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WRE – IUNIT VIUNIT‐ VI
P f S S JAHAGIRDARProf S S JAHAGIRDARBE (CIVIL), ME(ENV.),PhD(persuing)NK Orchid college of Engg and Tech SolapurNK Orchid college of Engg. and Tech. , Solapur
ContentsTypes of irrigation methods
Classification of irrigationClassification of irrigation methods
A ) Wild Flooding ) gUncontrolled Flooding
Wild Floodingd ood gWater is applied by spreading on land.No preparation in the form of levees No preparation in the form of levees or borders or ditches.Water can be directly applied from natural stream or river during floodnatural stream or river during flood.Suitable for smooth and flat land.Wastage of water .
B ) Controlled FloodingB ) Controlled Flooding 1. Free flooding method
Free Floodingee ood gAlso known as irrigation by plots.Water is spread on the land with proper methods to control depth of proper methods to control depth of application.All methods of controlled flooding requires preparation of land requires preparation of land .Land is divided in to small strips by p ylevees.
2 Contour laterals2. Contour laterals
Contour lateralsCo tou ate a sApplicable for steeper terrain.pp pField is divided in to small contour lateralslaterals.Spacing of contour laterals depend uponp g p p
1. the prominent grade of the field between two adjacent ditches or laterals between two adjacent ditches or laterals,
2. the uniformity of slope and y p3. the soil type
3. Border strip method3 o de st p et od
Border strip methodo de st p et odFarm is divided into series of stripsWidth= 10 to 20 mL th t Length = 100 to 300 mStrips are separated by leveesStrips are separated by leveesFor applying water through supply channel earth or concrete channel is providedprovided
4. Check flooding
Check floodingC ec ood gLarge stream discharges water into relatively level plot surrounded by levees or checkslevees or checksWidth of levees at the base = 2 to 3 mHeight = not more than 25 to 30 cm highhighMethod is most suitable for permeable psoil as large amount of water is applied.
5. Basin flooding
Basin Flooding as ood gSpecial form of check flooding applied to orchards.
f d f hBasins are formed for each tree.W t i li d th h Water is supplied through a supply ditchsupply ditch.No. of basins can be interconnected
6. Zig zag method6 g ag et od
Zig Zag methodg ag et odSpecial method of floodingWater takes circuitous path before reaching dead end of plotreaching dead end of plot.Area is divided in to square or qrectangular plots.S it bl f l ti l l l l tSuitable for relatively level plotUnsuitable for modern farming with Unsuitable for modern farming with machinery.
7. Furrow method
Furrow methodu o et odUsed for row crops like maize, jawar, sugarcane, cotton tobacco ground nuts potatoes etccotton, tobacco, ground nuts, potatoes etc.½ to 1/5 of surface is wetted therefore evaporation l d dlosses are reduced.Length of furrow varies from 3 m or less – for gardensAs much as 500 m for fields crops.5 pCommon length = 100 to 200 m.No wastage of landNo wastage of landLess labour required
8. Contour farming
Contour farmingCo tou a gPracticed in hilly areas with steep y pslopes.
ld dField operations are done across the slope instead of uphill or the slope instead of uphill or downhill.Strips are also known as terrace or b hbenches.
C) Subsurface methods)1) Natural sub surface irrigation
* Water reaches below the land f f l surface from natural resources
such as streams lakes ponds etcsuch as streams, lakes, ponds etc.* Water seeping may raise the Water seeping may raise the water table and water may be available for plants in the root zonezone.
2) Seepage channels
Channels are spaced 15 to 100 m apartapart.Depth of channel varies from 0.25 pto 0.50 m.W t t bl i i t i d th Water table is maintained near the root zone of the crop.
3) Drip or trickle irrigationTo be covered in next class along with sprinkler irrigationalong with sprinkler irrigation.
University questionsU e s ty quest o sWhat is meant by surface and sub surface irrigation? What are their types? Discuss briefly the various techniques used yp y qfor distributing water in the farm.
(Nov 2009, 7 marks)What is meant by ‘border flooding’? How does it differ from ‘check flooding’ and ‘free flooding’? Draw suitable sketches to explain these methods to explain these methods.
(Nov 2007 8 marks)Discuss in brief various methods of surface irrigation. Discuss in brief various methods of surface irrigation.
(May 2007, 8 marks)Write short not on ‘Furrow irrigation’ g
(Nov 2006, 4 marks)