Irrigation is the process of supplying dry land with water through artificial means like pipes, hoses or ditches. Common irrigation methods include flooding, sprinkler, drip/trickle, and furrow irrigation. Factors that influence irrigation include surface slope, roughness, water depth, field size and shape, discharge rate, and field erosion resistance. Proper irrigation conserves water, increases crop yields, reduces costs, and prevents land degradation.

1. IRRIGATION
PRESENTED BY
AGLAIA

2. What is irrigation ?
• It is the process by which water is brought to dry land
through artificial means, such as pipes, hoses or ditches.
• The land that is being irrigated usually contains crops, grass
or vegetation that would not usually receive enough water
from rainfall or other natural sources.
• Sometimes the reason to irrigate a portion of land is that it
happens to be a dry season, or the land never would receive
enough water on its own to be fertile.
• The water that is used for irrigation might be taken from
nearby lakes, reservoirs, rivers or wells.

3. Irrigation
methods
Flooding methods
Sprinkler IrrigationSub surface Drip IrrigationSurface Irrigation
Controlled flooding
Contour
laterals
Border
strips
Free
flooding
Wild flooding
Contour farmingFurrow methods
Check
flooding
Basin
flooding
Zig zag
method

4. Surface Irrigation
• In this method water flows and spreads over the surface of the
land.
• Varied quantities of water are allowed on the fields at different
times.
• Hence, flow of water under surface irrigation comes under
unsteady flow.
• various factors which are involved in the hydraulics of surface
irrigation.
1. Surface slope of the field.
2. Roughness of the field surface.
3. Depth of water to be applied.
4. Length of run and time required. v) Size and shape of water-
course.
5. Discharge of the water-course, and
6. Field resistance to erosion.

6. subsurface irrigation
• It is a method of providing water to plants by raising the
water table to roots of the plants or by carrying moisture
to the root zone by perforated underground pipe
• It is also known as sub irrigation

7. Drip or Trickle Irrigation
• In this method irrigation water is conveyed on the surface
in 12 to 16 mm diameter tubing’s fed from large feeder
pipes.
• The water is allowed to drip or trickle slowly through the
nozzle or orifices at practically zero pressure.
• In this way the soil in the root-zone of crops is constantly
kept wet.
• By using this method crops can be grown successfully over
the saline lands also.

8. • This method has been found to be of great value in
reclaiming and developing desert and arid areas.
• The main drawback of this method is its high cost.
• But with growing realisation of the value of water this
method has been introduced in other countries of the
world particularly in desert areas.
• The method is still in initial stages of development in our
country.

10. Advantages
• It helps in optimum utilization of irrigation water by
reducing percolation and evaporation losses.
• There is no chance of land getting waterlogged.
• Crop yield is substantially increased.
• It makes possible to go cash crops.
• The fields do not get infested with weeds and pest.
• It helps in economical use of fertilizers.
• The fields do not get eroded or degraded.

11. Sprinkler Irrigation
• In this method an attempt is made to simulate natural
rainfall.
• Irrigation water is applied to the land in the form of a
spray.
• Sprinklers can be used on all soil types of any
topography.

13. Advantages of the Sprinkler Irrigation
• There is no erosion of soil.
• Fertilizers are used economically since they can be
injected through the water.
• Water can be applied uniformly and in controlled manner.
• This method is natural and helpful in sowing stage.
• This method can be used on any type of field.
• There is good saving of water.

14. Disadvantages of Sprinkler Irrigation
• Initial cost of the system is rather high.
• Any cost of power to provide pressure must be added to
irrigation chargers.
• Perforations in the pipe may choke up.
• Labour is required to move the pipes and plant.
• Water supply has to be free from sediment to avoid choking
of nozzles etc.

15. Flood irrigation
• In this method water is delivered to the field by ditch,
pipe, or some other means and simply flows over the
ground through the crop.
• Although it is an effective method of irrigation it is
certainly not efficient compared with other options.
• In this only half of the water applied actually ends up
irrigating the crop.
• The other half is lost to evaporation, runoff, infiltration of
uncultivated areas, and transpiration through the leaves of
weeds.

16. Furrow irrigation
• It is an irrigation where farmers flow water down
small trenches running between their crops.
• It works well for row crops, tree crops, because
water does not directly contact the plants, crops
that would be damaged by direct inundation by
water such as tomatoes, vegetables, potatoes and
beans.

18. Advantages to furrow irrigation
• lower initial investment of equipment
• minimizing water loss.
• lower pumping costs.
• It can minimize irrigation costs and chemical leaching
and result in higher crop yields.

19. Disadvantages of Furrow Irrigation
• The difficulty of moving farm equipment across the
furrows;
• The added expense and time to make extra tillage
practice.
• An increase in the erosive potential of the flow.
• level and remove any small hills for easy flow of water.
• They are difficult to automate, particularly with regard
to regulating an equal discharge in each furrow.

20. Contour farming
• The practice of tilling sloped land along lines of consistent
elevation in order to conserve rainwater and to
reduce soil losses from surface erosion.
• These are achieved by means of furrows, crop rows, and
wheel tracks across slopes, all of which act as reservoirs
to catch and retain rainwater, thus permitting increased
infiltration and more uniform distribution of the water.

22. Advantages
• Improve irrigation system and conserve water.
• Keep valuable top soil in place on sloping lands.
• Slows down water to settle in to the soil.
• Prevent formation of rills and gullies.
• Reduce labour and harvest easier.
• Improve appearance of land.

23. Wild Flooding
• This method of irrigation consists in turning the water
onto natural slopes without much control or prior
preparation.
• It is usually waste of water, and unless the land is
naturally smooth, the resulting irrigation will be quite
uneven.
• It is used mainly for pastures and fields of native hay on
steep slopes where abundant water is available and crop
values do not warrant more expensive preparations.

25. Controlled flooding
• It is relatively inexpensive because it requires minimum
of preparation.
• Water is brought to the field in permanent ditches and
distributed across the field in smaller ditches spaced to
conform to the topography, soil, and rate of flow.
• If the flow is too rapid, some of the water will not have
time to infiltrate and surface waste will occur at the
lower edge of the field.
• If flow is too slow, excessive percolation will occur near
the ditch, and too little water will reach the lower end of
the field.

27. Free Flooding
• This method consists of applying the water by flooding
the land of rather smooth and flat topography.
• In free flooding method water is applied to the land from
field ditches without any check or guidance to the flow.

28. Contour laterals
• It is as special types of free flooding in which the
field channels or laterals are aligned
approximately along the contour lines.
• In this methods irrigation is possible only in one
direction.

29. Border Strip Method
• In this method a field is divided into number of strips.
• The width of strip varies from 10 to 15 metres and length
varies from 90 m to 400 m.
• Strips are separated by low embankments or levees.
• The water is diverted from the field channel into the
strips.
• The water flows slowly towards lower end, wetting the
soil as it advances.
• When the slope is steeper, special arrangement is made to
prevent erosion of soil.

30. •This method is suitable on the fields where soil is
sufficiently capable to absorb the water.
•To divert water into the strip and to cutoff the
water supply a gate is provided in the field.
• Extra water is generally removed from the strip by
means of a collecting drain.

31. Check flooding
• it is accomplished by turning water into relatively level
plots, or checks, surrounded by levees.
• If the land is initially level, the plots may be rectangular
but with some initial slope the checks will usually follow
the contours.
• It is useful in very permeable soils where excessive
percolation might occur near a supply ditch.
• It is also advantageous in heavy soils where infiltration
would be inadequate in the time required for the flow to
cross the field.
• In this the check is filled with water at a fairly high rate
and allowed to stand unit the water infiltrates.

33. Basin flooding
• The basin flooding method is check flooding adapted to
orchards.
• Basins are constructed around one or more trees
depending on the topography, and the flow is turned
into the basin to stand until it infiltrates.
• Portable pipes or large hoses are often used in place or
ditches for conveying water to the basins.

35. Zig zag method
• In this agricultural area is subdivided in to small plots
by low bunds in zig zag manner.
• The water is supplied through the openings in the field
channel.
• The water flow in a zig zag manner and the opening is
closed when it reaches desired depth.

37. Thank you
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