OAR 141-086-0370


“Classification” means the designation of wetlands into hydrogeomorphic classes and subclasses. For example, “riverine” would be one class of wetlands.


“Director” means the Director of the Division of State Lands or the Director’s designee.


“Division” means the Division of State Lands.


“Functional Assessment” means the process by which the capacity of a wetland to perform a certain function or group of functions is measured. Such functions would include but are not limited to: surface water storage, sediment removal, and maintenance of characteristic plant communities.


The “Hydrogeomorphic Method” or “HGM” is a scientific method of wetland classification and functional assessment based on a wetland’s location in the landscape and the sources and duration of water flow. The HGM approach identifies the wetland classes present in each region, defines the functions that each class of wetlands performs, and establishes reference sites to define the range of functioning of each wetland class.


“Outstanding State Wetlands” or “OSWs” are reference standard wetlands identified within each Oregon region.


“Reference Standard Wetlands” are one component of an HGM and, for the purposes of these rules, are those sites that best exhibit the highest sustainable level of functional capacity for the functions performed by the regional wetland class or subclass.


“Region” means an ecosystem-based geographical subdivision of the state, such as the Level III and IV Ecoregions of Oregon (e.g., the Willamette Valley) mapped by the U. S. Environmental Protection Agency.


“Wetlands” means those areas that are inundated or saturated by surface or ground water at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions.
Last Updated

Jun. 8, 2021

Rule 141-086-0370’s source at or​.us