National assessment of river protection in the United States

To address the enduring and deepening crisis facing fresh waters, many nations have recently set bold targets for freshwater protection. However, the lack of comprehensive databases and integrative frameworks hampers a robust evaluation of current freshwater protections and prioritization of future opportunities to meet these goals. This study provides a comprehensive assessment of river protection for the USA by reconciling the disparate array of major federal, state, tribal and private protection mechanisms into a single, multifaceted index. We report that just over one tenth of the river length of the contiguous USA and less than one fifth of rivers nationwide are currently protected at a level deemed viable. Lowland headwater streams and intermittent watercourses are consistently underprotected. Protection is also often spatially misaligned with other conservation objectives, where only a small fraction of watersheds with high biodiversity, habitat intactness and importance to drinking water supply are adequately (30% of river length) protected. Our assessment of river protection highlights the urgency to increase new and fortify existing protections for rivers in the years to come if we are to meet ambitious conservation targets, reverse the curve of biodiversity loss and ensure that healthy rivers benefit everyone.