Publication Summary

This document is Washington State's official manual for delineating wetlands. Delineation manuals are used to determine the edge of a wetland based on three "parameters:" water, plants, and soil.

This document is Washington State's official manual for delineating wetlands. Delineation manuals are used to determine the edge of a wetland based on three "parameters:" water, plants, and soil.

The purpose of this manual is to provide users with guidelines and methods to determine whether an area is a wetland and to delineate its boundaries for purposes of Section 404 of the federal Clean Water Act, the state Shoreline Management Act, or local regulations adopted under requirements of the Growth Management Act.

For the purposes of this manual, the user is provided with indicators for each parameter (from the field or other data sources) that can be used to determine if a wetland is present, and to delineate its boundaries. The indicators have been developed through the study of wetland characteristics and can be considered accurate if used and interpreted correctly.

This manual also provides the user with methods frequently used to collect, record, and interpret field data. Although the manual will provide the user with good technical information, the accuracy of a delineation is directly dependent upon the education and experience of the user. A good delineator is a person who has extensive field experience, is familiar with wetlands ecology, is knowledgeable of the region in which they are working and exercises sound and unbiased scientific and professional judgment.