Enhancing the resilience and productivity of rainfed dominated systems in Lao PDR through sustainable groundwater use

Commissioned Report

Owing to a high prevalence of rural poverty in Lao PDR, improving the livelihoods of smallholder farmers by increasing their productivity is a high priority for the Government. Smallholder farming relies primarily on rainfall, which is prone to shortfalls and occasional droughts during the crop planting season. Reliable irrigation supplies would allow farmers to overcome water deficits and boost crop and livestock production, offering great potential for poverty reduction and increasing food security and livelihoods. Irrigation in Lao PDR has traditionally involved the use of surface water resources. Groundwater could also play an important role for smallholder farmers lacking access to reliable surface water supplies if these resources can be adequately understood and sustainably developed.
Groundwater development and usage in Lao PDR has been unregulated and the weak institutions in place have been unable to implement effective management. Experience in groundwater-based irrigation is almost non-existent in the country. Recent policy initiatives by the Government have bolstered water resources management planning, including consideration of opportunities for groundwater irrigation as an important area for development. With groundwater governance in its early stages, there is a need to build capacity to assess and manage groundwater resources effectively and advance the use of groundwater for agriculture without compromising the users of the groundwater or the resource.
This project has focused on two inter-connected goals: (i) contributing towards the sustainable management of groundwater resources; and (ii) demonstrating the use of groundwater for small-scale irrigation. It naturally also had a strong capacity building and training component.
The project worked from the national scale down to the household scale. At the national level, the potential for groundwater development was mapped, policy analysis was conducted and capacity enhanced through formal training courses and studies linked to the research activities. At the catchment level, groundwater quantity and quality assessments were carried out. Groundwater irrigation demonstration sites were established with the active participation of local communities. Sites were chosen in lowland and upland areas to broadly reflect the different types of groundwater occurrence in the country. The lowland sites included the Vientiane Plain and southern province of Champasak whilst the upland site was in Bolikhamxay Province.
The major findings according to the major components of the project are as follows:
Sustainable management of groundwater resources:
At the national scale, groundwater potential and baseflow maps have been developed and validated using the available data. These maps highlight areas likely to be most suited for resource development. On the Vientiane Plain, studies have been conducted on groundwater recharge estimation at multiple scales, current groundwater use estimation, hydrogeology and flow systems, and soil and water quality. Similar, but less intensive studies have been carried out at the study sites in Bolikhamxay and Champasak provinces. Overall, the understanding of the hydrogeology and groundwater systems has been greatly improved and enabled the areas of fresh groundwater and suitable yield to be more clearly delineated. The data and tools can help guide future development and enable better management of the groundwater resources by government authorities. The local community (farmers, drillers, water user groups, etc.) and the wider community they serve would also benefit.
The alluvial deposits of the Vientiane Plain provide a significant potential resource for groundwater development for improving food production, with recharge rates in excess of 400 mm per annum and current use estimated to be less than 5 percent of the recharge. However careful management of the groundwater resources are required due to the importance of the resource for domestic supplies and the risks from underlying salt-bearing layers. A groundwater model for the Plain has been developed by the Natural Resources and Environment Institute and a Management Plan for the upper Vientiane Plain is under development by the Groundwater Division of the Department of Water Resources.
Use of groundwater for small-scale irrigation:
The first-ever community-managed groundwater irrigation trial has been established at Ekxang village, situated on the Vientiane Plain. Four male farmers have participated in dry season cropping with groundwater. Additional net incomes as high as LAK 4 million (AUD 670) per season were generated by the farmers who chose to grow cash crops and participated effectively. This provides encouragement for wider use of groundwater irrigation. Given the short duration of the evaluation (one dry season) and the limited adoption by farmers in the first year, further research would be beneficial to assess the longer-term uptake, sustainability and how benefits of the system could be maximized. Individual enterprising farmers have been utilising the groundwater resources for production of watermelon, long bean and other crops for the market using simple, low cost technologies. Investment costs for an open dug well, a pump and necessary pipes are as little as LAK 5 million (AUD 840) and can generate net incomes of LAK 20-30 million (AUD 3,400-5,000) per season from one hectare of land. Guidelines to establish groundwater irrigation schemes in Lao PDR are being prepared to help assist prospective implementing agencies.
Capacity building and training
There has also been a strong emphasis on strengthening the technical capacity of staff from government agencies in the water, agriculture and energy sectors and from academia. Over 100 Lao nationals have been trained through short courses, internships, on-the-job training and academic study. There have been around 15 undergraduate and graduate projects by Lao students completed or underway. The first demonstration of groundwater-based irrigation has been established at the NUOL Faculty of Water Resources campus at Tad Thong, which serves as an easily accessible experimental facility for education and training of staff and students testing crop productivity under a range of conditions. The site can also serve to demonstrate groundwater irrigation to prospective farmers and extension staff.
Through these activities the project has made several important achievements:
(i) increased the profile of groundwater to national authorities and raised awareness amongst a broader range of stakeholders;
(ii) provided a basis for improved capacity development within Government and at the National University; and
(iii) contributed to formulation of new national policies, including the National Groundwater Action Plan.

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