The project was first proposed in the 1970s, when a larger dam had been considered. In 1998 the African Development Bank approved funding for a feasibility study that was conducted by the German consulting firm Lahmeyer. Under the study, an environmental and social diagnosis and an initial environmental and social assessment were conducted. The findings were presented in 2002. In August 2002 the government decided by Decree to go ahead with the project, which was from that time called the Kandadji Ecosystems Regeneration and Niger Valley Development Programme. Subsequently, a detailed assessment of environmental and social impact, including a Population Resettlement Plan and a Local Development Plan, was conducted. The Local Development Plan was designed to facilitate the economic transition of displaced persons in order to restore their standard of living or even enhance it, beyond mere resettlement. The final design of the dam was prepared with financing from the
Islamic Development Bank, and that of a irrigation project with financing from the
West African Development Bank. In 2005 and 2006 consultations were undertaken as part of the environmental and social assessment, which included participants from the
World Wide Fund for Nature and
International Union for Conservation of Nature. According to one source, construction of the dam was begun in August 2008. In April 2009 a workshop on benefit sharing from dams in West Africa was held in Niamey organized by the
Niger Basin Authority, the
International Institute for Environment and Development and the
International Union for Conservation of Nature. The workshop recommended to improve the communication towards the people affected by the dam and to pay particular attention to legal processes related to resettlement, and to continue to reflect on a future management structure to equitably share the benefits of the dam. In November 2009 a process to select consultants to accompany the resettlement has been initiated. According to the World Bank, the entire Kandadji Program will be implemented in three phases: • Phase I, which started in 2009 and is expected to be completed in 2016, comprises the Kandadji dam and its reservoir, the hydro-mechanical equipment for the 18 gates, economic and local community development, and implementation of environmental and social mitigation measures for resettled people; • Phase II comprises construction of the hydropower plant, transmission lines, road, irrigated agricultural development, and expanded local and community development in the reservoir area and downstream, and • Phase III focuses on the development of irrigated agriculture and the scaling-up of the economy and local community development of the region (including fisheries, livestock,
agribusiness and trade. Construction of the dam itself was contracted to Russian company
Zarubezhvodstroy, which signed the construction contract in September 2010. The Kandaji Dam is the first object being constructed by a Russian company in Niger. In May 2011, the Director General of Zarubezhvodstroy, OJSC E.V. Gudzenchuk, announced "For the first time a Russian company is involved in building such a large project in West Africa at the expense of foreign investors. Zarubezhvodstroy has vast experience in the field that would allow us to meet the challenges with confidence and with great professionalism." Construction of the dam was begun in August 2008. The first brick of the dam was laid by the President of Niger,
Mamadou Tandja. In 2008, the dam itself was expected to be completed in 2013. Construction has been slower than expected, with interruptions due to financing problems; as of 2019, completion is expected in 2025. Construction works were 12% complete as of September 2019. == Technical features ==