Safeguarding, strengthening and expanding river protections for nature and people

River protection in the United States remains scant, with just over one-tenth of river length in the contiguous states protected at viable levels, often by land-based protection measures that fail to capture the full diversity of the nation’s river systems. There is an urgent need for policies that safeguard, strengthen and expand freshwater protections to secure rivers that sustain both people and nature.

Messages for policy

• Our assessment (and online tool) enables conservation actors to identify gaps in river protection and use data to equip more effective watershed protection initiatives.

• Federal public lands have an outsized role in protecting rivers nationwide, and multiple-use lands provide a major opportunity to scale protections; weakening or eliminating existing environmental policy mechanisms would undermine these safeguards.

• Individual states can have a larger role in river protection through new or strengthened riparian buffer legislation, administrative rules, or agricultural and forestry best practices.

• Protecting rivers flowing through private lands, such as those offered by easements or land trust acquisitions and/or agreements, is key for drinking water and biodiversity.

• Expanding river-specific protections, such as new federal and state Wild and Scenic Rivers and Outstanding Resource Waters, would ensure effective, durable protection measures tailored to rivers.

• Protected Rivers Index analogues should be developed in other countries to support global assessments.

based on L. Comte et al. Nature Sustainability https://doi.org/10.1038/s41893-025-01693-8 (2026).

The policy problem

Despite recent commitments to protect freshwater ecosystems in the United States, our ability to achieve protection goals to sustain the benefits rivers provide to people and nature is uncertain. A major barrier to action is an incomplete understanding of the status of river protection — most existing assessments measure where rivers overlap with terrestrial protected areas, overlooking the unique needs of fresh waters. Because protection indicators are designed for land rather than water, decision makers lack the data and tools to evaluate and track progress towards stronger, more durable freshwater protections. As momentum builds to meet targets such as conserving 30% of inland waters by 2030, policymakers and practitioners must determine which rivers to prioritize for protection and where to reinforce existing safeguards to ensure healthy rivers in the future.

The findings

America’s rivers are alarmingly under protected. Just over one-tenth (12%) of rivers in the contiguous United States and less than one-fifth (19%) nationwide are currently protected at a level deemed viable, while two-thirds remain entirely unprotected under the mechanisms assessed in this study. Most states have less than 10% of their river length under viable protection, with only four states currently exceeding 30% (Fig. 1). Protection is overwhelmingly driven by land-based mechanisms, which are often spatially misaligned with hotspots of freshwater biodiversity and may inadequately safeguard rivers from upstream threats from dams, urbanization, pollution and other stressors. Protection is also uneven across river types and geographies: intermittent rivers are three times less likely to be protected than perennial rivers, and protected rivers are disproportionately concentrated in high-elevation areas. Two-thirds (64%) of rivers flowing through the most critical drinking water watersheds remain unprotected, and an additional 19% are inadequately protected.

Fig. 1: Extent of river protection in the United States.

The extent of river protection in the United States is summarized by state and presented as the percentage of total river length subject to viable or inadequate protection. ‘Viable’ refers to Comprehensive, Effective or Limited protection classes and ‘Inadequate’ refers to the Inadequate protection class, both defined according to the Protected River Index. The dashed line indicates 30% of total river length.

The study

The Protected Rivers Assessment of the United States compiles a centralized database of regulatory frameworks, conservation policies and management practices across federal, state, local, tribal and private jurisdictions that aim to protect rivers, riparian zones, floodplains and surrounding lands. We evaluated the extent and ecological representativeness (sizes, gradients and hydrologic regimes) of river protection nationwide by developing the Protected River Index; a weighted metric that integrates the strength of protection mechanisms targeting five key ecological attributes essential for the long-term persistence of socio-ecological values in rivers. We assessed the protection status for more than 7 million kilometres of river, comparing water-based and land-based protections, evaluating the level of both local and upstream protections, and highlighting opportunities to prioritize future protections that support freshwater biodiversity, intact habitats and critical human water supplies. This study offers a generalizable, analytical framework for evaluating river protection worldwide.