An instrument used to improve groundwater management in agriculture through subsidies to improve irrigation efficiency by farmers' investments in better technology. This may imply support to make investments in closed conveyance pipes instead of earth canals that are subject to evaporation, shifting from flood irrigation to drip irrigation and investments in soil levelling, mulching etc. However, such measures will only be effective if farmers, for example, do not at the same time expand their fields or increase their cropping cycles.