Tillage and Puddling
Rice fields with few rat holes or cracks rapidly lose water by seepage and percolation during soaking of field. Shallow soil tillage before land soaking close the cracks and amount of water used in wet land preparation can be reduced by 350 mm.
Thorough puddling results in a good compaction of soil, reduces permeability and percolation rates throughout the crop growing period. The efficacy of puddling in reducing percolation depends on soil properties. Puddling is very effective in clay soil (that form cracks during fallow period) and ineffective in coarse soils (do not have enough fine clay particles). Puddlings is not necessary in heavy clay soils and in such soils, direct dry seedling (without puddling but tilled) with minimum percolation losses can be practiced.
Soil compaction using heavy machinery is another option to decrease soil permeability in sandy soil with loamy sub soils having at least 5% clay. Government support can only make this technology feasible on a large scale as most of the farmers cannot afford to compact their soils by their own.