Index Irrigation Engineering
- Introduction, Irrigation Techniques and quality of Irrigation water
- Water Requirement of crops
- Canal Irrigation system and design of Irrigation channels
- Rivers, Their behavior , Control and training
- Diversion Head works
- Cross drainage works
- Gravity Dams
- Theory of seepage
Introduction
- Water is greatest resource of humanity
- Largest use of water in the world is made for Irrigating lands
- Irrigation is nothing but “ a continuous and a reliable water supply to the different crops in accordance with their different needs” सिंचाई कुछ भी नहीं है, लेकिन "एक निरंतर और एक विश्वसनीय पानी की आपूर्ति उनकी विभिन्न आवश्यकताओं के अनुसार विभिन्न फसलों के लिए"
- Adoption of irrigation practice is not
new to our country for example, the most famous old irrigation work which
is functioning today is the ‘Grand Anicut (कल्लनई बांध)’ which was built by Cholas
in first A.D on the Cauvery river.
उदाहरण के लिए, हमारे देश में सिंचाई अभ्यास को अपनाना कोई नई बात नहीं है, आज का सबसे पुराना पुराना सिंचाई कार्य जो ग्रैंड एनीकट ’है जो कावेरी नदी पर पहले A.D में चोल द्वारा बनाया गया था। - Importance of irrigation was well
recognized by Mughal and as such , the Western Yamuna canal which was
built by Ferozshah Tughlaq in year year 1355 was renovated by Akbar.
सिंचाई के महत्व को मुगल द्वारा अच्छी तरह से पहचाना गया था और इस तरह, पश्चिमी यमुना नहर जो कि वर्ष 1355 में फिरोजशाह तुगलक द्वारा बनाई गई थी, अकबर द्वारा पुनर्निर्मित की गई थी। - During the British regime, the 1040 km long Upper Ganga Canal System , the longest in the world was completed in 1854.
Definition
– Irrigation may be defined as the artificial application of water to the soil
or land for the growth of agricultural crops. कृषि फसलों की वृद्धि के लिए सिंचाई को मिट्टी
या भूमि को पानी के कृत्रिम अनुप्रयोग के रूप में परिभाषित किया जा सकता है I
Necessity
of Irrigation in india
- More than 70% of our population, directly or indirectly depends on agriculture and remaining depends indirectly on agriculture हमारी आबादी का 70% से अधिक प्रत्यक्ष या अप्रत्यक्ष रूप से कृषि पर निर्भर है
- The geographical conditions, especially the nature of monsoon rainfall, in India make irrigation indispensable for sustainable agricultural development. Unfortunately, rainfall in India is uncertain, unreliable, irregular, variable, seasonal and unevenly distributed.
भौगोलिक परिस्थितियाँ, विशेषकर भारत में मानसूनी वर्षा की प्रकृति, टिकाऊ कृषि विकास के लिए सिंचाई को अपरिहार्य बनाती है। दुर्भाग्य से, भारत में वर्षा अनिश्चित, अविश्वसनीय, अनियमित, परिवर्तनशील, मौसमी और असमान रूप से वितरित की जाती है।
Advantages
of Irrigation
a) Increase
in food production
b) Elimination
of mixed cropping – Mixed cropping means sowing together of two or more crops
in the same field when weather conditions are not favorable for particular type
of crop. Mixed cropping is eliminated if we have good irrigation facility. मिश्रित फसल का मतलब है कि एक ही खेत में दो या दो से अधिक
फसलों की बुवाई जब मौसम की स्थिति विशेष प्रकार की फसल के लिए अनुकूल न हो।
c) Domestic
water supply
d) Revenue
generation
e) Inland
Navigation
f) Generation
of Hydro-electric power
g) Afforestation.
Types of
irrigation
·
Irrigation is classified in two ways
(1)
Surface irrigation
(2)
Sub- Surface irrigation
Surface
Irrigation
- In this method irrigation water is
distributed to the agricultural land through small channels which flood
the area up to a required depth . इस विधि में
सिंचाई का पानी कृषि योग्य भूमि को छोटे चैनलों के माध्यम से वितरित किया
जाता है जो एक आवश्यक गहराई तक क्षेत्र को बाढ़ कर देता है
- Water is applied and distributed
either by gravity or pumping.
- This method is suitable for low to
moderate infiltration capacities and lands with uniform terrain. यह विधि कम से मध्यम और समान भूभाग वाली भूमि के लिए
उपयुक्त है।
- Divided into two types Lift and Flow
irrigation
- Lift Irrigation – Water available at lower level is lifted to a higher level by mechanical or manual means and than supplied for irrigation.
- Flow Irrigation – Water
available at higher level is supplied to a lower level by the action of gravity
- Flow irrigation further subdivided
into Flood and Perennial irrigation.
- Flood / Inundation
Irrigation - It is used when water is available for
limited period and land is
submerged with water during rainfall.
- Perennial irrigation - in this irrigation water source is
constant and continuous available so water can be applied at any time.
- Perennial irrigation divided into Direct
(by diverting the river runoff into main canal) and storage ( by making
reservoir to store water) irrigation.
Sub-Surface
Irrigation
- In this method water is directly
applied to the root zone of crops . इस विधि में
पानी सीधे फसलों के मूल क्षेत्र जड़ों में लगाया जाता है।
- Water flows underground and
nourishes plant roots by capillarity. पानी भूमिगत बहता है और कपिलैरिटि द्वारा पौधे की
जड़ों को पोषण देता है।
- This method is suitable for soil
which are highly permeable .
- it may be divided into two following
types
- Natural Sub -irrigation - Leakage water from channels during its
passage through sub soil irrigates crop sown on lower lands. उप-भूमि के माध्यम से अपने मार्ग के माध्यम से चैनलों
से रिसाव पानी निचली भूमि पर बोई गई फसल की सिंचाई करता है।
- Artificial sub- irrigation - in this method a system of pipes drains is artificially laid below the soil. This method is costly and recommended in areas where crops provide high return. इस विधि में पाइप नालियों की एक प्रणाली को कृत्रिम रूप से मिट्टी के नीचे रखा जाता है। यह विधि उन क्षेत्रों में अनुशंसित है जहां फसलें उच्च रिटर्न प्रदान करती हैं।
Irrigation Techniques / Methods
There are various ways in which the
irrigation water can be applied the fields.
1) Free
Flooding
2) Border flooding
3) Check
flooding
4) Basin
flooding
5) Furrow
irrigation method
6) sprinkler method
7) Drip
irrigation
(1) Free
Flooding / Ordinary flooding –
- In free flooding method water is applied to the land from field ditches without any check or guidance to the flow so there is no control over flowing water. मुक्त बाढ़ विधि में भूमि पर पानी लगाया जाता है किसी भी जाँच या मार्गदर्शन के बिना क्षेत्र की खाई से प्रवाह इसलिए बहते पानी पर कोई नियंत्रण नहीं है
- Also known as wild flooding
- High evaporation and high infiltration losses.
- Efficiency is low
- Used in rolling lands/Undulating ground
- Used in closed growing crops/ seed driven crop.
( 2) Border Flooding –
- The land is divided into numbers of strips , separated by low levees called borders. भूमि को स्ट्रिप्स की संख्या में विभाजित किया जाता हैi
- Area between ditches is known as strip
- Length of strip 100 m to 400 m
- Width of strip 10 m to 20 m
- There is control over water
- This method is broadly used in India.
- Time required by water to cover the given area of land is
t
= 2.303(y/f)log(Q/Q – fA)
Where y = depth of water applied
f = infiltration capacity of soil
Q = Design discharge
A = Given area of land
( 3)
Check Flooding –
- Water is controlled by use of low andcross levees
- Confined area between levees lies between 0.2 hectare to 0.8 hectare
- Suitable for both permeable and less permeable soils.
( 4)
Basin Flooding-
- Special type of check flooding
- Specially adopted for orchard ( बगीचे) trees
- Shape of basin may be regular or irregular
( 5)
Furrow Irrigation –
- Furrows are small narrow channels. फरोज छोटे संकीर्ण चैनल हैंI
- Depth varies 8 cm to 30 cm
- Type of natural sub-surface irrigation
- Less evaporation losses but high infiltration losses
- Example – potato, radish, carrot etc
( 6)
Sprinkler method-
- In this method water is applied in the form of spray. इस विधि में पानी स्प्रे के रूप में लगाया जाता है I
- Pressurized method of irrigation
- Efficiency is approximately 80%
- Used for growth of tea and coffee
- Used for highly erodible soil
7) Drip
Irrigation/Trickle Irrigation-
- Method of artificial sub-surface irrigation
- Water is applied directly to the root zone. पानी सीधे रूट ज़ोन में लगाया जाता है I
- Negligible infiltration & evaporation losses
- Efficiency approximately 100%
- Using the area of having scarcity of water and for high return crops
