The long-term sustainability of proposed or existing hydropower schemes strongly depends on the availability of water resources. Under climate change, long-term water resource availability in the Caribbean is highly uncertain. This study presents an approach for assessing future climate impacts on regional hydropower potential premised on the use of hydrological models and projections from the latest generation of climate models. When the methodology is applied to the Afobaka hydropower scheme in Suriname, the results indicate significant changes in, both, water resources availability and hydropower potential with increasing global temperatures. A decrease of approximately 40% is projected by the end of the century for global temperature increase in the range of 1.5 °C above pre-industrial levels. Under a “business as usual” greenhouse gas emissions pathway, which would lead to global temperatures significantly above 1.5 °C, the impact is more severe, with a projected decrease of up to 80% (65 MW) of the firm power capacity (80 MW) by the end of the century.