Building on a tradition of rainwater harvesting
units. Runoff flows into the 'open end' of the plot and the excess finds its way around the tips
of the arms, higher up the slope. In the case of prolonged standing water, the farmer - or,
more correctly, the agropastoralist merely breaches the bund.
As yet neither of these traditional techniques, from Somalia and Sudan have attracted the
attention they deserve. The same, however, is not true of the stone-bunding technique in
Yatenga Province of Burkina Faso. Here, the traditional system is to use stone lines, or
sometimes stone bunds, across the fields. The Oxfam-supported 'Projet Agro-Forestier' (PAF),
began by attempting to introduce rainwater harvesting for tree planting - but with little
success. The project then realized some years ago that what the villagers really wanted was at
their doorstep. The farmers were interested in improved systems of stone bunding to harvest
water for their crops, and simultaneously to capture sediment for their degraded fields.
Figure 2: The teras system of the Sudan.
PAF showed farmers how to build better bunds. One improvement was to dig a trench of a few
centimetres depth in which the larger 'foundation' stones were sited, then to place smaller
stones in front of this framework. An efficient filter is thus formed. Another technical
innovation was the introduction of the 'contour concept'. Stone bunds work much more
efficiently when aligned along the contour. PAF taught farmers to use simple water levels to
determine the contours for themselves.
The development of appropriate rainwater-harvesting systems depends, however, not only on
the promotion of suitable techniques but also on the way in which community organization is
handled. This successful example from Burkina Faso provides several useful lessons of how to
approach the social as well as the technical issues. Farmer training, for example, - of women
as well as men, has proved to a vital factor in the rapid expansion of stone bunding in the