Wetland Tools

Wetland Delineation - establishes the existence (location) and physical limits (size) of a wetland for the purposes of federal, state, and local regulations.

Wetland Rating Systems - categorizes wetlands into four categories based on their sensitivity to disturbance, their rarity, our ability to replace them, and the functions they provide. Some decisions that can be made based on the rating include the width of buffers needed to protect the wetland from adjacent development, the amount of mitigation needed to compensate for impacts to the wetland, and permitted uses in the wetland.

Calculating Credits and Debits for Compensatory Mitigation (the Credit/Debit tool) - a tool for calculating when a proposed wetland mitigation project adequately replaces the functions and values lost when wetlands are impacted.

Best Available Science - a two-volume document on the science  available on wetlands, their functions and management.

Watershed Characterization  - a tool for including watershed condition in the planning process. Watershed characterization information can help identify areas that are more appropriate for wetland restoration and mitigation. Links to examples and guidance are provided.

Change Analysis: Status and Trends -  a method to more accurately map wetlands. The wetland maps will be used as a wetlands status and trends inventory to help determine if the goal of no net loss of wetlands is being achieved in Washington State. You can view the medium-resolution Wetland Inventory Map to look for wetlands in your area.