# Rice and Water Paddy rice is one of the thirstiest field crops, using about 30% of the world's irrigation water; in Punjab it has driven groundwater extraction well beyond recharge, and India's rice exports carried about 40 billion m³ of virtual water abroad in 2023-24. Source page: https://www.materialinsights.org/links/rice-and-water/ [Rice](https://www.materialinsights.org/commodities/rice/) (commodity) and [Water](https://www.materialinsights.org/commodities/water/) (commodity): 5 relationships. ## How they are linked ### 1. Paddy's irrigation demand *Physical flow · Strong · Water → rice* Lowland rice is grown in flooded fields, so it needs far more water per kilogram than most grains, supplied by rain or irrigation. - **about 2,500 litres** water supplied per kg of rough rice, average - **about 30%** rice's share of global irrigation water Much of that water is needed to keep fields flooded rather than taken up by the plant, which is why field practice matters. Alternate wetting and drying, letting fields dry between irrigations, can cut irrigation water use by up to 25% without lowering yields in most regions. Sources: [IRRI, Rice Today](https://ricetoday.irri.org/every-drop-counts/); [IRRI, Rice Today](https://ricetoday.irri.org/alternate-wetting-and-drying-can-help-revolutionize-global-rice-farming/) ### 2. Paddy and Punjab's falling water table *Shared risk · High in India · Rice area growth → groundwater depletion* Punjab's paddy area grew on tube wells running on free or heavily subsidised electricity, so farmers pump more groundwater than rain and canals put back. - **3.06 Mha** Punjab paddy area in 2018, up from 2.18 Mha in 1996 - **about 0.5 m a year** fall in Punjab's post-monsoon water table, 1996 to 2018 - **152%** Punjab groundwater extraction as a share of annual availability, 2025-26 Paddy rose from about 52% to about 74% of Punjab's net sown area over those years, and 110 of the state's 153 assessed blocks are now classed as over-exploited. The pressure is local: rice grown on monsoon rain or canal water elsewhere does not drain aquifers in the same way. Sources: [Down To Earth](https://www.downtoearth.org.in/water/punjabs-groundwater-crisis-52-more-groundwater-extraction-than-annual-availability-canals-being-sought-as-a-solution); [MDPI, Sharma et al.](https://mdpi.com/2071-1050/15/3/2426) ### 3. Rules on when paddy may be planted *Policy · Medium · State law shifts paddy water use towards the monsoon* The Punjab Preservation of Subsoil Water Act 2009 bans paddy nurseries before 10 May and transplanting before 10 June, so that more of the crop's water comes from monsoon rain. - **10 June** earliest paddy transplanting date under the 2009 Act A 2009 study cited in the paper projected that the later date could check the water table fall by about 30 cm and save about 276 million kWh of subsidised power. The Act shifts timing but not the crop's total water need, and free farm power still makes pumping nearly costless for the farmer. Sources: [MDPI, Sharma et al.](https://mdpi.com/2071-1050/15/3/2426) ### 4. Virtual water in rice exports *Physical flow · Strong · Indian water → rice exports* Water used to grow exported rice leaves the country inside the grain, so a large rice exporter is in effect exporting water. - **about 16 Mt** India's rice exports, 2023-24 - **about 40 bn m³** virtual water carried by those exports NCAER puts Punjab's groundwater extraction at 164% of sustainable recharge, a different basis from the state assessment's 152%, but both show extraction well above recharge. Export bans and minimum export prices, used to protect domestic supply, also cut this water outflow. Sources: [Down To Earth](https://www.downtoearth.org.in/water/punjabs-groundwater-crisis-52-more-groundwater-extraction-than-annual-availability-canals-being-sought-as-a-solution); [NCAER (Bose and Pohit)](https://ncaer.org/publication/invisible-drain/) ### 5. Price link: irrigation input *Cost and price · Weak · Both ways* The site's water series is a California water market index and its rice price is the Thai export price, which is set by Asian supply, so the two do not share a price cycle. - **-0.11** monthly change correlation - **-0.39** 12-month change correlation - **-0.06** fitted elasticity The weak, slightly negative figures mean water prices are not a useful guide to rice prices. In India the cost of irrigation water to the farmer is largely hidden by free or subsidised power for pumps, so scarcity shows up in falling water tables rather than in prices. Sources: [MDPI, Sharma et al.](https://mdpi.com/2071-1050/15/3/2426); [Material Insights (World Bank, FRED, IMF data)](https://www.materialinsights.org/commodities/rice/correlation/) ## For investors ### Key learnings 1. Groundwater, more than land, is the long-term constraint on paddy in Punjab, so aquifer trends are a supply risk for Indian rice exports. 2. Water scarcity does not show in rice prices because irrigation is largely unpriced, so price data will not give early warning. 3. Water-saving practices such as alternate wetting and drying, and crop shifts away from paddy, are where policy and spending are likely to go. ### What to track - **Punjab and Haryana stage of groundwater extraction**: Rising values signal tighter future limits on paddy area (Yearly · Central Ground Water Board assessment) - **India rice export volumes and export rules**: Shows how much water leaves in grain and the risk of export curbs (Monthly · DGCIS and Commerce Ministry) ## For policymakers ### Key learnings 1. Free power for tube wells makes groundwater nearly free to paddy farmers, which drives over-extraction in Punjab. 2. Timing rules such as the 10 June transplanting date help but do not change the crop's total water need; crop diversification and water-saving methods address the volume. 3. India's rice exports carried about 40 billion m³ of virtual water in 2023-24, so export policy is also water policy. ### What to track - **Over-exploited groundwater blocks in Punjab**: Measures whether depletion is spreading or easing (Yearly · Central Ground Water Board) - **Paddy area in Punjab and Haryana**: Main driver of groundwater demand in the region (Each season · state agriculture departments) - **Area under alternate wetting and drying or direct seeded rice**: Uptake of water-saving practice (Yearly · state agriculture departments) ## India India shipped about 16 Mt of rice in 2023-24 with about 40 billion m³ of embedded water, while in Punjab paddy covered about three quarters of the net sown area in 2018 and groundwater extraction runs at about 152% of annual availability. ## Sources 1. [Every drop counts](https://ricetoday.irri.org/every-drop-counts/), IRRI, Rice Today (2009) 2. [Alternate wetting and drying can help revolutionize global rice farming](https://ricetoday.irri.org/alternate-wetting-and-drying-can-help-revolutionize-global-rice-farming/), IRRI, Rice Today (2025) 3. [Punjab's groundwater crisis: 52% more groundwater extraction than annual availability](https://www.downtoearth.org.in/water/punjabs-groundwater-crisis-52-more-groundwater-extraction-than-annual-availability-canals-being-sought-as-a-solution), Down To Earth (2026) 4. [Pre and post water level behaviour in Punjab: impact analysis with DiD approach (Sustainability 15(3), 2426)](https://mdpi.com/2071-1050/15/3/2426), MDPI, Sharma et al. (2023) 5. [Invisible drain](https://ncaer.org/publication/invisible-drain/), NCAER (Bose and Pohit) (2026) 6. [Price correlation, Material Insights](https://www.materialinsights.org/commodities/rice/correlation/), Material Insights (World Bank, FRED, IMF data)