Human related activities cause variability in climatic conditions at the river basin. Inadequacy to manage uncertainties, projections and scenarios, financial constraints, lack of logical cost sharing in multipurpose capital projects results to climate change problems and related hazards at the river basin.

The study determined the optimal benefits under various objectives in a multi-purpose /multi-objective capital projects using Bayesian and Game theories in order to develop a blueprint for green revolution in the river basin. The data was generated from Bill of Engineering Measurement and Evaluation (BEME) in Anambra-Imo river basin as a case study.

Graphs, chi-square, correlation and regression, and trend in climate variability were used for data analysis. The optimal solution from Bayesian model was N68.

72 billion while Game Theory was N69. 02 billion for the period which was N0.

30 billion higher than result obtained from Bayesian analysis. The work recommended that since climate variability impact on the ecosystem, optimal strategies should incorporate delivering benefits irrespective of climate conditions for the benefits of the communities and the region.

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