Strategic planning of hydropower development: balancing benefits and socioenvironmental costs

Hydropower continues to expand globally as the power sector transitions away from carbon-intensive fossil fuels. New dam sites vary widely in the magnitude of their adverse effects on natural ecosystems and human livelihoods. Here, we discuss how strategic planning of hydropower expansion can assist decision makers in comparing the benefits of building dams against their socioenvironmental impacts. Advances in data availability and computational analysis now enable accounting for an increasing array of social and environmental metrics at ever-larger spatial scales. In turn, expanding the spatial scale of planning yields more options in the quest to improve both economic and socioenvironmental outcomes. There remains a pressing need to incorporate climate change into hydropower planning. Ultimately, these innovations in evaluating prospective dam sites should be integrated into strategic planning of the entire energy system to ensure that social and environmental disruption of river systems is minimized.