After reading this essay you will learn about:- 1. Introduction to Irrigation 2. Necessity of Irrigation 3. Sources 4. Impact 5. Development and Scope 6. Methods 7. Role and Importance 8. Present Position and Progress.
- Essay on the Introduction to Irrigation
- Essay on the Necessity of Irrigation
- Essay on the Sources of Irrigation
- Essay on the Impact of Irrigation on Human Environment
- Essay on the Development and Scope of Irrigation in India
- Essay on the Methods of Irrigation
- Essay on the Role and Importance of Irrigation
- Essay on the Present Position and Progress of Irrigation in India
1. Essay on the Introduction to Irrigation:
Soil, seed and water are the basic requirements of any agricultural production. In addition, fertilisers, insecticides, sunshine, suitable climate and human labour are also needed.
Water is essential for plant growth as it performs the following functions:
(i) It provides moisture for germination of seeds, and chemical and bacterial processes during plant growth.
(ii) It cools the soil and makes the environment more favourable for plant growth.
(iii) It washes out completely or dilutes salts in the soil.
(iv) It helps in tillage operations.
(v) It enables application of fertilisers.
(vi) It reduces the adverse effects of frost action on plant growth.
In several parts of the world, the moisture available in the root-zone soil may not be sufficient to meet the requirements of the plant life. To make up this deficiency, water needs to be added to the root-zone soil. This artificial application of water to land for supplementing the naturally available moisture in the root-zone soil for the purpose of agricultural production is termed irrigation.
Irrigation water delivered into the soil is usually more than the crop requirement. Sometimes, soil has more water, naturally, than is required for healthy growth of the crop. This excess water is as harmful to the growth of crop as lack of water.
The natural drainage such as rivers, if existing in the vicinity of the irrigated land, can remove this excess water. However, in the absence of natural drainage, the excess water has to be removed artificially.
The artificial removal of the excess water is termed drainage which, in general, is complementary to irrigation. The object of providing irrigation and drainage is to help nature in maintaining moisture in the root-zone soil within the range required for optimum crop production.
2. Essay on the Necessity of Irrigation:
With increase in the world population, the demand for food and fibre also increases. Rainfall does not always occur in right amount at the time when crops need water. Thus, there is always a need of irrigation in most parts of the world. This is true for India as well due to erratic behaviour of its south-west monsoon and its ever-increasing population.
The average annual rainfall in India is 1,143 mm which varies from 11,489 mm in Cherrapunji region of Assam to 217 mm in Jaisalmer region of Rajasthan. Further, 75 to 90% of the annual rainfall occurs during 25 to 60 rainy days of the four monsoon months from June to September. There is also a large variation from year to year.
Since 1801, there have been 37 drought years in India. The severe drought of 1987 and very good monsoon (resulting in floods at several places) in 1988 followed by ten continuous good monsoon seasons are examples of complete uncertainty of south-west monsoon in India.
Dependability of rainfall is, therefore, low from agricultural point of view. Also, for a large part of any crop season, the water needs of a crop exceed the available precipitation. These inadequacies of rainfall make irrigation very essential for increasing food and fibre production.
The need and importance of irrigation in India can be appreciated from the facts that:
(i) About 45 % of agricultural production is still dependant on uncertain rains,
(ii) The country would need to produce 277 million tons (against the production of about 200 million tonnes for 1998-99) of food to meet the per capita requirement of 225 kg per year for an estimated population of 1231 million in the year 2030,
(iii) About 70% of the country’s population is employed in agricultural production, and
(iv) The export of agricultural products earns a major part of foreign exchange.
Usefulness and importance of irrigation can be appreciated by the fact that without irrigation it would have been impossible for India to have become self-sufficient in food with its huge population. Primary source of prosperity in Punjab is irrigation.
3. Essay on the Sources of Irrigation:
Depending on the availability of surface or ground water type of relief, soils and the moisture requirement of crops, various types of irrigation are practiced in India, more important among these are canals wells and tanks.
Wells provide the most widely distributed source of irrigation in India. Wells make use of the underground water. Well irrigation, therefore, is possible even in low rainfall areas provided sufficient quantity of ground water is available. Well irrigation is also within the reach of small farmers. It accounts for about 40 per cent of the total irrigated area in the country.
Canals are the other important source of irrigation. India has one of the world’s largest canal system? Stretching over more than one lakh km and serving: more then.20 million hectares.
Canals are of two types:
(a) Inundation canals, and
(b) Perennial canals.
Canals taken out from rivers without any regulating system are called inundation canals. Perennial canals too are taken off from perennial rivers or reservoirs with a wet system to regulate the flow of water, which is maintained throughout the year.
Tank irrigation is the most feasible and widely practiced method of irrigation in States like Tamil Nadu, Karnataka, Orissa, etc. Tank irrigation involves a high rate of evaporation and occupation of fertile land particularly as the depth of most of the tanks to shallow and the water spreads over a large area.
Therefore, wherever canal irrigation has been introduced, tanks have been reclaimed for cultivation. The proportion of tank irrigation to the total irrigation capacity, therefore, has fallen over the years.
4. Essay on the Impact of Irrigation on Human Environment:
An irrigation project, like any other water resource project, is constructed for the well-being of people, and has definite impact on the environment. The developmental activities cannot be stopped on environmental considerations alone. One should, however, appreciate that both developmental activities and an intact environment are equally important for the sustained well-being of people.
Following are die advantages of providing irrigation in an area:
(i) It provides protection against famine.
(ii) It increases agricultural production and its quality and, thus, adds to the national economy by substituting imports, and generating exports of food and non-food agricultural products.
(iii) It reduces rural poverty by creating additional employment in the sectors of main agricultural activities and related activities of input supplies and processing and marketing of agricultural products.
(iv) Inspection roads constructed for the irrigation works can be used by the people of the area and, thus, irrigation helps in improving the communication system of the region.
(v) Irrigation works can also be used for hydropower generation, inland navigation, industrial and domestic water supply, flood control, etc.
As a result of these benefits of irrigation, there are permanent gains in the life-style of rural population due to increased prosperity. However, there are some disadvantages associated with irrigation facilities which cause considerable increase in water-borne and water-related diseases.
Excessive surface water irrigation can lead to waterlogging of the cultivable land making it unsuitable for cultivation. There can be some adverse effects on the environment too which may adversely affect the human beings in the long run. With proper planning, these disadvantages can, however, be minimised, if not eliminated completely.
5. Essay on the Development and Scope of Irrigation in India:
Irrigation has been practiced throughout the world since the beginning of civilisation. In India, the Grand Anicut across the river Cauvery was constructed in the second century. There were a large number of water tanks in peninsular India and several inundation canals (such canals draw their supplies from a river only during the high stages of the river) in northern India.
The Upper Ganga canal, the Upper Bari Doab canal and the Krishna and the Godavari delta systems were built between 1836 and 1866. The famines of 1876-78, 1897-98 and 1899-1900 led to the setting up of the first Irrigation Commission in 1901.
In 1901, the total gross irrigated area was only 13.3 Mha (million hectares) which increased to 22.6 Mha in 1950 as a result of a spurt in protective irrigation schemes. The Bengal famine of 1943 made the authorities appreciate the urgency of increasing agricultural production to meet the needs of the growing population.
After independence in 1947, an era of planned development in irrigation started with the first five-year Plan in 1951. Giant projects like the Bhakra-Nangal, Hirakud, Damodar valley, Nagarjunasagar, Rajasthan canal, etc., were taken up.
As a result, the irrigated area increased from 22.6 Mha in 1951 to 87.8 Mha in 1995. The total ultimate irrigation potential is estimated at 115.54 Mha of which 58.47 Mha would be from major and medium irrigation schemes, and the remaining from minor irrigation schemes.
Salient details of some major dams of India are given in Table 1.1.
Command Area Development:
The irrigation potential created by the construction of a large number of irrigation projects in India has almost quadrupled since independence. It has, however, always remained under-utilised, and the optimum benefits by way of increased production have not been fully realised. Against the world average of about 5 tonnes of agricultural production per hectare of irrigated land, India produces only about 2.2 tonnes of crop per hectare of irrigated land.
The following have been identified as the main causes for these deficiencies:
(i) Need for modernisation of the old irrigation systems.
(ii) Lack of adequate drainage which results in waterlogging of the cultivable land.
(iii) Inadequate on-farm management of water.
(iv) Lack of suitable infrastructure and extension services.
(v) Poor coordination amongst the concerned organisations in the command areas.
Gross command area (or command area) of an irrigation system is the total area which can be economically irrigated from the system without considering the limitations on the quantity of available water. For optimising the benefits of available irrigation potential, an integrated command area development is always recommended.
The objectives of the command area development programme are as follows:
(i) Increasing the area of irrigated land by proper land development and water management.
(ii) Optimising yields by adopting the best cropping pattern consistent with the availability of water, soil and other local conditions.
(iii) Bringing water to the farmer’s fields rather than only to the outlets and, thus, assuring equitable distribution of water and adequate supply to tail-enders.
(iv) Avoiding wastage and misuse of water.
(v) Optimising the use of scarce land and water resources, including ground water where available, in conjunction with necessary inputs and infrastructure.
The command area development programme includes the following components:
(i) Modernisation and efficient operation of the irrigation system.
(ii) Development of main drainage system.
(iii) Construction of field channels and field drain.
(iv) Land shaping/levelling and consolidation of land holdings.
(v) Lining of field channels/watercourses.
(vi) Exploitation of ground water and installation of tube wells.
(vii) Adoption and enforcement of a suitable cropping pattern.
(viii) Enforcement of an appropriate rostering system on irrigation.
(ix) Making arrangement for timely supply of key inputs like credit, seeds, fertilisers, pesticides and implements.
(x) Strengthening of existing extension, training and demonstration organisations.
6. Essay on the Methods of Irrigation:
Irrigation water can be supplied to the land to be irrigated using one of the following methods:
(i) Surface irrigation methods which can be of the following types:
(a) Uncontrolled (or ‘free’ or ‘wild’) flooding method.
(b) Border strip method.
(c) Check method.
(d) Basin method.
(e) Furrow method.
(ii) Subsurface irrigation method.
(iii) Sprinkler irrigation method.
(iv) Drip (or ‘trickle’) irrigation method.
(i) Surface Irrigation Methods:
The history of irrigation begins with the application of water to the land in some kind of surface irrigation method. It is the oldest and most common method of irrigation. It, however, does not result in high levels of performance. In all the surface methods of irrigation, water is either ponded on the soil or allowed to flow continuously over the soil surface for the duration of irrigation.
(a) Uncontrolled Flooding:
In the uncontrolled flooding method of irrigation, water is applied to a field for irrigation without any land preparation and without any levees to guide or restrict the flow of water on the field. Water is simply admitted at one end of the field, thus, letting it flood the entire field without any control. This method generally results in excess irrigation at the inlet region of the field and insufficient irrigation at the outlet region.
This method has the advantage of low expenses on land preparation. Its main disadvantage is greater loss of water due to deep percolation and surface runoff. This method is, therefore, suitable when water is available in large quantities, the land surface is irregular, and the crop being grown is unaffected because of excess water.
(b) Border Strip Method:
It is a controlled surface irrigation method in which the farm is divided into a number of strips which are separated from each other by low levees (or ‘borders’ or ‘dikes’). These strips can be 3-20 m wide and 100-400 m long depending upon the unevenness of the land and the size of the supply channel.
However, narrow strips would require too many levees which would occupy lot of cultivable land. The length of the strip depends primarily on the infiltration rate of the soil and the slope of the land and is generally 60 to 120 m for more permeable sandy and sandy-loam soil and 150 to 300 m for less permeable clay loam and clay soils.
The strips do not have cross slopes but slope along the length depending upon the type of the soil. The strips should have much flatter longitudinal slope for less permeable clay and clay-loam soils, and flatter slope for more permeable sand and sandy-loam soils. Water from the supply channel is diverted to each of these strips along which it flows slowly towards the downstream end and, thus, irrigates the land.
(c) Check Method:
In this method, the land to be irrigated is divided into a number of almost levelled plots (kiaries) surrounded by levees. Water is admitted from the farmer’s field channels to these plots turn by turn so that the plots are flooded without overtopping the levees. Size of individual plots may vary from as small as one metre square (suitable for growing vegetables) to as large as one hectare or even more.
This method is suitable for wide range of soils ranging from very permeable to much less permeable soils. The farmer has good control over the distribution of water in different parts of his farm. The water application efficiency is higher for this method.
However, this method requires constant attendance for admitting and closing the supplies to the levelled plots. Also, there is some loss of cultivable area which is occupied by the levees. Sometimes, levees are made sufficiently wide to grow ‘row’ crops and, thus, compensate to some extent the loss of cultivable area on account of levees.
(d) Basin Method:
It is similar to the check method and is suitable for orchards which are irrigated by constructing a separate basin, usually circular in shape, for every tree. Basins of larger size can also be made in order to accommodate more than one tree. The basins are fed by field channels which receive water from the supply channel.
(e) Furrow Method:
Furrows are small field channels having uniform slope and are used to irrigate crops planted in rows. Water infiltrates through the wetted perimeter of the furrows and, thus, raises the moisture content of the root-zone soil of the plants which are planted in rows. The lengths of furrows may vary from 10 m to as much as 500 m, although, 100 to 200 m long furrows are more commonly used to avoid excessive percolation losses and soil erosion in the upstream reach of the furrows.
Furrows generally slope between 0.5 and 3.0%. If soil can resist erosion, furrows may have steeper slopes of about 6%. Spacing of furrows is decided by the spacing requirement of the row crops to be irrigated. The furrow water should not come in direct contact with plants or their roots.
Furrows in low permeability soil are generally 20 to 30 cm deep, whereas in other soils they are 8 to 12 cm deep. Water is fed to furrows from supply channel either through small openings made in the earthen banks of the supply channel, or by siphoning water from the supply channel to the furrows by means of a small diameter pipe of plastic or rubber.
Furrows wet only about half to one-fifth of the cultivated land and, therefore, reduce evaporation loss considerably. Furrows provide better on- farm water management and, thus, obtain high irrigation efficiency.
Following are the disadvantages of furrow method of irrigation:
(i) Possibility of increased salinity between furrows.
(ii) Loss of water at the downstream end unless end dikes are used.
(iii) The necessity of one extra tillage work, viz., furrow construction.
(iv) Possibility of increased erosion.
(v) Furrow irrigation requires reatively more labour.
(ii) Subsurface Irrigation:
In subsurface irrigation (or simply sub-irrigation), the water is supplied to soils directly under their surface. Moisture reaches the plant roots through capillary action. In this method, water is supplied to a network of ditches which are about 0.6 to 0.9 m deep and 0.3 m wide and with vertical sides.
These ditches are spaced 45 to 90 m apart. Sometimes, a distribution system of porous pipes is laid in the soil well below the ground surface. Soils which permit free lateral movement of water, rapid capillary movement in the root zone soil and very slow downward movement of water in the subsoil, are very suitable for sub-irrigation by porous pipes.
The cost of sub-irrigation is very high, but the water consumption is as low as one-third of the surface irrigation methods. The crop yield also improves. Application efficiencies generally vary between 30 to 80%. An impervious soil layer at about 2 m below the upper permeable soil layer would be favourable to sub-irrigation methods, if water is scarce.
(iii) Sprinkler Irrigation:
In this method, water is sprayed into the atmospheric air over the soil surface to be irrigated and allowed to fall on the soil surface at a rate less than the infiltration rate of the soil. Sprinkler irrigation provides controlled uniform application of water for frequent and light irrigation on shallow soils, sloping and undulating lands without having to develop them by land grading or levelling operation.
Rotating sprinkler-head systems are commonly used for sprinkler irrigation. Each rotating sprinkler-head applies water to a specified area size of which is governed by the nozzle size and the water pressure. Alternatively, perforated pipe can be used to deliver water through very small holes which are drilled at close intervals along a segment of the circumference of a pipe.
The trajectories of these jets provide fairly uniform application of water over a strip of farm land along both sides of the pipe. Because of the availability of flexible PVC pipes, the sprinkler systems can be made portable too.
Sprinklers have been used on all types of soils on lands of different topography and slopes, and for many crops. Sprinkler irrigation is normally recommended in the command areas where the land is highly undulating, water availability is poor, soils are sandy or shallow and where uniform application of irrigation water is required.
The following conditions are favourable for sprinkler irrigation system:
(i) Soils with very high infiltration rate.
(ii) Shallow soils, the topography of which prevents desired levelling at reasonable costs.
(iii) Undulating land and land with steep slopes where surface irrigation may result in excessive erosion.
(iv) Water is very scarce.
(v) Ground water is the source of irrigation water.
Following are the advantages of sprinkler irrigation:
(i) Saving of water and soil (due to no or negligible erosion of soil).
(ii) Saving in cost of land preparation.
(iii) Better control of soil moisture.
(iv) Frequent and light irrigation results in better crop yields.
(v) Easy and uniform application of water, fertilizers and pesticides.
Following are the disadvantages of sprinkler irrigation:
(i) Higher initial investment.
(ii) Higher power requirement.
(iii) Unsuitable for soils having low infiltration rate.
(iv) Poor application efficiency under high windy conditions and high temperature.
(v) Unsuitable for canal irrigation in which water is distributed by rotational supply system.
Because of its advantages, sprinkler irrigation is replacing the surface irrigation methods. In India, the gross area under spunkier irrigation has increased from 3 lakh hectares in 1985 to 5.80 lakh hectares in 1989, and is expected to further increase to about 20 lakh hectares by the turn of the 20th century.
(iv) Trickle (or Drip) Irrigation:
In the drip irrigation system, water is applied slowly and frequently to keep the soil moisture in the root-zone soil of the plant within the desired range. The water for irrigation is conveyed from the source to the plant root zone through a system comprising main line (37.5 to 70 mm diameter pipe), sub-mains (25 to 37.5 mm diameter pipe), laterals (6 to 8 mm diameter pipe), valves (to control the flow), drippers or emitters (to supply water at a desired rate of about 1 to 10 litres per hour to the plants), pressure gauges, water meters, filters (to remove all debris, sand and clay to reduce clogging of the emitters), pumps, fertiliser tanks, vacuum breakers and pressure regulators.
Flow is controlled manually or set to automatically deliver either:
(i) Desired amount of water for a predetermined time, or
(ii) Water whenever soil moisture decreases to a predetermined amount.
A line sketch of a typical drip irrigation system is shown in Fig 1.2.
Following are the advantages of this method:
(i) It saves water and improves water penetration.
(ii) It reduces weed growth.
(iii) Limited soil wetting permits uninterrupted agricultural operations.
(iv) Lower operating pressures and lower flow rates require lesser energy for pumping.
(v) It enhances plant growth and improves crop yield.
(vi) It does not require land preparation.
(vii) It does not cause soil erosion.
(viii) It improves fertiliser application efficiency.
Following are the main disadvantages of drip irrigation:
(i) It requires high skill in its design, installation and maintenance.
(ii) Initial investment cost is rather high.
(iii) The system is sensitive to clogging because of small openings used in the system.
Because of the obvious advantages of water saving and increased crop yield associated with drip irrigation, India has embarked on a massive programme for popularizing this method.
7. Essay on the Role and Importance of Irrigation:
Irrigation has two roles:
(i) Protective aspect, i.e. to make up the moisture deficiency in soils during the cropping season so as to ensure proper and sustained growth of the crops;
(ii) Additional land use aspect, i.e., to enable a second or third crop being raised on the land which could otherwise not be cultivated efficiently, more particularly during the post-or pre-monsoon period. Thus, irrigation, on the one hand, is an insurance against the vagaries of nature and, on the other, helps raise the productivity of land. Development of irrigation has conferred immense benefits to the Indian rural economy.
These benefits can be classified in two categories:
(A) Direct benefit:
It has helped in:
(a) Promoting the greater utilisation of land;
(b) Enlarging the average size of the farm;
(c) Generating demand for additional farm labour;
(d) Bringing a shift in crop pattern in favour of new and improved varieties of crops;
(e) Increasing additional productive investment; in farm business;
(f) Bringing favourable input-output ratio; and
(g) Widening the scope for increase in land revenue and other local receipts.
(B) Indirect benefits:
Irrigation has led to:
(a) A general expansion of secondary and tertiary activities in the area affected by it resulting in greater work opportunities leading to a reduction in migration .of rural poor to the urban areas;
(b) More employment to both family and hired labour;
(c) Higher value of output per industrial unit; and
(d) Higher turnover of business establishments in the project areas.
With the bulk of population living in villages, and a substantial proportion of national income oozing out of land, it is rightly said that nothing moves in the Indian economy unless agriculture moves.
And it is truism to state that agriculture cannot move unless water moves into agriculture. One need only recall the various ways in which irrigation can provide agriculture the basic wherewithal to realise the crucial relevance of water supplied in adequate quantity, and on time.
i. Pulling out of fatalism:
To inject dynamism in India’s traditional agriculture, it is necessary that an assured supply of water is made available, so that the agriculturist, prone to pessimism on account of uncertain rainfall, looks to his life and work with optimism.
The Indian farmer is neither un-enterprising, nor insufficient within the frame of very meagre existing factor availability. But he is up against the Nature’s bounty, unevenly distributed, which he alone cannot get over.
Hence the fatalism, and the gamble that goes with the undependable basic input of agriculture. It is only when the farmer sees a certain promise of his work and investment that he will be motivated to transform sand into gold.
Water being the primary factor, next only to land, it is its regular availability that alone can change the fatalistic outlook of the fanner. Irrigation in India will thus change the very ‘man’ in agriculture, and as a consequence the entire gamut of agricultural operations will undergo transformation for the better.
More crops and more production. Irrigation makes possible the growth of more than one crop where one is grown, and one or more where none is possible. Double and multiple cropping are of great significance where land is scarce as in India, and therefore not much can be expected in the direction of extensive cultivation. In brief irrigation makes intensive cultivation possible. This raises cropping intensity, and seeding the land with a variety of crops in a year.
More crops mean larger production. Obviously with no or more crops than one or none before, there should be increase in production. Again with water constraint removed, the crop-pattern tends to be of a sort that takes the best and the largest from the land. Small farmers to raise their output levels when water-supply is adequate. Their personal care and deep interest yield more returns than are possible in large farms.
ii. Raise productivity:
Irrigation also helps greatly in raising the yield of land. It enables, as has been (he case under the Green Revolution, the application of modern inputs and latest agricultural practices. Even at present the yield in irrigated area is much higher than in the un-irrigated area.
In foreign countries with very high yields, an assured supply of water has played a key role in this sphere, for example in Japan with high land-yield, 75 per cent of the area under agriculture is irrigated. In Egypt, another high up in the yield-profile, hundred per cent of the cultivated area is irrigated. Hence assured water supply is the basic factor in raising yield. If Nature does not provide, as is the case in India, irrigation has to be done by man.
iii. Promoting price-stability:
With irrigation facilities expanded and evenly spread, time-wise and crop-wise, there is bound to be lesser instability in agricultural production. This has a great bearing on the price situation.
When supplies of many agricultural products flow evenly over time, there are lesser chances of agricultural prices to fluctuate much. And since agriculture is die most important component of the total price situation, there is bound to be a certainty about the movements of prices.
In this way, though indirectly, irrigation will impart a strong element of stability to the overall price-level. So important is irrigation from this angle that the Sixth Plan envisaged “expansion in irrigation …. as a part if a price-stabilisation policy. It is so because, irrigation contributes substantially to the agricultural price stability, by removing to a large extent the elements of uncertainty in the agricultural production.”
iv. Large employment potential:
The construction and maintenance of irrigation projects, provide a large scope for employment This is particularly important as these projects are by and large located around villages. The employment potential exists because of many labour-intensive components of these projects. These, for example, consist of excavation of large network of small channels, construction of large masonry and concrete structures and large canals.
No doubt in certain types of work, as for example in large dams, some mechanisation is inescapable (for example special types of hydraulic structures) to ensure speedy completion and quality of work. How-ever, even in such cases a proper mix of capital-intensive and labour-intensive technologies can be so devised as to promote large employment.
In fact this course has already been tried with success in certain projects like Nagarjunasagar dam, Rajasthan canal project, Kadam dam, etc., where large human resources and most sophisticated construction equipment’s go together.
v. Helping small farmers:
Considering the smallness of marginal farmers, and small farmers in terms of the size of land who constitute a big majority among farmers, the most important way of adding to their income, is by making small farming a profitable proposition through intensive cultivation which depends almost wholly on the adequacy of water.
The modem techniques and practices, amply tested in some parts of India as also in countries like Japan and Taiwan etc. hold out a big promise in this respect.
Considering also the fact that Indian farmers are by and large inefficient in allocating factors or as Schultz would put it there are “comparatively few significant inefficiencies in the allocation of factors of production in traditional agriculture,” one may presume that with the addition of water, these farmers will perceive the opportunities of transforming agriculture into a modern one.
vi. Releasing land for non-crop uses:
More production through irrigation would imply lesser use of land. This would make available more land than at present for such purposes as animal husbandry, forestry and horticulture. A little calculation is enough to drive home this point.
If an average production of 3 tonnes-per hectare of food grains could be achieved on all our irrigated land (through modernisation of irrigation system and methods), the entire demand for food grains can be met, releasing large portions of remaining 100 million hectares of un-irrigated land for more rational and profitable uses.
This would also mean that the extension of agriculture into marginal and sub-marginal lands now taking place would not be needed, and thereby making such lands for use in lines where these can give better returns. As a result, we can have a vastly better animal husbandry based on richer pastures and unproved strains of cattle, sheep and goat, very much more forestry and very much more horticulture.
vii. Meeting the peculiar needs:
Water supply through properly devised schemes is required to meet certain peculiarities of the Indian situation. Its climate geography being governed by its location in the tropical and subtropical zones, there are many dry areas which need to be watered through artificial means.
Again despite considerable other advantages in terms of agricultural resources the soil lacks sufficient moisture, and therefore renders agricultural production not so efficient as in some other parts of the world.
Sandy soils, quite sizeable in themselves, need more and more frequent water as compared to that required for alluvial black soils. In this form irrigation serves as a protective agency making up the moisture deficiency of soils to ensure proper and sustained growth of crops.
Another peculiarity arises from the different nature of crops, requiring varying water supplies. An idea of the varied needs can be had from the different amounts of water in acre- inches for different crops: mustard 10.6; wheat 14.8; maize 17.8; groundnut 26.1; rice 41.7; cotton 42.2; and sugarcane 95.0. It is thus obvious that to meet these peculiar needs of the country, of its soil and its different crops, water supply has to be so controlled and its use so regulated that it is supplied in just the right quantity.
viii. Correcting the imbalances:
All the gains from irrigation listed above are possible only by redistributing equitably the water supplies over space and find such that existing imbalances are reduced considerably, if not removed altogether.
With 80-90 per cent of rainfall concentrated in four monsoon months, and with the central-western regions, belonging to the world’s wettest areas of the north-eastern parts, remaining a chronic drought area, the necessity of tapping surface as also ground-water is very much obvious.
This is in sharp contrast to the conditions prevailing in the United Kingdom where rainfall is more or less uniformly distributed throughout the entire year. The first thing to do then is to store water for use in the remaining eight months of the year.
Another thing to do is to transfer water from the surplus to the deficient areas, and the third is to meet the vagaries of the monsoon which shows itself in the following disturbing pattern of six years cut into two good years, two just ‘so so’ years and two of famines in large parts of the country.
Irrigation thus balances the imbalance of the otherwise generous Nature. And in doing so places water at the disposal of the people everywhere not only to eliminate natural famines, but more so to provide a basis for abundance.
From the above discussion, the need for irrigation is very much evident. Agriculturist turns optimist. Production and productivity rise. The needy farms get watered. Considerable land gets released for much better use in animal husbandry, forestry and horticulture.
Dry-lands get their thirst quenched. Different crops are fed as per the requirements of the healthy growth. Un-evenness and inequitable distribution of water get corrected, so that every land gets water. As a result, land comes alive. In fact, the man in agriculture flowers. And so does any and every Indian. Not incorrectly Sir Charles Trevelyan once remarked: “Irrigation is everything in India.” And we agree.
8. Essay on the Present Position and Progress of Irrigation in India:
After having taken up the importance of irrigation, we now asses the state of irrigation development in the country. This we do by describing the present position of irrigation facilities, and the progress made in them since 1950-51 when the planned development began.
Potential and Utilisation:
In stating the present state of affairs in respect of irrigation, we refer to the estimated potential, the actual potential and the utilisation of the created potential.
The ultimate irrigation potential has been estimated at 113.5 million hectares. Of this 58.5 million hectares are from major and medium schemes and 55 million hectares from the minor irrigation schemes. In addition, two schemes (Himalayan Rivers Development and Peninsular Rivers Development) have been prepared to augment the irrigation potential by 35 million hectares (25 million hectares from surface-water and 10 million hectares by increased use of ground-water).
These schemes envisage increase in the water resources through storage and inter-basin transfer from surplus to deficit and draught-prone areas. With this addition, the irrigation potential is expected to rise to 148 million hectares.
In this connection it may be useful to note that the irrigation potential is much larger than the present estimates. This conclusion is based on the fact that average annual precipitation (excluding evapotranspiration and soil moisture storage) has been estimated at 178 million hectare meters (or 1780 thousand pillion cubic meters) which contributes to the surface run-off and the ground-water recharge included in the annual hydrological cycle.
However, on account of the several limitations such as of topography, geology, etc., as also the present state of technology, the potential cannot be realised. But with the advancement of technology the estimate of the utilisable water will go up.
Potential created and utilized:
Of the ultimate potential of 113.5 million hectares, that which has been actualized is 74.3 million hectares (1987-88). With this much created potential, India ranks first among the countries of the world in respect of existing irrigation facilities. The potential is created both under the major and medium schemes as also under the minor schemes, with more under the latter. The created potential thus is about 66 per cent of the estimated potential.
As for the utilisation is concerned, it falls short of the created potential. In 1987-88 the utilisation at 66.2 million hectares was 90 per credit of the created potential. The utilisation was more in the land irrigated under minor schemes at more than 92 per cent as against over 82 per cent in case of the land under major schemes. (Table 2).In the year 2006-07 the total potential was 102.8 million hectares and actual utilisation was 87.2 million hectares.
Progress of Irrigation:
When we look at the development of irrigation over time since 1950-51, we find that some progress has in fact taken place, however, this has not been satisfactory, considering the potential of the country and the needs of agriculture.
i. Slow growth:
There is an increase in the irrigation potential created and the potential utilised, although the pace of growth has been slow. Plan- wise, the growth rate in respect of the created irrigation potential has remained low for long. The area under irrigation increased at the rate of just 0.7 million hectare per year during the First Plan period. It remained low at 0.5 and 0.9 million hectares per annum during the Second and the Third Plans respectively.
The annual average picked up slightly in the Fourth Plan period when it became 1.4 million hectares. The growth rate accelerated slightly to 1.6 million hectares per year during the Fifth Plan period and further to 2.2 million hectares during the Sixth Plan period. The Seventh Plan envisaged a growth rate of 2.S million hectares per year for the period 1985-90. In the year 2008-09, the total irrigation areas stood at 5485.80 thousand hectares.
In respect of the utilisation of the created potential, the picture is no different. The utilisation has often been low. For example, it was less than 90 per cent of the created potential in 1987-88. Over the years in the past the wastage of water not used for cultivation has been considerable.
As much as four to eight million hectares of land have remained without water for several years despite the facilities for irrigating them. This involves loss of resources already invested and loss of production which does not materialize.
ii. Higher growth of minor works:
Of the two categories of irrigation schemes, namely major and medium schemes, and minor schemes, there has been a slightly larger addition to the created irrigation potential on account of the minor schemes. This has been a feature of all the plans.
As a result of this, the irrigation potential created under the minor schemes stood at 42.4 million hectares (out of the total at 74.3 million hectares in 1987-88), as against 31.9 million hectares under the major and medium schemes. In respect of the utilisation of the created potential too, the minor schemes stand at a higher level. This too has been the case almost throughout the period in the past.
A higher growth in minor irrigation works has proved beneficial for the country, as also for the small/marginal farmers. Since these can be undertaken almost everywhere, these provide water to many places scattered throughout the country.
Again, since these involve such minor projects as dug-well, tube- wells, ponds, etc., these are within the reach of the farmers with small means. No doubt the major-medium works, being multipurpose, are useful also for the generation of electricity, flood control etc. However, strictly from the angle of supply water 10 many farmers and many places, minor works are a more attractive proposition.
iii. Uneven growth: crop-wise.
A feature of the growth irrigation having a close bearing on the cropping pattern, production and productivity, is its uneven spread in respect of different crops. Although all crops do not need equal watering, yet most of the crops particularly in the dry areas need more of it. But the sharing of increase in irrigation potential has been inequitable. Most of the irrigation capacity continues to be confined to food grains.
However, all food grains crops have not benefited equitably. A few crops have taken the lion’s share, leaving many high and dry. Wheat has benefited the most. This enabled the wheat farmers to make the best of the new agricultural technology which ushered in the Green a Revolution.
Rice, the staple food of the majority of population, has shown; a much less impressive growth. Jowar and maize, the poor man’s cereal, have faced the same fate. Worst is the case of pulses, the major supplier of protein for the vast vegetarian population.
Among non-food grains, some crops like groundnut, cotton and sugarcane have derived great benefits from the increase in the irrigation capacity. However, this has made little difference to the overall picture. With such unequal sharing of irrigation benefits, no wonder the productivity in a few crops has shown sharp rise, while in many a crops has not. As a result the productivity in general has not risen significantly.
iv. Uneven growth: region-wise:
Another unsatisfactory aspect of irrigation growth is the very unequal rates at which irrigation facilities have grown in different regions/states. No doubt in a vast country with diversified topography and differences in water-resources, there is bound to be some disparity and imbalances in the development of irrigation facilities.
Historical reasons to have contributed to it. States with good administration and therefore ability to investigate and implement irrigation schemes have gone much ahead of others.
Even so the efforts made since independence to correct the imbalances fell short of the needs. The growth of irrigation facilities in some states has been much slow and in some states much fast.
States like Punjab, Haryana, Uttar Pradesh and Tamil Nadu have progressed much more than many other states. There are states like Madhya Pradesh, Maharashtra and Gujarat which have to go a long way before they develop fully their water resources, and level up with the better-placed states.
v. Inadequate development/management of land and water:
Alongside the creation of irrigation capacity, albeit slow, some progress has also been recorded in the development of land around irrigation projects and management of water, to ensure better use of investments in irrigation. In this connection two programme, namely Command Area Development (CAD), and Flood Control, are important. Under CAD the aim has been to ensure that the command area of an irrigation project is ready to receive and beneficially use water supplies.
For this some success has been achieved in such fields as: consolidation of small and scattered holdings; scientific land Shaping; construction of water courses and channels to carry surplus water to individual fields; field drains to carry surplus water away from fields, etc. Besides, efforts have been made to provide inputs and marketing and other infrastructural facilities so that the farmers derive the optimum advantage of land and water.
In respect of Flood Control too something has been achieved in providing protection to large areas, some towns and many villages. Resources have also been provided for such measures as flood forecasting; flood warning; new embankments; drainage improvements; soil conservation, including afforestation, etc.
However, the progress has remained inadequate. In fact the damage from floods to the land, crops and property continues to be very large indeed. All in all, the efforts at making the best use of irrigation capacity have fallen short of the full utilisation of the created potential.
To sum up, some progress has indeed been made since independence. However, the achievement has not been satisfactory with much potential remaining untapped. Further, unfortunately the sharing of irrigation growth has not been equitable, crop-wise and region-wise. The measures to make the optimum use of water have also been inadequate. As such the progress leaves much to be desired.