Strategic restoration-development mitigates tradeoffs between hydropower and fish habitat fragmentation in the Mekong

One Earth, vol. 7, pp. 1096–1107

Abstract

Hydropower can play an important role in decarbonizing energy systems, but opportunities for future low-impact hydropower are limited by existing dams, which are driving declines in freshwater fish worldwide. How to mitigate past development impacts while enabling low-impact future hydropower expansion remains unclear. Here, we propose a strategic restoration-development paradigm to break unfavorable lock-ins from past hydropower development. For the Lower Mekong River, we demonstrate how strategic multi-objective optimization and habitat fragmentation modeling for 710 fish species can be used to design restoration-development policies. Our results show that a combination of removing high-impact dams, fishways retrofitting, and strategic planning can break locked-in environmental impacts and restore connectivity to a level achievable had strategic planning been adopted before the onset of hydropower deployment. This highlights the essential role of restoration in combination with strategic planning for future sustainable hydropower worldwide.

Authors 2

1. Valerio Barbarossa corresponding Aachen Institute of Environmental Sciences (CML)

   Leiden University · Netherlands Environmental Assessment Agency

   Affiliation as printed

   Institute of Environmental Sciences, Leiden University, Leiden, the Netherlands

   PBL Netherlands Environmental Assessment Agency, the Hague, the Netherlands

2. Rafael Schmitt corresponding

   Stanford University

   Affiliation as printed

   Natural Capital Project, Doerr School of Sustainability, Stanford University, Stanford, CA, USA

   Woods Institute for the Environment, Stanford University, Stanford, CA, USA