Wetlands Function Assessment Project

Frequently Asked Questions

Q. What was the Washington State Wetland Function Assessment Project (WFAP)?

A. The project was a statewide effort to develop relatively rapid, scientifically valid methods of assessing how well wetlands perform functions such as improving water quality, reducing floods, and providing wildlife habitat. Methods were developed for depressional wetlands in the Columbia Basin of Eastern Washington and riverine and depressional wetlands in the Lowlands of Western Washington.  Additional methods for other wetland types in Washington State may be developed pending future funding. 

Q. Who was responsible for the project? Who was involved?

A. The project was initially funded by the Environmental Protection Agency and was coordinated by the Washington Department of Ecology. It involved people from local, state, and federal agencies, and the private sector who developed the methods, with the participation of interested parties and the public. Specifically, the development of the existing methods was guided by two technical committees and a policy board. One technical committee oversaw the technical aspects of the project as a whole, while the other addressed technical issues specific to eastern and western Washington. The Interagency Wetlands Review Board and invited guests addressed policy issues. Interdisciplinary teams of regional experts (called Assessment Teams) crafted the methods, which technical experts and the general public then reviewed.

Q. What is a wetland function assessment?

A. A wetland function assessment is a set of procedures that identifies the functions being performed in a wetland, usually by determining the presence of certain wetland characteristics, and determines how well the wetland is performing those functions. Some methods are quantitative, while others are more qualitative.

Q. How are wetland function assessments used?

A. The information from wetland function assessments is used by the private and public sectors to make management decisions about wetlands. For example:

  • They are used to evaluate the wetland impacts of a proposed project and to help determine whether the project can be permitted
  • When wetlands are unavoidably altered, function assessments identify what functions need to be replaced
  • They are used to determine the effects of agricultural activities on wetlands
  • When wetlands are created, function assessments can measure if they are successfully providing the functions for which they were designed
  • When wetlands are restored, they offer a way to measure functions before and after restoration to see what benefits have occurred.

Q. Why was this project needed?

A. The function assessment methods that were available at the time of the project varied in their accuracy and complexity, and did not differentiate adequately between levels of performance. We needed methods that quantitatively describe how well a function is performed and that are specifically designed for the wetland types of the Pacific Northwest.

Q. Do the methods address wetland values?

A. No. While wetland functions and values have been mixed together in previous methods, this project kept the two separated. Wetland functions refer to the biological, chemical and physical processes that wetlands perform, such as storing flood waters, removing nutrients or providing waterfowl habitat. Wetland values refer to how much society, or a specific community, decides a wetland or a particular function is "worth." For example, two different wetlands located in two different areas of the state may provide the same level of floodwater storage.

In one case, the local community may decide that this function is very important to them and decide to stringently protect that wetland. In another community, floodwater storage may not be as important and the wetland may receive less protection. In each case the wetlands are performing the same function, but the wetlands are being valued differently. The methods developed under this project only tell how well a wetland is performing a given function. It is then up to a community or agency to decide how much to "value" that function.

Q. Why did we need new methods when we have the 1987 wetlands delineation manual and regional supplements?

A. Wetland function assessment is different from wetland delineation. A delineation tell us where the wetland is; a function assessment tells us what a wetland does. A delineation does not provide any information on the functions a wetlands performs - it only gives us a wetland boundary. To determine what functions a wetland performs, and how well it performs them, some type of function assessment procedure or best professional judgment must be applied.

Q. Do the wetland function assessment methods change the way wetlands are regulated?

A. Yes and no; the methods are technical tools for use within existing management and regulatory frameworks, and do not change wetlands regulations or policies. However, the function assessment methods provide greater objectivity, detailed documentation and reproducibility. Better information may change the decisions made while implementing regulations. Decisions may be commensurate with level of function and thus, reduce permit review time and save project applicants money.

Q. What approach was used to develop the function assessment methods?

A. The methods use a modified version of the Hydrogeomorphic (HGM) Approach. The HGM Approach is being implemented on a national level by federal agencies. The intent of the HGM Approach is to produce regional methods for different wetland types. It includes a classification system, a process and technical assumptions to use for developing methods, and produces methods that score how well a wetland performs each function. It offers enough flexibility in design of the methods to meet our needs in Washington.

Q. What are the products?

A. The Project has developed two sets of methods.  One for assessing functions in Riverine and Depressional wetlands located in the lowlands of western Washington. The other for assessing functions in Depressional wetlands located in the Columbia Basin of eastern Washington.  These methods are available in two-volume sets that include associated CDs with Excel spreadsheets that can be used to calculate the numeric results.  They can be downloaded or purchased. Additional methods for other wetland types in Washington State may be developed pending future funding. 

Q. Where and when can I receive training on the methods?

A.  There are currently no plans to offer training on the methods.  If and when funding and staff are available to conduct training, announcements will be posted on this web page and sent to Ecology's wetlands email listserv.

Q. How can I get updates on the methods?

A.  Ecology maintains a Wetlands Listserv.  Any future information about the methods will be sent to Ecology's wetlands email listserv.

Q. What is the current applicability of the methods?

A. Ecology highly recommends that those who apply the methods only do so after attending a five-day training session. Training is important to properly interpret and apply the methods, especially when collecting data in the field. Training is also important so results are accurate, consistent, and reproducible. Ecology has been unable to offer training on the methods in over ten years and does not have plans to offer training in the foreseeable future, therefore Ecology can no longer support its use to assess functions of wetlands. The documents will remain on the project web page for historical reference to those wishing to explore the scientific basis for the wetland rating system, which is the current tool for gathering general information on functions provided by wetlands.

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