Abstract: The delta of the River Senegal was modified substantially by the construction
of the Diama dam in 1986 and the floodplain and estuarine areas on the Mauritanian bank
were affected severely by the absence of floods. In 1994, managed flood releases were
initiated in the Bell basin (4000 ha) of the Diawling National Park, as part of a
rehabilitation effort. The basin was designated as a joint management area between
traditional users and the Park authority and a revised management plan was developed
through a participatory approach based on a topographical, hydro-climatic, ecological
and socio-economic data. Hydraulic modelling was developed as a tool to support stakeholder
negotiations on the desired characteristics of the managed flood releases. Initially, a
water balance model was developed. The data were then integrated into a one-dimensional
hydraulic model, MIKE 11 (DHI, 2000). When associated with a Digital Elevation Model and
a Geographic Information System, (Arc View), the model provided a dynamic description of
floods. Flood extent, water depth and flood duration data were combined with ecological
and socio-economic data. The water requirements of the different stakeholders were
converted to flood scenarios and the benefits and constraints analysed. A consensus
scenario was reached through a participatory process. The volume of flood release
required to restore the delta does not affect hydro-power generation, navigation or
intensive irrigation, for which the dams in the basin were constructed. Hydraulic
modelling provided useful inputs to stakeholder discussions and allows investigation of
untested flood scenarios.
Keywords: wetland restoration, water use conflicts, equity, Senegal River delta, Mauritania,
Diawling National Park |