the whole river basin can be managed. A flood warning system can also be in place.

Hard and soft engineering n n Hard engineering is using man made structures (e. g. a dam) to control rivers. Soft engineering is using natural practices to reduce erosion and achieve stabilisation (e. g. using vegetation). This means working with river processes and preserving habitats. Sometimes the best approach is a combination of hard and soft engineering methods. Soft engineering methods are becoming more and more widely used due to environmental protection becoming more important.

Examples of hard engineering Dams and reservoirs; n Channelisation (straightening and dredging); n Flood walls; n Levees; n Artificial channels. n

Examples of soft engineering Setting flood banks further back; n Constructing flood relief channels but keeping original channel in natural form; n Restricting of development on floodplain (e. g. parks, sports fields and nature reserves not housing and industry). n

Use of floodplain to hold a carnival Agricultural use of floodplain

River channel management n n Ø Ø Ø Very few river channels are entirely natural. People can interfere with a river channel directly and indirectly by: Building dams; Straightening river channels; Dredging channels (dredging = cleaning out the bed of a river); Cutting down vegetation on the banks; Abstracting (removing) water.

River restoration n n The quality of rivers and surrounding land is degrading due to: Ø River channels being straightened and deepened; Ø Floodplains being built upon and farmed intensively. River restoration means reversing this process. It aims to return a river and surrounding land to its natural state i. e. being allowed to meander and flood. It is an example of sustainable management. Such projects are usually locally based and involve the local community.

River restoration The River Restoration Centre has a case study of a local river where soft engineering has been used to restore the river to a more natural course. n This river is the Afon Ogwen in Nant Ffrancon. Task Go to: http: //www. therrc. co. uk/projects/rrc_ogwen. php to find out more about this project. Report back to the class what you have found. n

River basin management n n n The Environment agency is responsible for the management of river basins in England Wales. Important aspects of their work are water resource management, flood defence and pollution control. A problem with river basins is that rivers often flow through different planning regions and different countries. Sometimes a watershed approach is taken when these regions and/or countries work together to manage the whole river basin.

The UK’s Flood Warning System There are four levels of flood warning issued by the Environment Agency: • Flood watch • Flood warning • Severe flood warning • All clear

Some existing flood warning methods Door knocking; n Flood wardens; n Mobile loudhailers; n Flood sirens; n Flashing signs; n TV and radio broadcasts + teletext; n Telephone (Floodline) n

Some new flood warning methods Mobile telephone SMS text messaging and voice mail; n E-mail; n Digital TV and radio broadcast; n Internet (data, photographs and warnings) n Home alert systems. n