Irrigation System

Basic Definitions

Net Area Sown: The physical extent of land on which crops are sown and harvested. It is the total area sown with crops and orchards at least once a year. Net Irrigated Area: The Area irrigated through any source at least once a year for a particular crop. Total/Gross Irrigated area: It is the total area under crops, irrigated once and/or more than once in a year. It is counted as many times as the number of times the areas are cropped and irrigated in a year. Total Net Un-Irrigated Area: Area arrived at by deducing the net irrigated area from the net sown Irrigation System area. Net Unirrigated Area = Net Sown Area – Net Irrigated Area Gross Unirrigated Area: Gross Unirrigated Area = Gross Sown Area – Gross Irrigated Area

 

The agriculture sector consumes 80% of the freshwater in India, and yet according to Niti Aayog, only around 52% of India’s agricultural land comes under irrigation (2022-23).

This means that it would be very difficult to bridge this gap and provide irrigation support to all farmers in India sustainably. Fully irrigating Indian agriculture, that too against the backdrop of water scarcity and limited efficiency in existing irrigation schemes, will be a defining challenge for India’s future.

Challenges of Irrigation in India

• Seasonal Nature of Monsoon – more than 3/4th of annual rainfall occurs during the 4 months.
• Water, Agriculture and Irrigation are state subjects, whereas the problems that India faces under each of these heads are national-level problems.
• Low Irrigation Cover:
  1. The Net irrigation cover is just above 50%. But Irrigation covers 33% of the gross cropped area.
  2. Inequitable distribution: More than 60% of irrigation water is consumed by rice & Sugarcane.
• Groundwater Depletion: Groundwater depletion is alarming at about 120cm/year in India on average. Groundwater contributes about 60%, all the other sources contribute the rest 40%, including, canals (24%), tanks (2%) and other sources.
• Poor Efficiency and Effectiveness

1. There is a gap between the Irrigation potential created and the Irrigation potential utilized. This shows the inefficiency of Irrigation systems.
2. Water Use Efficiency – India pumps twice as much groundwater as the US or China(above figure); the Situation is more alarming in North India.
3. The efficiency of surface irrigation systems can be improved from about 35-40% to around 50-60% and that of groundwater from 65-70% to 72-75%.
4. Land degradation: Water-logging and increased salinity.

• Unsustainable Policies

1. 1. 1. MSP – more MSP for water-guzzling rice and FRP for Sugarcane;
      2. POWER SUBSIDY – use of pumps to draw water

• Usage Disparity in Irrigation Systems:

1. • 1. Biases against rain-fed areas: Rain-fed Agriculture Atlas (By Rainfed Agriculture Network). They produce 88% of pulses, 40% of rice, and 64% of Cattle population. But miniscule procurement in rain-fed areas.
     2. Local disparities: For example, affluent upper-caste farmers with more clout and Farmers near the canal use it more and use it first.

• Regional Crisis:
• • • Maharashtra: one of the worst water-stressed states of India but it is also the largest state with sugarcane cultivation in the tropical region.
    • Similarly, sugarcane and paddy are commonly cultivated in highly water-stressed regions of the Cauvery basin, which spreads over the conflicting states of Karnataka and Tamil Nadu.
    • Much of Punjab is an extension of Rajasthan in terms of its agroclimatic zone, and yet it grows rice.

Types of Irrigation System

Surface Irrigation

Surface irrigation is where water is applied and distributed over the soil surface by gravity. It includes three types of irrigation systems:

1. Flood Irrigation
2. Furrow Irrigation
3. Surge Irrigation.

Flood Irrigation:

The field is essentially flooded with water which is allowed to soak into the soil to irrigate the plants. It is one of the oldest techniques known to man being simple and cheap.

Problems with Flood irrigation:

1. It can be extremely wasteful when it is not done with care.
2. Huge evaporation losses.
3. Increases salinity of the field.

Furrow Irrigation:

In Furrow irrigation, trenches or “furrows” are dug between crop rows in a field. Water seeps vertically and horizontally to refill the soil reservoir. Flow to each furrow is individually controlled.

Problem:

1. Ensuring uniform dispersion of water over a given field is difficult.
2. Increased potential for water loss due to runoff.

Surge Irrigation:

It is a variant of furrow irrigation where the water supply is pulsed on and off in planned periods. The wetting and drying cycles reduce infiltration rates resulting in faster advance rates and higher uniformities than continuous flow.

Subsurface irrigation –

Subsurface irrigation involves applying water from beneath the soil surface either by constructing trenches or installing underground pipes – upward movement of water by capillarity.

It includes two types of irrigation methods:

1. Ditch Irrigation:ditches are dug out and seedlings are planted in rows. The plantings are watered by placing canals or furrows in between the rows of plants. Siphon tubes are used to move the water from the main ditch to the canals.
2. Sub Irrigation or Seepage Irrigation: water is delivered to the plant root zone from below the soil surface and absorbed upwards. The excess may be collected for reuse.
   • Advantages: water and nutrient conservation, and labour-saving.
   • Problems: The outfitting cost is relatively high.

Types of Irrigations based on the source of water: Canal Irrigation: Water is generally sourced from weirs and dams built on rivers and streams, which are brought to the agricultural fields through canals. Well/Tube well irrigation: Utilising groundwater. Tank irrigation: Generally either rainwater-water or water from the local streams or canals can be stored in tanks for the dry seasons. This refers to tank irrigation.

Micro-irrigation:

Micro-irrigation refers to a slow application of water as discrete or continuous drips, tiny streams or miniature spray on, above, or below the soil by surface/subsurface drip, bubbler and micro-sprinkler systems.

Drip irrigation

Drip irrigation involves placing pipes with emitters alongside the plants. The water is supplied at regular intervals through these tubings along with additives such as fertilizers. It is applied through emitters connected to a water delivery line through low-pressure delivery.

1. Fertigation: the injection of fertilizers into an irrigation system
2. Chemigation: the injection of chemicals into an irrigation system. It is generally a more controlled and regulated process due to the nature of the chemicals used. Chemigation often involvesinsecticides herbicides, and fungicides, some of which pose health threats to humans, animals, and the environment.

Advantages of Drip irrigation:

1. It takes 1/3rd of the water.
2. The benefit-cost ratio of drip with fertigation is high.
3. It is especially advantageous for the wider spacing crops such as horticulture crops and grasses, where water and fertiliser loss is huge.

Sprinkler irrigation

Sprinkler Irrigation is used for uniformity on the undulating field. However, the evaporation losses are huge under sprinkler irrigation.

Sub-surface Porous Vessel Irrigation

Sub-surface porous vessels (SSPV) is a novel method developed in Rajasthan with Technical assistance from IIT-Jodhpur. It involves frustum-shaped vessels, at the mounds formed on land, with the storage of 8-9L water, wetting a radius of 1.25 metres of land. These mounds provide adequate moisture to the nearby fields slowly.

These are made of location-specific clay and sawdust, mixed in a proportion to suit the desert sand, press-formed to the frustum shape and baked at a temperature of 750-800^oC with the addition of a carbon layer in its structure.

• The average penetration of micro-irrigation in India is around5%. It is largely being promoted in arid and semi-arid regions, in the states of Karnataka, Telangana, Andhra Pradesh, Tamil Nadu, Maharashtra, Gujarat and Rajasthan.

Benefits Of Micro-Irrigation

Although the investment in a micro-irrigation system is a main concern, it gives great advantages in the long run.

1. Efficient deployment of inputs – water, fertilizers, labour;
2. A low flow rate is required, which helps in energy
3. Increase in crop productivity.
4. Increased income of the farmer in the longer run.
5. Reduction in losses: reduces conveyance losses, runoff, evaporation losses, seepage and deep percolation losses significantly

The Economic Survey (2019-20) has pointed out that micro-irrigation has saved irrigation water from 20 to 48%; energy saving from 10 to 17%; saving labour costs from 30 to 40%; saved fertilizers from 11 to 19% and increased crop production from 20 to 38%.

Challenges in Efficient Water Use

1. Declining landholdings and farm income: capability of the farmer to adopt expensive micro-irrigation systems. Unsustainable for very small land holding.
2. Credit unavailability makes technology upgradation a challenge.
3. Expensive micro-irrigation
   1. Initial Investment: micro-irrigation is expensive in terms of per hectare cost, and it further depends on the size of a farm as well as the type of crop grown.
   2. Maintenance Cost: Water leakage from a sprinkler system caused by the inadequate repair of components defeats the purpose of saving water.
4. Knowledge gap (Transfer of technology from Lab to Land is poor
5. Not fit for all areas: Ill-conceived, not holistic, and disintegrated from the basin/watershed perspective.
6. Energy crisis of India: It requires pressure for water delivery in delivery lines.
7. “Per Drop More Crop” fallacy: If surface irrigation is used scientifically (Not Flooding); It would be cheaper and not that inefficient.

Steps Taken for the Promotion of Micro Irrigation

• National Mission for Sustainable Agriculture (NMSA) – On-farm water management component which focuses on the promotion of efficient technologies and water use efficiency
• PER CROP MORE DROP – PM Krishi Sinchayi Yojana – enhancing WATER USE EFFICIENCY through SUBSIDY for DRIP and SPRINKLER irrigation

Water Conservation Methods:

Watershed Management

A Watershed is a natural geo-hydrological unit that collects rainwater, snowmelt and runoff, and drains it through a system of streams.

Watershed management includes conservation, regeneration and judicious use of all resources – natural (land, water, plants and animals) and human society.

GOVERNMENT INITIATIVES

1. Integrated Watershed Development Program (IWDP) 1990
2. National Watershed Development Program for Rainfed Areas (NWDPRA)
3. Neeranchal National Watershed Project (NWP)

BENEFITS

1. Human Health– safe drinking water, provides food, enables us to adapt to the impacts of climate change more easily by cooling the air and absorbing greenhouse gas emissions
2. Ecological Health– conserves water, promotes streamflow, supports sustainable streams, rivers, lakes, and groundwater sources, enables healthy soil for crops and livestock, and also provides habitat for wildlife and plants.
3. Economic Health– produces energy and supplies water for agriculture, industry and households. Forests and wetlands help to prevent or reduce costly climate change and flooding impacts, manage drought, and contribute to tourism, fisheries, forestry, agriculture and mining industries.
4. Agriculture Health – a lifeline for dryland agriculture, reduces surface runoff of rainwater, increasing recharge of ground water, decentralization of Irrigation – locally ‘AtmaNirbhar’

Decentralized Irrigation

Decentralised irrigation refers to small-scale, storage and distribution of water for agricultural and other needs. It does not involve large-scale dams and canal systems but small-scale structures such as:

1. Rainwater harvesting for water collection
2. Farm Ponds and weirs for storage
3. Drip Irrigation and Sprinkler Irrigation for water delivery

Advantages Of Decentralization

1. Fewer Disputes for the distribution of water owing to the use of local resources
2. 4% vs 80% Gap reduction– India has the world’s 4% water resources but its agriculture sector consumes 80% of water.
3. Reach to unreached – Centralized supply systems are not feasible due to technical, economic or institutional reasons
4. Economical– Small water bodies (mainly tanks) are less capital-intensive
5. Environment – fewer environmental problems and augment groundwater resources through sub-surface recharge
6. Independent from an institutional set-up or centralized systems
7. Promotes on-site modern technologies– Availability of local source of water promotes Drip irrigation, Sprinkler technique

Government Initiative:

• PM-KUSUM – Solar Powered Pumps
• Mission Kakatiyain Telangana government – restoring minor irrigation sources like ponds and tanks. During the Kakatiya dynasty (13th century) thousands of large tanks with sluice-weir devices were constructed to boost crop production.
• Jal Shakti Abhiyan – rainwater harvesting, rejuvenation of waterbodies, reuse of treated wastewater, and intensive afforestation
• PM Krishi Sinchayi Yojana
• Source Augmentation and restoring water body – JAL JEEVAN MISSION, JAL SHAKTI ABHIYAN, Watershed Management.

Participatory Irrigation Management

Pani Panchayats Act (2002) in Odisha allows farmers to govern irrigation systems to ensure equitable distribution of water. Such participatory management of water can be introduced at the national level.

Advantages of Participatory management

1. Sense of Ownership – among the users to promote the economy in water use and preservation of the
2. Better Service Delivery through better operation and maintenance of irrigation systems
3. Optimum Utilization of available resources, precisely as per crop needs
4. Equity in water distribution
5. Balanced Utilization – Increasing production per unit of water where water is scarce and increasing production per unit of land where water is adequate

Constraints

1. Lack of legal backup and policy changes
2. Operation and Maintenance – deterioration of old structure, leakages and seepage at various places, erosion of banks and beds
3. Uncertainty of Water Availability– Farmers are reluctant to take on responsibility for managing the system unless deliveries of water are made reliable, flexible, practical and responsive to need
4. Fear of Financial Viabilityfor Farmers
5. Demographic Diversity– variation in economic, ethnic, and education levels of farmers
6. Need For Monitoring

Way Forward: A Model Policy or law suited to local areas to minimize disputes can be introduced by the central government which can be adopted by the states.

Agronomic Measures to Reduce Water Demand

1. Rainwater harvesting
2. Mulching
3. R&D – Developing & Cultivating Water stress varieties
4. Conservation Tillage
5. Strip cropping
6. Cover crops
7. Organic Farming
8. Agroforestry
9. Better Cropping Practices

Pradhan Mantri Krishi Sinchai Yojana (PMKSY):

It has been conceived as amalgamating ongoing schemes:

1. Accelerated Irrigation Benefit Programme(AIBP), 1996 of Ministry of Water Resources, River Development & Ganga Rejuvenation (MoWR,RD&GR),
   • Aim: to accelerate implementation(central assistance) of such projects which were beyond the resource capability of the States or were in an advanced stage of completion.
   • Priority is given to those projects that were already started and to those that were benefiting Tribal and Drought Prone Areas.
   • 1999-2000 onwards: Central Loan Assistance under AIBP was also extended to minor surface irrigation projects (SMI) of special category States.
2. Integrated Watershed Management Programme (IWMP) of Department of Land Resources (DoLR), Min. of Rural Development.
   • Aim: to ecological balance by harnessing, conserving and developing degraded natural resources such as soil, vegetative cover and water.
3. On Farm Water Management (OFWM) of Department of Agriculture and Cooperation (DAC) & Farmer welfare, Min. of Agriculture & Farmer welfare.
   • Remember – the National Watershed management project for rainfed areas is a different project under MoA

PMKSY initially had a sunset clause of 2019-20. It has not been extended till 2025-26

Objectives of PMKSY:

1. AIBP/investment component: to achieve convergence of investments in irrigation at the field level,
2. Har Khet ko pani(HKKP) component: enhance the physical access of water on farms expand cultivable area under “assured” irrigation,
3. Per drop More crop(PDMC): improve on-farm water use efficiency to reduce wastage of water and enhance the adoption of precision irrigation and other water-saving technologies. Multiple Efforts under it:
   • Atal Bhujal Yojana (ABHY): A scheme launched in 2019 to improve groundwater management services in India.
   • Namami Gange Districts,
   • Pradhan Mantri Kisan Urja Surakshaevem Utthan Mahabhiyan (PM-KUSUM),
   • Water Harvesting Structures through the Watershed Development component of PMKSY to propagate micro irrigation.
   • Micro Irrigation Fund (MIF) with a corpus of Rs. 5,000 crores has been created under
4. Aquifers: enhance recharge of aquifers & introduce sustainable water conservation practices.
5. Watershed management: ensure integrated development of rainfed areas using the watershed approach towards soil & water conservation, regeneration of groundwater, arresting runoff, providing livelihood options & other NRM activities.
6. Water harvesting: water management, crop alignment for farmers & grass root level field functionaries.
7. Water treatment & usage: explore the feasibility of reusing treated municipal water for peri-urban agriculture.

Implementation Ministry/Funding mechanism:

Ministry of Water Resources (M/o WR, RD &GR) heads two of its main components:

1. AIBP: Major & Medium irrigation/multipurpose irrigation projects.
2. PMKSY-HKKP component – which undersees the following projects.
   1. Repair, renovation & Restoration of water bodies,
   2. Surface minor irrigation projects,
   3. Command area development and water management (CAD&WM, 1974 scheme) projects;

Centre: State = 50:50; [For CAD&WM scheme only, other scheme other formula]

• Except for state-sponsored software components such as training of farmers & field functionaries & officials, adaptive trials & demonstrations, seminars/ conferences etc… = 75:25. Special category states: 90:10
• One-time functional grants to farmers @₹1200/hectare;
  45:45:10 = Centre: State: farmer

Long Term Irrigation Fund (LTIF), announced in 2016 budget with a corpus of ₹20,000Cr operationalized, after an agreement b/w:

• MoWR, RD &GR
• NABARD

Planning structure:

To adopt a ‘decentralized State level planning and projected execution’ structure that will allow States to draw up their irrigation development plans based on:

1. District Irrigation Plan (DIP)
2. State Irrigation Plan (SIP).

The state Chief secretary is vested with the authority to oversee the implementation fo the sanctioned projects.

National Water Development Agency (NWDA), 1982:

• NWDA implements the projects. It is a registered Society under the Societies Registration Act, 1860 under the MoWR, RD &GR. Fully funded by GoI, by grant-in-aid.
• Objective: to study the feasibility of the links under the peninsular component of the National Perspective Plan. Subsequently in 1990-91, NWDA Society resolved to take up the studies of the Himalayan Component also.

Way Forward

• Better CROP PRACTICES
  1. Less Water – SYSTEM of RICE INTENSIFICATION and DIRECTLY SEEDED RICE
  2. Rice and Sugarcane to MILLETS

• Rejuvenation of TRADITIONAL STORAGE SYSTEMS
  1. Khadins, Tankas, and Stepwells in Rajasthan
  2. Kulhs in Himachal Pradesh
  3. Temple Tanks in South India
• RECYCLED water used for IRRIGATION
• RIVER INTERLINKING – Water surplus to Water deficit
  1. POLAVARAM PROJECT in ANDHRA – Krishna Godavari inter-basin transfer
• REHABILITATION and DREDGING of DAMS – WATER SECURITY
• Reviving wetlands canals and artificial lakes
• Policy Shift
  1. From water-intensive sugarcane, paddy, cotton, banana etc., to less water-intensive but high-value crops such as pulses, millets, vegetables, legumes, oilseeds, medicinal plants etc.,
  2. Power subsidy needs to be replaced by DBT so that power use can be fully costed.
  3. Assured Prices for MILLETS
  4. Rational Subsidies: The Punjab government, along with the World Bank and J-PAL, has started some pilots with an innovative policy of “Paani Bachao Paise Kamao” to encourage rational use of water among farmers. Under the initiative, meters are installed on farmers’ pumps, and if they save water/power compared to what they have been using (taken as entitlements) they get paid for those savings — this is credited directly into their bank accounts.
• Promoting DRYLAND AGRICULTURE (cultivation of crops entirely under natural rainfall without irrigation) in RAINFED areas – coarse grain, oilseeds, pulses, raw cotton
• Water conservation – Increased SUPPLY

Solving Energy Crisis: Captive solar plants can replace grid electricity or function in tandem during power outages in the short term or at least till such time India’s energy crisis is overcome in future.

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