Water: Healthy Watersheds
Landscape Condition Assessments
Landscape condition assessments examine the condition and configuration of natural land cover in the landscape. The type, quantity, and structure of the natural vegetation within a watershed have important influences on aquatic habitats. Vegetated landscapes cycle nutrients, retain sediments, regulate surface water and ground water hydrology, and provide habitat to terrestrial and riparian species. Riparian forests regulate temperature, shading, and organic matter input to streams.
Green infrastructure assessments identify habitat cores or hubs and connecting corridors in the landscape. These assessments are useful in protecting key natural land cover in the landscape that support aquatic ecosystems. Many aquatic organisms depend on being able to move through connected systems to habitats in response to variable environmental conditions. Forested riparian zones are often some of the best remaining green infrastructure links, or corridors, for connecting hubs on the landscape. Lateral connectivity (e.g., a river channel's connection with its floodplain) is also important because it provides critical habitats for fish spawning and feeding, as well as macroinvertebrates, amphibians, birds, and mammals.
The condition of natural land cover is dependent on natural disturbance regimes such as fire. This is particularly important in some regions of the U.S. Natural fire regimes help remove the natural build-up of organic matter, including nutrients that might otherwise be transported to aquatic ecosystems through runoff.
On this page:
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National Ecological Framework (PDF) (2 pp, 1.7MB)
The National Ecological Framework is a geographical information system (GIS) based model of the connectivity of natural landscapes in the lower 48 United States. It was developed to guide the protection of the natural ecosystem processes that give us clean air, pure water, and protected lands that are part of EPA’s mission to protect. The National Ecological Framework follows a hub/corridor approach, delineating large patches of ecologically significant areas as ecological hubs based on data depicting the location of headwater watersheds, forest and wetland patches, and protected lands. Land cover between hubs was analyzed to map corridors as the least-disturbed pathways between hubs. Potential uses of the National Ecological Framework include highway and residential development planning to minimize disturbance, wetland mitigation to maximize landscape connectivity, and designation of greenways to maintain existing connections.
The Nature Conservancy's Active River Area (PDF) (64 pp, 4.49MB)
The active river area framework offers a more holistic vision of a river than solely considering the river channel as it exists in one place at one particular point in time. The active river area represents the lands that contain both aquatic and riparian habitats and those that contain processes that interact with and contribute to a stream or river channel over time. Mapping the active river area, including intact headwaters and the largest intact riparian areas, provides a way to assess the aquatic component of green infrastructure.
Interagency Fire Regime Condition Class Guidebook
The Fire Regime Condition Class (FRCC) Guidebook provides step-by-step instructions for conducting assessments with the FRCC Standard Landscape Worksheet Method, and provides an overview of the FRCC Mapping Tool GIS software used for the Standard Landscape Mapping Method. The information presented in this guidebook aids land managers in assessing the degree to which forest stand management has departed from the natural fire regime.
Southeastern Ecological Framework Project
The EPA Southeastern U.S. Ecological Framework Project uses landscape ecology principles and a GIS based model to identify ecological significant areas and connectivity. The resulting ecological network is intended to be used by states and local communities to guide decisions on protecting important natural areas and ecological systems and their connecting corridors.
Chesapeake Ecological Network Model
The Ecological Network Model aims to identify the most important remaining habitats in the Virginia, Maryland, Pennsylvania, West Virginia, Delaware, and D.C. portions of the Chesapeake Bay Watershed. The model applies a hubs and corridors approach that is based on principles of landscape ecology and conservation biology, which emphasize size and connectivity as essential components of high integrity habitat.
Natural Connections: Green Infrastructure in Wisconsin, Illinois, and Indiana
This website provides maps and GIS data layers for users to make their own explorations of Green Infrastructure in the 4-county region. The maps can be used as a tool for creating linkages between existing protected lands and for identifying opportunities for natural resource protection and restoration. The assessment and maps show that the region has vast green infrastructure resources, but only a limited amount is currently protected and many of the protected areas are isolated from each other.
Maryland Green Infrastructure Assessment
This tool identifies and helps in prioritizing areas within the state that have the greatest ecological importance through identifying large contiguous blocks of natural lands (hubs) and interconnected corridors. The tool also identifies areas that are at a high risk for loss due to urban and rural development.
Virginia Natural Landscape Assessment
The Virginia Natural Landscape Assessment applies landscape-scale geospatial analysis for identifying, prioritizing, and linking natural lands in Virginia. Using land cover data, patches of natural land are mapped and scored according to size, connectivity, biological diversity, and other characteristics that describe ecological integrity. High scoring ecological cores can be designated as high-priority targets for protection activities such as conservation land purchases or easements.
Virginia's Watershed Integrity Model
The Virginia Watershed Integrity Model was developed to show the relative value of land as it contributes to watershed or water quality integrity. It combines datasets describing landscape condition, biological condition, riparian/wetland habitat extent, topography, and source water protection zones into an overall watershed integrity score for lands throughout the state.
An Ecological Integrity Assessment of the New Jersey Pinelands (PDF) (180 pp, 26.23MB)
The Ecological Integrity Assessment of the New Jersey Pinelands evaluated landscape, aquatic, and wetland integrity by examining the extent and arrangement of natural land cover in the landscape and in the drainage areas for aquatic ecosystems and wetland ecosystems. A moving-window analysis was implemented in a geographic information system to conduct the assessments and characterize ecological integrity in 10-meter units across the landscape. The results of the assessment are used in a land-use-management program that directs development away from areas considered ecologically critical to areas deemed less critical.
BioMap2: Conserving the Biodiversity of Massachusetts in a Changing World
BioMap2 is designed to guide strategic biodiversity conservation in Massachusetts over the next decade by focusing land protection and stewardship on the areas that are most critical for ensuring the long-term persistence of rare and other native species and their habitats, exemplary natural communities, and a diversity of ecosystems. BioMap2 identifies core forest, wetland, and aquatic habitats that are critical for protecting rare, threatened, and endangered species. In addition, it identifies critical natural landscapes that provide habitat for wide-ranging native species. The assessment is based on the principles of landscape ecology and ecosystem resilience, and makes use of sophisticated geographic information system methods to model ecological integrity across the landscape.
North Carolina Open Space and Conservation Lands Assessment
The North Carolina Conservation Planning Tool was developed to streamline the process of identifying and prioritizing areas in North Carolina’s landscape that are essential for conservation. The selected planning approach is based on green infrastructure principles that emphasize the importance of maintaining an interconnected network of green space that conserves valuable natural ecosystem functions, while also providing associated benefits to human populations. The tool uses GIS map layers describing biodiversity and wildlife habitat, open space and conservation lands, water services, agriculture lands, forestry lands, and marine and estuarine resources to grade the ecological significance of an area. It pinpoints areas that are already protected as well as those areas in the landscape that represent protection gaps in a functional ecosystem network.
Minnesota Terrestrial Habitat Connectivity Assessment
As part of its integrated assessment of watershed health, the Minnesota Department of Natural Resources mapped terrestrial habitat patches for representative wildlife species using land cover data and habitat models. A second model was then applied to map connectors between habitat patches throughout the state. Results were used to score terrestrial connectivity within Minnesota’s watersheds, with high scoring watersheds containing large patches of forest, grassland, and wetland habitat and connections linking these habitat patches.
Closing The Gaps in Florida's Wildlife Habitat Conservation System (PDF) (246 pp, 21.4MB)
Identifies a statewide system of landscape hubs and conservation corridors to conserve critical elements of Florida's native ecosystems and maintain connectivity among ecological systems and processes.
Cecil County, Maryland Green Infrastructure Plan (PDF) (51 pp, 3.88MB)
The Conservation Fund completed a Green Infrastructure Plan for Cecil County, Maryland, which includes four key components: 1) a green infrastructure network design; 2) water quality maintenance and environmental analysis; 3) ecosystem services assessment; and 4) implementation quilt analysis. Taken together, this set of products outlines a comprehensive approach to green infrastructure protection in Cecil County.
Anne Arundel County Greenways Master Plan
In an effort to protect its ecological, aesthetic, and cultural resources from fragmentation due to scattered development, Anne Arundel County assessed its existing greenways and areas that have the potential to become part of a greenways network to prioritize them for protection. Five criteria were used to identify 100 areas that form connections between greenway hubs that are critical to ensuring the ability of the greenways network to support crucial ecological functions.
Beaver Creek Green Infrastructure Plan (PDF) (39 pp, 3.9 MB)
The Beaver Creek Watershed Green Infrastructure Plan integrates smart growth and smart conservation concepts to identify lands suitable to serve as conserved riparian buffers, greenway connections, and linkages between neighborhoods and communities within the Beaver Creek Watershed's green infrastructure system.
Green Infrastructure Plan in Hampton Roads, Virginia (PDF) (52 pp, 13.5 MB)
The Commission developed a green infrastructure plan to be used by local and regional planners to ensure that high-priority conservation lands are protected in a multipurpose network. This edition of the plan updates the original green infrastructure network and rates the vulnerability of high-priority conservation lands to the negative impacts of future growth.
Twin Cities Regionally Significant Ecological Areas
The Minnesota Department of Natural Resources conducted a landscape assessment of the Twin Cities metro area to identify ecologically significant terrestrial and wetland areas using data from the Minnesota Land Cover Classification System. The following 6 attributes, based on ecological principles, were used to identify regionally significant terrestrial and wetland areas: natural land cover (low imperviousness area & presence of continuous vegetative cover); patch size; patch shape; adjacent land cover/use; connectivity to other natural areas; and presence of native plant communities. Collectively, the mapped significant ecological areas provide wildlife habitat, maintain biological diversity, maintain connectivity, contribute to groundwater recharge and improved water quality, and represent high to outstanding examples of native plant communities.