Water, soil and data

Swaziland project uses GIS to identify farmland suitable for irrigation

Doctor Lukhele

A project in Swaziland uses remote sensing and GIS to identify irrigable farmland. The data are analysed to improve the efficiency of project management processes.

Droughts are frequent in the Lower Usuthu region of Swaziland. The semi-arid climate makes it difficult for smallholder farmers to grow enough food for themselves. Average annual incomes are low – around US$ 100 per person – and earnings are unlikely to increase if farmers rely solely on rainfall to water their crops.

Research in the region, however, suggests that irrigating the land could result in crop yields comparable to those found on nearby commercial farms. For example, several farmers have recently started small-scale irrigation schemes to grow sugar cane, and have managed to obtain good yields (105 tons per hectare).

Based on these findings, Swaziland Water and Agricultural Development Enterprise (SWADE), a local state-owned company, is working with several local and international partners to develop a large-scale irrigation scheme for the area. The main infrastructure, including three dams to store flood flows diverted from the Lower Usuthu River, is being constructed as part of the Lower Usuthu Smallholder Irrigation Project (LUSIP).

The project will initially provide irrigation water to 2600 households, covering 6500 hectares of land. For the first time, farmers in the area will be able to move away from subsistence agriculture and produce cash crops, which could increase their income. The first 800 hectares are now being irrigated, while work to bring the scheme to a further 5000 hectares is underway.

Clear position

Remote sensing and (GIS) have been crucial in the planning and management of the project. The data gathered are used primarily to inform farmers on how to make the best use of the newly irrigated land. The GIS data, for example, are analysed to identify areas which can be irrigated, show soil types and plot existing water sources. The team then visit the farmers to give advice on which crops to grow on the irrigated land, depending on the specific local conditions.

SWADE uses geographically referenced data of the area to produce maps pinpointing the households that need special attention; those with very low incomes or situated on land with especially poor crop yields. They also use the maps to outline current land-ownership patterns and to plot community facilities, such as schools and clinics.

The mapping information helps LUSIP staff to give advice to the traditional land authorities when planning future land use. The data can help them designate grazing and rangeland areas, resettle people onto irrigable land, and develop guidelines for water supply, roads and electricity.

As the project has progressed, the team have been updating the maps and GIS data to keep track of their activities. They now note the exact locations of households on land receiving irrigated water and which have already benefitted from the project’s services, including training and crop advice. Knowing exactly which farmers are participating in the scheme, and who has already been contacted, means managers can monitor progress, plan future activities and avoid duplication or wasting resources by visiting homes not directly affected by the project.

Growth experience

Another important part of LUSIP is to keep the public informed about the project benefits and progress. Face-to-face communication is the main method of informing the people living in the irrigated areas. Staff regularly organise community meetings and visits to traditional leaders and farmers to keep them up to date on the latest project developments, and to give training courses on new farming techniques and irrigation technology.

The project team arrange for farmers to visit other parts of the country to learn methods that might be applicable to the new crops they will grow. LUSIP also has a demonstration plot to display and test the profitability of different crops. A specially developed information centre provides a space for workshops, and gives farmers an opportunity to ask specific questions and receive feedback.
The information given at training courses, workshops and meetings is supported by radio, television and newspaper reports. Radio is a particularly important outlet for the project, with staff regularly taking part in national radio programmes to give farmers updates on new agricultural techniques and market opportunities. The radio reports also inform the wider public about the project and the general benefits of irrigation for the country.

Throughout the project, SWADE has used information management systems to help them refine and record the processes involved in introducing irrigation to the Lower Usuthu area. Keeping accurate records of the methodology will ensure the project can be efficiently replicated in other suitable areas of Swaziland. The organisation also encourages staff working on similar projects throughout Africa to visit LUSIP and share ideas, in the hope that others can learn from their work and develop irrigation elsewhere on the continent.


Doctor Lukhele is chief executive officer of Swaziland Water and Agricultural Development Enterprise ( www.swade.co.sz)


Related resources

The following partner organisations are involved in the Lower Usuthu Smallholder Irrigation Project.

International Fund for Agricultural Development

Komati Basin Water Authority

30 August 2010

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