An environmental assessment was conducted on the Bumbuna Hydroelectric scheme in 1996 which was updated in 2000. Although this included a component looking at the impact on the fish communities in the Rokel/Seli River, the World Bank has posed some further questions on this aspect that require further work. Prior to flooding the region to create a reservoir for the hydroelectric dam, planned for 2007, a revised aquatic biodiversity survey is being conducted during each season in 2006 to establish a baseline study with which to inform the likely impact of the dam.  In particular, the analyses look to address several key issues, including:


  • How species in the Rokel/Seli River compare to others in the country and region
  • The presence of endangered, endemic or rare species
  • Whether the BumbunaFalls pose a true obstacle to upstream faunal migration
  • Whether the fish fauna of the reservoir area different
  • Map critical habitats

The study has been designed to sample the fish an other populations along with the physicochemical properties in the Rokel/Seli River during a 12 month period.  Four field visits have been planned, one in each season to ensure a non-biased sample of migratory fish species is taken. Field site locations have been identified and sampled immediately above and below the Bumbuna Dam, in addition to a wider cross section of the watershed higher upriver and those towards the estuary. A variety of sampling techniques have been employed, including gillnets, beach seining, fish traps and engaging local stakeholders to collect fish at specified locations. Working alongside the Institute of Marine Biology and Oceanography (IMBO), fish samples have been taken to form a new freshwater collection, based at the University of Sierra Leone.

Name of Client

Nippon Koei C. Ltd

Project Dates



Sierra Leone