141-089-0790 Waterway Habitat Improvement – Authorized Projects Project activities are limited to the following. The activities may be combined for a project and the removal-fill volume thresholds for each activity may be calculated separately: (1) Barrier Removal. Barriers may be removed to reconnect or improve waterway corridors, reconnect existing side channel or alcove habitat, reestablish or improve wetlands, restore or improve natural channel and flow conditions, and assist fish and wildlife movement. The project must meet the following criteria: (a) Removal is limited to artificially created barriers including, but not limited to culverts, dams, earthen embankments, bridge abutments, spillway systems, tidegates, outfalls, and pipes; (b) Side channels or alcoves being reconnected must be naturally formed and not require alteration or reconstruction, and the reconnection cannot result in dewatering mainstem flow (i.e., the mainstem must continue to carry the main flow post-construction; and (c) Cumulative removal-fill volume for this project must not exceed 200 cubic yards. (2) Grade Control. This project includes construction of grade control structures to stabilize channel grade, reduce erosion, reconnect a waterway to the floodplain or reduce channel incision. The project must meet the following criteria: (a) Grade control structures must be constructed of materials that mimic natural substrate found within the system; (b) Grade control structures must be placed diagonally across the channel or in upstream pointing “V” or “U” configurations; (c) Grade control structures must be sized appropriately for the system to prevent creating a fish passage barrier or require maintenance; and (d) The project is limited to 100 cubic yards for every one-half mile of waterway, unless otherwise approved by the Department. (3) Fish and Wildlife Passage. This project includes installation or replacement of fish passage structures including, but not limited to, vertical slot fishways, nature-like fishways and lamprey ramps to aid fish and/or wildlife passage. This project additionally includes replacing, improving, or relocating water diversion structures for the primary purpose of restoring or improving fish passage. The project must meet the following criteria: (a) The project is not otherwise exempt pursuant to OAR 141-085-0530; (b) Passage structures must be sized appropriately for the system yet be stable; and (c) The project is limited to 100 cubic yards for every one-half mile of waterway, unless otherwise approved by the Department. (4) Installation, Maintenance, or Replacement of Fish Screening Structures. The project must meet the following criteria: (a) The project is not otherwise exempt pursuant to OAR 141-085-0530; and (b) Cumulative removal-fill for this project, including return pipe volumes for fish screens, must not exceed 100 cubic yards in waters of this state. (5) Porous Weir. This project includes the construction of a self-sustaining, low-profile structure. A porous weir delays but does not store water. It is used to redirect flow toward the center of the channel, provide energy dissipation, and promote increased sedimentation along banks while allowing fish passage through a porous design. This project includes, but is not limited to, cross vanes and artificial riffles. The project must meet the following criteria: (a) Be placed so scour pools occur in areas where pools would naturally form in a pool and riffle complex; (b) Not result in culvert inlet or outlet scour; (c) Be sized appropriately for the system so as not to require maintenance; (d) Be constructed of materials that mimic natural substrate found within the system; (e) Not exceed 40 percent of the channel cross-section width unless otherwise approved by the Department; and (f) Not exceed 100 cubic yards for every one-half mile of waterway, unless otherwise approved by the Department. (6) Remove, Modify, Repair, or Replace Existing Culverts and Tide Gates for Fish Passage. Tide gate and culvert removal, modification, repair, or replacement that will create or improve fish passage is allowed when: (a) The project is not otherwise exempt pursuant to OAR 141-085-0530; (b) The project may include the incorporation of simulated streambed material and shadow boulders inside and beyond the culvert, as necessary; (c) Any placement of new rock to stabilize culvert inlet and outlet must include planting of native woody vegetation appropriate to the area and at a density consistent with natural stream bank densities in the area, unless otherwise approved by the Department and, (d) The project cannot include channel realignment, other than that necessary when placing a new culvert or tidegate immediately adjacent to the existing culvert or tidegate, and cannot convert bed substrate type. (7) Habitat Logs, Beaver Dam Analogs, and Post-Assisted Log Structures. This project includes construction of low-profile structures within a waterway in a manner designed to mimic the hydrological, geomorphological, and ecological functions of natural beaver dams or otherwise mimic natural wood accumulations. The project must meet the following criteria: (a) Cumulative removal-fill volume may not exceed 100 cubic yards for every one-half mile of waterway unless otherwise approved by the Department; (b) No cabling, wiring, or mortaring of materials or use of steel or treated posts is allowed; (c) Wood posts must be untreated and, to the extent possible, must be driven to a depth of at least 1.5 times the expected scour depth of the waterway and with at least one foot of clear space between posts; (d) Log placements must be consistent with “Guide to Large Wood and Boulder Placements” (ODFW, 2011), except that nonrandom placement of logs is permissible. (e) Beaver dam analogs and post-assisted log structures must be consistent with “Beaver Restoration Guidebook” (USFWS, et al .) and “Low Tech Process-Based Restoration of Riverscapes: Design Manual” (USU Restoration Consortium); (f) Weaves must be sufficiently loose to allow fish passage through the structures while maintaining fish rearing habitat in the delayed water area upstream of the structure; (g) Only river-run gravels or cobbles may be used where rock is necessary to prevent under-scour; (h) Native woody vegetation must be preserved to the maximum extent practicable. When not practicable, woody vegetation must be knocked down to allow resprouting rather than removed; and, (i) No water may be diverted from the waterway for a beneficial use within the area in which flow is delayed or slowed by the project without the appropriate water-use authorization from Oregon Water Resources Department. (8) Engineered Log Jams. The project must meet the following criteria: (a) At a minimum, wood pieces, or their cumulative effect, must be of a size sufficient to withstand 25-year flood event rates of flow; (b) Large wood must be of a species native to the riparian zone within the project area or a reference area unless otherwise approved by the Department; (c) The engineered log jam must not occupy more than 20 percent of the bankfull width; (d) If fastening is necessary, only pinning may be used; and (e) If anchoring is necessary, only rock ballast, untreated posts, stabilizing wood, or key pieces of wood may be used as anchors. (9) Maintenance and Reconstruction of In-Stream Habitat Structures. Removal and fill necessary to maintain or reconstruct the serviceability of existing, man-made in-stream habitat structures not otherwise exempted by OAR 141-085-0534. The terms “maintenance” and “reconstruction” have the same meanings as in OAR 141-085-0510. Statutory/Other Authority: ORS 196.600 - 196.692 & 196.795 - 196.990 Statutes/Other Implemented: ORS 196.600 - 196.692 & 196.795 - 196.990 History: DSL 2-2024, amend filed 05/31/2024, effective 07/01/2024 DSL 27-2018, minor correction filed 01/03/2018, effective 01/03/2018 DSL 3-2012, f. 9-28-12, cert. ef. 9-29-12 DSL 2-2011, f. & cert. ef. 3-1-11