Or. Admin. Code § 141-089-0810 - Wetland Ecosystem Restoration - Authorized Activities

The following activities are allowed under this general authorization:

(1) Vegetation Management. Ground-altering activities needed to re-establish and maintain native vegetation, such as mechanized land clearing to remove non-native vegetation and disking for seedbed preparation and planting of native wetland species.

(2) Floodplain Contouring. Floodplain contouring of wetland terraces to reconnect a waterway to an adjacent wetland or expand the area of seasonal inundation. This activity does not include modification of a stream channel.

(3) Microtopography Establishment. Grading and contouring to re-establish microtopography (hummocks, minor ridges, very shallow depressions) in areas that have been previously leveled, scalped or otherwise disturbed to eliminate pre-existing microtopography. Activity is limited to six-inch maximum elevation rise or drop.

(4) Macrotopography Establishment. Shallow excavation to create scrapes, basins, meanders and swales that do not exceed two feet in depth from existing or original ground surface and have minimum side slopes of 6:1 or gentler. If shallow excavation is combined with berm construction described in Section 6 of this rule, the maximum depth of inundation must not exceed two feet.

(5) Removal of Materials. Removal of soil or other materials that have been placed in a wetland for the purpose of restoring the natural and/or historical topography.

(6) Low Earthen Berms and Spillways. Construction of low earthen berms and vegetated spillways that impede, contain or direct surface water may be used to extend the area or duration of shallow inundation. The design height of the berms must be no more than 18 inches from the existing ground level and have a maximum top width of four feet, variable slopes at a minimum of 6:1 or gentler on the water side, and maximum slopes of 6:1 on the land side, unless gentler slopes do not result in the conversion of wetland to upland. These structures may be installed to manipulate seasonal water depth, duration and degree of fluctuation that would be characteristic of natural or historical hydrologic conditions and to manage invasive species. When berms are combined with shallow excavation described in Section (4) of this rule, the maximum depth of inundation must not exceed two feet.

(7) Removal of Structures. Removal of diversion structures, water control structures, small (three feet high or less) berms and tidegates, as long as the removal does not cause water to rise or be redirected in such a manner to result in damage to structures or substantial property.

Notes

Or. Admin. Code § 141-089-0810

DSL 2-2011, f. & cert. ef. 3-1-11; DSL 31-2018, minor correction filed 01/03/2018, effective 1/3/2018; DSL 2-2024, amend filed 05/31/2024, effective 7/1/2024

Statutory/Other Authority: ORS 196.600 - 196.692 & 196.795 - 196.990

Statutes/Other Implemented: ORS 196.600 - 196.692 & 196.795 - 196.990