How to do water management in paddy to save water?

Save water in paddy with alternate wetting and drying (AWD) instead of keeping the field flooded all the time. After the first 2 to 3 weeks of crop establishment, let the water drop to about 15 cm below the soil surface using a perforated field water tube, then re-irrigate, except during the sensitive flowering stage when you should keep a thin water layer. AWD can cut water use by 15 to 30 percent with little or no yield loss, and also reduces methane emission and saves pumping cost. Combine with good levelling, bunding to stop seepage, and DSR where suitable. Avoid AWD on very leaky sandy soils.