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Recovery Potential Screening

Beneficial Uses of Recovery Potential Screening (RPS)

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Supporting Watershed Approaches 

For decades, EPA has made the watershed approach a guiding principle of its programs under the Clean Water Act and Safe Drinking Water Act. Reducing pollution from the watershed (the land area surrounding and draining to a stream, lake or river) has proven to be essential to restoring the great majority of polluted waters, as well as keeping clean waters healthy. The information needed to use watershed approaches, however, was limited for many years and most watershed analysis tools were expensive and complex. Scientific understanding of watershed effects has increased, and more and more national watershed data have now become available. EPA invested in developing Recovery Potential Screening (RPS) tools and assisting their users to help make this knowledge base accessible, efficient and useable by anyone working to restore or protect the nation’s waters. This assistance is helping make watershed approaches and information from local to national scales more accessible than ever before.

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Developing Watershed Analysis Data and Tools 

Not long ago, state and other water quality programs had to choose whether to put their restoration efforts where limited data were available or invest in gathering more data that would support more comprehensive decisions and strategies. The situation improved with the development of better tools and more comprehensive, uniform information. The EPA Office of Water developed RPS as a flexible, user-driven tool to help compare impaired waters more quickly and efficiently and set priorities for investing limited restoration resources. To maximize its user audience, the RPS Tool was developed in commonly used software. The RPS Tool provides embedded watershed data, already transformed into water-quality-relevant indicators in three categories (Ecological, Stressor, Social) from which the user selects the best ones for their purpose and locale. Much of the watershed indicator data used in RPS comes from the Watershed Index Online (WSIO), which houses a national library of hundreds of watershed indicators for the watersheds of the lower 48 states. The partnership of EPA Office of Water, EPA Region 4 and EPA Office of Research and Development that created the WSIO and the RPS Tool has resulted in substantial time savings for water programs, leaving more resources to improve water quality.

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Assisting State Water Program Priorities 

Since 2004, RPS projects have taken place in most of the states and several special project areas (e.g., multi-state river basins) with EPA assistance. Publicly available, state-specific RPS Tools cover all states and US territories. Most of EPA’s support has involved partnering with state water quality programs responsible for listing and tracking impaired waters and developing Total Maximum Daily Loads (TMDLs) restoration and protection program vision priorities. State nonpoint source pollution control programs have also used RPS Tools extensively in statewide runoff control strategies and, in some cases, identifying healthy watersheds for protection. EPA technical assistance with the RPS Tool has also helped many states develop nutrient pollution control strategies. Recently, RPS has played an important role in helping state water programs set long-term priorities for where their greatest efforts toward restoration and protection will take place. 

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Helping Tribes in Watershed Analysis 

Although RPS Tools were developed for individual states, tool usage need not be on a statewide basis. To support tribes, EPA has compiled information on the watersheds that contain tribal lands and those watershed immediately adjacent to tribal lands. Tribal users can select just their own tribal watersheds, and their immediate neighboring watersheds if desired, and comparatively assess them for a given purpose. Results will describe the range of conditions in tribal watersheds alone, but can still be compared easily with statewide results when this may be useful. Special instructions for using the RPS Tool in support of  tribal water quality efforts are available in Watershed Tools for Tribes (PDF)  (2pp, 614K).

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Improving Local Access to Technical Watershed Information 

The RPS approach is also applicable to more local scales such as comparing subwatersheds within a county or river basin. Local-scale efforts to restore and protect the nation’s waters far outnumber efforts at larger scales and often have the advantage of greater local community and stakeholder involvement and insights. Using the RPS Tool in local settings can be a great opportunity to include very specialized local knowledge and create user-defined indicators that can produce better results. All RPS Tools allow for selecting any user-defined subset of watersheds to screen a more localized area, and local data available only for those watersheds can easily be added to the hundreds of indicators already in the RPS Tool. Special instructions for using the RPS Tool in local settings are available in Watershed Tools for Local Scale Projects (PDF)  (4pp, 662K). 

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