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Why do the WARPT?

Each step of the WARPT process provides a unique result that addresses one aspect of a comprehensive wetland protection strategy and may also help to meet other community objectives.

For each of these major endpoints, several possible variations are presented that range from simple and low-budget to high-tech and intensive, with greater accuracy of results on the higher budget end.  The WARPT can also be done in stages, using results of earlier stages to sell the need to local officials to complete remaining steps. The information below describes how the results of each step may be used, to help determine which ones are most useful for your community.

Step 1. Update Wetland Maps

The end result of this step is an updated local wetland map. This step is particularly useful for communities whose wetlands maps are outdated or are not very accurate or comprehensive.  Communities that have recently updated wetland maps and whose maps include all wetland types, regardless of size or connection to perennial waters may skip this step and move on to Step 2.  

Why update wetland maps?

  • It is easier to protect wetland resources when you have detailed maps of their locations and types.
  • Provides up-front information or prioritization to inform local plan review and Clean Water Act Section 404 evaluations.

Step 2. Estimate Wetland Loss

This optional step results in an estimate of historic wetland loss through a wetland mapping analysis.

Why estimate wetland loss?

  • This is a good first step towards identifying potential sites for wetland restoration, which may be a goal for communities that have lost a lot of their wetland coverage. The results can be used to help set targets for wetland restoration in terms of acreage and types.
  • Quantifying the extent of wetland loss and estimating the functions and values of these lost wetlands can help to make the case for wetlands protection and restoration to local decision makers.

Step 3. Identify Priority Wetlands

The end result of this step is a map of priority sites for wetland protection and/or restoration. Most communities will need to do this important step, which includes three substeps: 3a) assess wetland functions (desktop), 3b) evaluate vulnerability and 3c) assess wetland functions (field).  It is recommended that, at a minimum, communities complete 3a and 3b. Step 3c can be completed later on as resources permit or it can be integrated into the plan review process as a required element. If you’ve already identified priority wetlands for conservation and/or restoration, you can skip this step and move on to Step 4. 

Why identify priority wetlands?

  • Prioritizing wetlands helps to target limited resources to those sites that are most important for providing the functions/services of interest to the community (e.g., drinking water, recreation, flood control) and are most vulnerable to impacts from development pressure or other planned activities.
  • The resulting map of priority sites can be used in a number of ways:
    • Determine wetland areas to include in sending zones for a transfer of development rights program or target areas for purchase of development rights or conservations easement program.
    • Include wetlands important for flood protection in community floodplain program.
    • Incorporate priority wetlands into wetland protection ordinance or zoning, and conservation planning for the community and/or watershed.
    • Provides a ready list of wetland sites to include as part of a wetland banking program.
    • Provide this map to state and federal agencies as an information tool in making jurisdictional determinations that require information on wetland functions.
    • Provides a ready list of sites as part of an off-site mitigation program for stormwater or wetlands/streams and for wetland restoration projects.
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Step 4. Estimate Wetland Values

The end result of this step is an estimate of values provided by wetlands in your community. If the public is not convinced that wetlands have value, and dollar signs are what sways your local decisions makers to make changes, this step may be helpful in your community. An initial estimate can be derived using data from existing studies to make the case for doing the complete WARPT process. A more detailed economic analysis of wetland values is more costly and time consuming but the data generated can then be used to make an informed decision regarding the future use of individual wetlands based on the true costs and benefits of proposed development versus resource conservation.

Why estimate wetland values?

  • Placing a dollar value on the wetland benefits that could potentially be lost with future wetland impacts helps to make the case for wetlands protection and restoration.

Step 5. Protect Wetlands

The end result of this step is a plan for protecting wetlands locally using regulatory or voluntary measures. This is the most important step of the WARPT! Even if your state or municipality already has a regulation that protects wetlands, it may not fully protect your community’s priority wetlands from all impacts.  A combination of regulatory and voluntary measures to protect wetlands from direct and indirect impacts is usually most effective. Decisions about which techniques to use will be based on the existing local programs and regulations, political climate and available resources. 

 

Why protect wetlands?

  • Wetlands provide important services to communities such as flood storage, maintenance of water quality, erosion control, and recreation and educational opportunities.
  • Wetland protection at the local level is important because that is where land use decisions are made.
 
Digitize
The process of converting features on a paper map into digital format using a trace methodology, which results in the creation of a spatial dataset.
Ecotone

A transition area between two adjacent, but different plant communities.

Indirect Wetland Impacts
Impact to wetlands caused by inputs of stormwater and pollutants generated by land development or other activities within the wetland CDA.
Direct Wetland Impacts
Wetland loss or degradation resulting from activities that occur within wetlands, such as dredging, filling and draining.  Activities that cause direct impacts are largely regulated through the federal and state wetland permitting process.
Stormwater Treatment Practices

A structural or non-structural practice designed to temporarily store or treat stormwater runoff in order to mitigate flooding, reduce pollution, and provide other amenities (also called a Best Management Practice – BMP).

Hydrogeomorphic
Factors that influence how wetlands function, including geomorphic setting, water source, and hydrodynamics.
Hydrogeomorphic
Factors that influence how wetlands function, including geomorphic setting, water source, and hydrodynamics.
Sinks
A cell or set of spatially connected cells that cannot be assigned flow direction in a raster elevation dataset. This can occur when all neighboring cells are higher than the processing cell or when two cells flow into one another. Sinks can indicate areas where water is likely to pond, but can also be an error in the dataset.
Facultative Wetland Plants
Species that usually occur in wetlands (approximately 67% - 99% probability), but also occur in non-wetland areas (approximately 1% - 33% probability).
Obligate Wetland Plants
Species that occur almost always in wetlands under natural conditions (greater than 99% probability), but which may also occur rarely in non-wetlands (less than 1% probability).
Interferometric Synthetic Aperture Radar (IFSAR)
A radar technique that uses two or more synthetic aperture radar (SAR) images to generate surface elevation using differences in the phase of waves returning to the satellite or aircraft.
Interferometric Synthetic Aperture Radar (IFSAR)
A radar technique that uses two or more synthetic aperture radar (SAR) images to generate surface elevation using differences in the phase of waves returning to the satellite or aircraft.
Light Detection and Ranging (LiDAR)

A remote sensing technique that measures properties of pulsed laser light reflected from objects to determine their position, velocity, and other information.

Light Detection and Ranging (LiDAR)

A remote sensing technique that measures properties of pulsed laser light reflected from objects to determine their position, velocity, and other information.

Light Detection and Ranging (LiDAR)

A remote sensing technique that measures properties of pulsed laser light reflected from objects to determine their position, velocity, and other information.

Digital Elevation Model (DEM)
A digital file consisting of terrain elevations for ground positions at regularly spaced horizontal intervals.
Digital Elevation Model (DEM)
A digital file consisting of terrain elevations for ground positions at regularly spaced horizontal intervals.
Hyperspectral Data

Information collected and processed from across the electromagnetic spectrum. Spectral signatures (unique “fingerprint” left by specific objects) enable identification of materials that make up a scanned object.

Remote Sensing
Gathering and recording information about objects without actual contact through the use of such techniques as photography, infra-red imagery, and radar.
Hydrophytes
A plant that grows wholly or partially submerged in water.
Blackspots
Areas on aerial photos that show up as dark blue, dark grey, or black and are indicative of saturated soil conditions.
Stereoscopic
The ability to see three dimensionally by using two views of a single object from slightly different positions typically through the use of an optical aid known as a stereoscope.
Hydric Soils
Soils that are saturated, flooded, or ponded for a long enough period during the growing season to develop anaerobic conditions in the upper soil horizons.
Hydric Soils
Soils that are saturated, flooded, or ponded for a long enough period during the growing season to develop anaerobic conditions in the upper soil horizons.
Hydric Soils
Soils that are saturated, flooded, or ponded for a long enough period during the growing season to develop anaerobic conditions in the upper soil horizons.
Hydric Soils
Soils that are saturated, flooded, or ponded for a long enough period during the growing season to develop anaerobic conditions in the upper soil horizons.
Hydric Soils
Soils that are saturated, flooded, or ponded for a long enough period during the growing season to develop anaerobic conditions in the upper soil horizons.
Hydric Soils
Soils that are saturated, flooded, or ponded for a long enough period during the growing season to develop anaerobic conditions in the upper soil horizons.
Hydric Soils
Soils that are saturated, flooded, or ponded for a long enough period during the growing season to develop anaerobic conditions in the upper soil horizons.
Hydric Soils
Soils that are saturated, flooded, or ponded for a long enough period during the growing season to develop anaerobic conditions in the upper soil horizons.
Geographic Information Systems (GIS)

A system that integrates hardware, software, and data for capturing, managing, analyzing, and displaying all forms of geographically referenced information.

Geographic Information Systems (GIS)

A system that integrates hardware, software, and data for capturing, managing, analyzing, and displaying all forms of geographically referenced information.

Digitize
The process of converting features on a paper map into digital format using a trace methodology, which results in the creation of a spatial dataset.
Minimum Mapping Unit

The minimum size or dimensions for features to be mapped as lines or areas for a given map scale.