Protected Rivers Assessment of the United States (PRA-US) Version 1.2.

Conservation Science Partners, in partnership with American Rivers, has developed the Protected Rivers Assessment of the United States, a data-driven nationwide inventory of present-day river protection status. The Protected Rivers Assessment of the United States (PRA-US) helps conservation practitioners, policymakers, scientists and the public understand the current state of river protection and identify opportunities to expand protection in the future. This assessment leverages a large array of datasets capturing the different mechanisms conferring protection to rivers, including river conservation (e.g., Wild and Scenic River designations, Outstanding National or Tribal Resource Waters), riparian and floodplain conservation (e.g., Riparian National Conservation Areas, Emergency Watershed Protection – Floodplain Easements, Northwest Forest Plan Riparian Reserves), policies focusing on endangered species (Endangered Species Act Critical Habitat), and terrestrial protected areas that incidentally protect rivers (e.g., National Wilderness Preservation System, National Parks, Areas of Critical Environmental Concern). The Protected River Index (PRI) was developed by attributing different weights to each protection mechanism according to their potential conservation of five key ecological attributes that are essential for the long-term persistence of socio-environmental values (hydrologic regime, connectivity, water quality, habitat, biotic composition). Protection classes were then defined according to data ranges (Comprehensive > Effective > Limited > Inadequate > No protection), considering protection to be “viable” if more than one quarter of the key ecological attributes of rivers are intended for protection. The extent of protection was then summarized at the stream segment and watershed scales for each protection mechanism and PRI categories and by considering both local and upstream protection. Finally, a set of variables capturing the values and threats to rivers were summarized to provide contextual information in support of protection prioritization.