Freshwater Resilience

© Shea Grehan/TNC Photo Contest 2019

A New, Comprehensive Resource for Freshwater Conservationists

Freshwater Resilience is the ability of a freshwater system to sustain biodiversity even as it responds to a changing climate. Large, diverse and connected river networks in good ecological condition and with ample, unaltered water are more resilient because they provide many ways for freshwater species to adapt to changing conditions.

The Nature Conservancy’s Center for Resilient Conservation Science engaged 60 colleagues over three years to assess river networks in the conterminous United States (CONUS) for resilience to climate change. The Nature Conservancy’s (TNC’s) Freshwater Resilience Analysis, which is completed for CONUS and underway for Alaska, is designed to assist those working to protect or restore freshwater habitats. The two main products are:

Freshwater Resilience is a map and spatial database that scores every small watershed in CONUS for climate resilience and provides users with the component values that went into calculating resilience. The Freshwater Resilient and Connected Network (FRCN) identifies a representative network of rivers, streams and wetlands that, if conserved, could potentially sustain the freshwater diversity of CONUS under a changing climate.

The FRCN represents the top 35% of rivers for resilience and includes both resilient river networks and near-resilient networks that require reconnection to adjacent habitats or restoration of a key feature, such as their flow regime or water quality. Additionally, all river networks in the FRCN have biodiversity value recognized in a State Wildlife Action Plan, Freshwater Ecoregional plan or similar study.

The maps and component data for both resources can be accessed through the Resilient River Explorer online tool at maps.tnc.org/resilientrivers.