Learn: Definitions of some more imporatant terms,Outlet factor,Paleo watering,Kor Watering,Kor Depth,


Some of the common terms usually used in regard to the watering of the fields have been explained here.

1. Outlet Factor.

  • This term has already been explained earlier. It is nothing but duty of canal water at outlet.

2. Paleo Watering.

  • This is the watering applied to the fields before sowing the crops.
  • This watering is given so as to develop sufficient moisture in the unsaturated zone of the soil so that seeds may germinate easily.

3. Kor Watering.

After sowing, when crops have grown a few centimetres this watering is given.

It is the first watering after sowing of the crop.

Depth of kor watering is always more than the subsequent watering tobe given to the crops in its growth or base period.

4. Kor Depth.

The depth of water applied during Kor watering is known as Kor depth.

5. Kor Period.

  • It is that initial part of the base period for a crop, in which Kor watering has to be necessarily given to the crop, otherwise its yield may be affected.
  • While designing the capacity of the canal, Kor watering is always taken into account.
  • Maximum canal discharge is required during Kor period as Kor watering has to be given in limited Kor period of the crop.
  • Kor watering requires maximum discharge in limited time.

6. Time Factor.

  • It is the ratio of the number of days the canal has actually run to the number of days or irrigation period.
  • For example, if irrigation period is 15 days and canal has run only for 10 days during it, the time factor would be 10 15 i.e., 2 3 .When we call days of irrigation, the day also includes the night.

7. Capacity Factor.

  • It can be defined as the ratio of the mean supply discharge to the full supply or capacity discharge of the canal.

8. Cumec-day.

  • It is the quantity of water supplied by one cumec discharge flowing for one-day.
  • It is equal to 8.64 hectare metre.

9. Root Zone Depth.

  • It is that maximum depth of the soil upto which roots of the crop extend and derive water from the soil.

10. Full Supply Co-efficient.

  • It is obtained by dividing area estimated to be irrigated during the base period by the design full supply discharge of the canal at its head during peak demand.
  • It is also sometimes referred as “duty on capacity”.

11. Nominal Duty.

  • In some areas farmers have to submit an application to the irrigation authorities, stating their water demands in advance of every crop season.
  • They are then issued permits authorising to use water.

12. Gross-Command Area (G.C.A.).

  • It is the total area over which water can flow under gravity.
  • Generally in a canal system, the whole area is divided into a number of watersheds and drainage lines.
  • The canal is located on the watershed so that water may flow from it on both the sides due to gravity.

13. Culturable Command Area (C.C.A.).

14. Incommand Areas.

  • In culturable command areas, there may be such areas where cultivation is possible but their levels are such that they cannot be supplied water under gravity.
  • With passage of time the incommand areas may become low due to shifting of soil by storms. Such areas may later be declared command areas and provided with irrigation water.

15. Culturable Cultivated Area.

  • It is the area in which crops are grown at a particular crop season or time.

16. Culturable Uncultivated Area.

  • It is that area where irrigation is possible but crops are not grown in a particular crop season.
  • This is the area which is given rest in a particular season.
  • In a canal system of irrigation, water is not supplied for full culturable land in a crop season.