Irrigation development can serve different purposes. For Lao PDR, it mainly targets for rural development on generating income opportunity for local people. In watershed management, irrigation is not only designed for production achievement, it is also used for ecological function maintenance e.g. increasing water availability, maintaining minimum flow at downstream and avoiding negative impact on biodiversity. The development of irrigation schemes is therefore one of the approaches supporting livelihood improvement in the watershed by improving farming systems and generating income opportunities for local people and to reduce shifting cultivation. The introduction of irrigation systems is also to improve the ecological function of the watershed by increasing water availability in the dry season and reducing flood events in the wet season.
The existing irrigation schemes are (mainly paddy fields) limited due to the mountainous area. Most of this area is managed with upland agricultural techniques (shifting cultivation). Based on the results of the satellite image interpretation, only 1,300 ha are currently irrigated. Most irrigation schemes are situated at the lower reaches of the watershed area along the Mekong River which are not serving the poor families in upland areas and do not significantly support maintaining the watershed functions. More than 70% of the current irrigated area is served by pump schemes, which are generally not well operating and maintained, also due to weak water user group structures and limited support from the GoL DAFO extension service.
The need for irrigation development under SUMALOM-Nam Ton Project was included in Project Feasibility Study in 2007. According to these plans, most of these proposed schemes are placed in the lowland and not benefitted to the poor. The concept review for irrigation implementation was carried out during project inception phase by prioritising the scheme development in the upland and befitting to the ethnic poor groups. During SUMALOM project inception phase, 8 priority schemes were selected for extension and/or improvement of which 5 schemes were recommended for further implementation.