Components of irrigation system

give you the information about the components of irrigation system.why Dam, barrage, head works, canal, major canal ,minor canal, water courses and field channels are made and how these works, all these are discussed in this

1. Components of irrigation system

2. Water Shed Water shed is an area which receives precipitation/rainfall and contributes to the formation of natural flow leading to the development of rivers Rate of runoff depends on the vegetations , land topography , degree and length of slope shape and infiltration characteristics of the water shed Appropriate management of watershed can plays an important role in controlling sediments inflow into the irrigation system

3. Rivers A river is a natural stream which develops as a result of runoff produce by the watershed It receives water from watershed and conveys to downstream system components through dams and barrages Indus , Jhelum and Chenab are the some of the examples

4. Dams A dam is a control structure built across a river Functions of Dam Storage of water for regulating the flow regimes Originate irrigation canals to facilitates water supplies to irrigation land Raise the head of water for operating irrigation canals Hydropower generation to provide electricity for domestic and industrial use Major dams include T erbela and Mangla though also serves as water storage resevoir

5. Barrages A barrage is also a control structure which is built across the river mainly to raise the level of water and create a limited temporary storage for facilitating canal operation A Barrage diverts river water to the canal through gate operation The examples include Trimu , Rohri and Sukkur barrages

6. Head works A head work is a diversion provided over a main canal to raise the water level in the canal and to divert the water to branch canals or distributries The examples includes head Faqirian

7. Main canals Main canal receives its water supply directly from the river through a dam or a barrage Direct irrigation usually not carried out from the main canal therefor there are no canal outlets on the main canal The examples include upper Jhelum, lower Jhelum, Upper Chenab, lower Chenab, upper Bari doab and lower Bari doab

8. Branch canal Branch canal take off from the main canal through divergent structure such as head works and convey water to different parts the irrigated area through distributaries The branch canal usually are not provided with outlets for delivery of water to the fields excepts special cases These include Gugera and Rakh branch canals

9. Major distributary Major distributary (usually called distributaries or rajbah ) take off canal and some times from main canal and supply water to miner distributaries or directly to the main water courses through canal outlets Examples of major distributaries ar e Niazbeg,Shahkot and Nasrana

10. Minor distributary Minor distributaries(usually called minors ) take off from major distributaries and rarely from branch canal These supply water to water courses for irrigation Examples include Kamogil minor and Thatti minor as the minor distributaries of Niazbeg distriburay

11. Water courses A water course is defined as any channel that receives water from a canal or distributary and leads to the farms and fields It is operated and managed by the provincial irrigation department (PID) but maintained by the formers One or more water courses based on the size of irrigated area serve each village

12. Field channel Field channel or former branches carry water to the individual field form the main water courses These are constructed , operated , and maintained by the formers themselves individuals or a groups Generally the size of field channel as the same as that of main water courses because they have carry full flow received from the main water courses