OAR 629-625-0320: Water Crossing Structures

(1) Operators shall design and construct all water crossing structures in all typed waters and lakes, bays, ponds, impounding reservoirs, springs, rivers, streams, creeks, estuaries, marshes, wetlands, inlets, and canals to: (a) Minimize excavation of side slopes near the channel. (b) Minimize the volume of material in the fill. (A) Operators shall minimize fill material by restricting the width and height of the fill to the amount needed for safe use of the road by vehicles, and by providing adequate cover over the culvert or other drainage structure. (B) Fills over 15 feet deep contain a large volume of material that can be a considerable risk to downstream beneficial uses if the material moves downstream by water. Consequently, for any fill over 15 feet deep operators shall submit to the State Forester a written plan that describes the fill and drainage structure design. Written plans shall include a design that minimizes the likelihood of: (i) Surface erosion; (ii) Embankment failure; and (iii) Downstream movement of fill material. (C) The operator shall armor fills against erosion where large fills over 15 feet deep are determined to be necessary by the State Forester. (c) Prevent erosion of the fill and channel. (d) Minimize hydrologic connectivity for adjacent roadway. (e) Avoid or minimize alterations or disturbances to stream channel, bed, bank, or bank vegetation to that which is necessary to construct the water crossing structure. Operators shall limit the alteration or disturbance of stream bed, bank, or bank vegetation to that which is necessary to construct the project. (f) Plant disturbed stream banks with native woody species or stabilize with other erosion control techniques. (g) Ensure that streamflow is not likely to be diverted out of its channel if the crossing fails. (h) Preserve water quality and unobstructed flow. (i) Route and deposit temporarily turbid water from crossing projects to the forest floor in an upland area, or above the 100-year flood level if present, to allow removal of fine sediment and other contaminants prior to discharge to waters of the state. (j) When the State Forester determines that installing a water crossing in a flowing stream will cause excessive sedimentation and turbidity, and sedimentation and turbidity would be reduced if stream flow were diverted, operators shall divert stream flow using a bypass flume or culvert, or by pumping the stream flow around the work area. In this situation, operators may install culverts within 0.25 miles of a Type F or Type SSBT stream or within two miles of a hatchery intake. (k) For water crossing structures on Type F and Type SSBT streams, operators shall, consistent with the rules in this section: (A) Avoid or minimize impacts to fish and their spawning and rearing habitat; (B) Minimize the loss of fish life during the project; and (C) Ensure free and unimpeded fish passage at all flows when fish are expected to move through the life of the structure. (2) In selecting a crossing design strategy, operators constructing or reconstructing crossings in all typed waters and lakes, bays, ponds, impounding reservoirs, springs, rivers, streams, creeks, estuaries, marshes, wetlands, inlets, and canals shall first consider vacating the water crossings. For water crossings in all Type F and Type SSBT streams where vacating the water crossing is not feasible or desired by the landowner, permanent channel-spanning structures shall be prioritized before other crossing strategies. This section does not require the landowner to utilize any specific crossing design strategy. (3) Operators shall design and construct permanent water crossings to: (a) Convey, at a minimum, the 100-year peak flow in Type N and D non-fish streams and in Type F and Type SSBT streams. When determining the size of the culvert needed to convey a flow corresponding to the 100-year return interval, operators shall select a size adequate to preclude the ponding of water higher than the top of the culvert. (b) Operators shall design permanent water crossing culverts in Type F and Type SSBT streams using the stream simulation approach. Water crossing design in Type F and Type SSBT streams shall consider and incorporate the stream’s geomorphic processes and anticipated changes over the life of the structure. Operators shall design water crossings in Type F and Type SSBT streams to allow for the movement of water, wood, sediment, and organisms to the maximum extent feasible and minimize obstacles to stream processes. The design of the water crossings in Type F and Type SSBT streams shall avoid fragmentation of aquatic habitats by replicating the natural conditions of the stream being crossed. Where the operator determines it is not possible to achieve stream simulation, operators may propose alternatives if the alternative can accommodate a 100-year peak flow and does not obstruct fish passage. (c) The State Forester may require a larger crossing design if division staff determines, in consultation with department specialists, that the structure size designed to pass the 100-year peak flow is inadequate to: (A) Avoid delivery of sediment to the water being crossed; (B) Avoid stream diversion potential; and (C) Provide opportunity for the passage of expected bed load and associated large woody debris during flood events. (4) Permanent Channel-Spanning Structures. For permanent channel-spanning structures, including long and short-span bridges, and open-bottom culverts, that span the entire bankfull width of the stream, operators shall design and construct the structure to conform with all the following: (a) Permanent channel-spanning structures have at least three feet of clearance between the bottom of the bridge structure and the water surface at the 100-year peak flow, unless engineering justification shows a lower clearance will allow the free passage of anticipated sediment and large wood. (b) Place the bridge structure or stringers in a manner to minimize damage to the stream bed. (c) Tie or firmly anchor one end of each new, or reconstructed, permanent log or wood bridge if any of the bridge structure is within 10 vertical feet of the 100-year flood level. (d) When earthen materials are used for bridge surfacing, install only clean sorted gravel, a geotextile lining or equivalent barrier, and install curbs of sufficient size to a height above the surface material to prevent surface material from falling into the stream bed. (e) Place wood removed from the upstream end of bridges at the downstream end of bridges in such a way as to minimize obstruction of fish passage to the extent practical, while avoiding significant disturbance of sediment in connection with maintenance activities. (f) Abutments, piers, piling, sills, and approach fills shall not constrict the flow so as to cause any appreciable increase (not to exceed 0.2 feet) in backwater elevation (calculated at the 100-year flood level) or channel wide scour and shall be aligned to cause the least effect on the hydraulics of the watercourse. (g) Excavation for and placement of the foundation and superstructure is outside the ordinary high-water line unless the construction site is separated from the stream by an approved dike, cofferdam, or similar structure. (h) Cure wood or other materials treated with preservatives sufficiently to minimize leaching into the water or bed. The use of creosote or pentachlorophenol is not allowed. Cure structures containing concrete sufficiently prior to contact with water to avoid leaching. (i) Design permanent channel-spanning structures in Type F and Type SSBT streams using stream simulation and comply with the following: (A) Channel-spanning structures shall not constrict clearly defined channels; and (B) Channel-spanning structures shall establish a low-flow channel that will allow for fish movement during low-flow periods. (5) Permanent Water Crossing Culverts. For permanent water crossing culverts in all streams, operators shall design and construct culverts to conform with all the following: (a) Design and install culverts so they will not cause scouring of the stream bed and erosion of the banks in the vicinity of the project. (b) Design the culvert to avoid stream diversion potential. (c) The culvert and its associated embankments and fills must have sufficient erosion protection to withstand the 100-year peak flow. Erosion protection may include armored overflows or the use of clean coarse fill material. (d) Place wood removed from the upstream end of culverts at the downstream end of culverts in such a way as to minimize obstruction of aquatic organism passage to the extent practical, while avoiding significant disturbance of sediment in connection with maintenance activities. (e) Limit disturbance of the bed and banks to what is necessary to place the culvert and any required channel modification associated with it. Revegetate, or stabilize with other erosion control techniques, affected bed and bank areas outside the culvert and associated fill with native woody species. Maintain native woody species for one growing season. (f) Do not install permanent water crossing culverts that are less than 18 inches in diameter. (6) Permanent Water Crossing Culverts in Fish Streams. For permanent water crossing culverts in Type F and Type SSBT streams, operators shall conform to (5)(a) through (f) and design and construct culverts using a stream simulation as follows: (a) For no slope culverts and those up to one percent gradient, the minimum culvert diameter or span is at least equivalent to the active channel width. For other culvert installations, the minimum culvert diameter or span is at least 1.2 times the active channel width, plus 2 feet. (b) Alignment and slope. The alignment and slope of the culvert shall mimic the natural flow of the stream when possible. The slope of the reconstructed streambed within the culvert shall approximate the average slope of the adjacent stream from approximately ten channel widths upstream and downstream of the site in which it is being placed, or in a stream reach that represents natural conditions outside the zone of the road crossing influence. (c) Embedment. If a culvert is used, bury the bottom of the culvert into the streambed not less than 30 percent and not more than 50 percent of the culvert height for round culverts and for pipe arch culverts not less than 15 percent and no more than 30 percent For bottomless culverts, design the footings or foundation for the deepest anticipated scour depth. (d) Maximum length. If the design for a new crossing on a new road would require a culvert longer than 150 feet, utilize a channel spanning structure unless the site-specific design constraints preclude the use of a channel spanning structure. (e) Culvert bed materials. Culvert bed materials shall have a similar composition to natural bed materials that form the natural stream channels adjacent to the road crossing in the reference reach. Design the culvert to allow sufficient transported bed material to maintain the integrity of the streambed over time. (A) New water crossings in Type F and SSBT streams shall require manual placement of culvert bed materials during bed construction. (B) Operators may select natural accumulation for reconstruction of water crossings where feasible. Operators that select natural accumulation of culvert bed materials shall document in the written plan the site conditions and design elements that will facilitate natural accumulation in sufficient detail to allow the State Forester to evaluate and comment on the likelihood that the operation will comply with the requirements under (1)(k) and the requirements of (3) and (6) of this rule. (i) The threshold to determine that natural accumulation has occurred shall be when the culvert meets the embedment standard under subsection (6)(c) of this rule. (ii) The operator shall provide the following information in the notification for an extension of a natural accumulation project to the State Forester: (I) An assessment of current culvert bed material accumulation within the culvert; and (II) An assessment of the material available for transport and accumulation within the culvert. (iii) If the culvert does not meet the natural accumulation threshold under (i) after the second winter season following the installation of the crossing and no later than July 1, the operator shall submit a new notification to the State Forester detailing how the operator will mechanically place culvert bed materials in order to achieve (6)(c) before September 30 of the same year. The department shall visually inspect the culvert by December 30 of that year to confirm the crossing meets (6)(c). (f) Water velocity. The maximum velocity in the culvert shall not exceed the maximum velocity in the narrowest channel cross-sections. (7) Fords. For fords, operators shall design and construct those structures to meet all the following criteria: (a) The entry and exit points of a new ford must not be within 100 feet upstream or downstream of another ford within a property ownership. (b) Use fords only during periods of no or low stream flow (whether dry or frozen) to minimize the delivery of sediment to the stream. (c) Install fords only in a dry streambed or when a site is de-watered. The written plan shall describe sediment control and flow routing plans and the project, as implemented, must meet the criteria outlined in the written plan. (d) Approaches to the structure shall not dam the floodplain where substantial overbank flow occurs. (e) The ford shall cross as near to perpendicular to the channel to minimize the disturbance area and reduce post-installation maintenance. (f) The ford shall minimize the acceleration of flow through the ford. (g) For Type F and Type SSBT streams, any ford structure shall: (A) Be no wider than 16 feet; (B) Installed and maintained to ensure scour has not created a barrier to fish passage; and (C) Installed and maintained to ensure free and unimpeded fish passage at all flows when fish are expected to move through the structure. (8) Temporary Water Crossings. For temporary water crossings, operators shall design and construct those structures to conform with the following: (a) Design temporary water crossings in Type N and Type D streams to pass at minimum the flows expected during crossing use with a minimum culvert diameter of 18 inches. (b) Use temporary water crossings in Type F and Type SSBT streams only during the in-water work period defined by the Department of Fish and Wildlife, or when the department in consultation with the Department of Fish and Wildlife and applicant can agree to specific dates of installation and removal, and the extended dates result in equivalent levels of resource protection. (c) Identify temporary water crossings on the forest practices notification and written plan as required in OAR 629-625-0100(2)(d), along with a vacating date. (d) Only use temporary water crossings on Type N and Type D streams: (A) In Western Oregon if installed after June 1 and removed no later than September 30 of the same year; (B) In Eastern Oregon if installed after July 1 and removed no later than October 15 of the same year; or (C) When the department and applicant agree to specific dates of installation and removal, and the extended dates result in equivalent levels of resource protection. The department may consult with Department of Fish and Wildlife before extending the dates. (e) Install temporary water crossings in the dry streambed or in isolation from stream flow by the installation of a bypass flume or culvert, or by pumping the stream flow around the work area. The State Forester may grant an exception to the operator if siltation or turbidity is reduced by placing the culvert in the flowing stream as an alternative to dewatering . (f) Limit the bypass reach to the minimum distance necessary to complete the project. (g) Vacate temporary water crossings to the specifications outlined in OAR 629-625-0650. (h) The State Forester may waive removal of the water crossing if the operator secures an amended written plan, and the structure and its approaches meet the requirements of a permanent water crossing structure as outlined in Sections (4) to (7) of this rule. (i) Limit the disturbance of the bed and banks to that which is necessary to place the temporary water crossing and any required channel modification associated with it. (9) Other Design Strategies. The operator shall submit their design strategies to the State Forester for approval: (a) Submit any alternative water crossing strategy that does not conform with sections (4) to (8) of this rule to the State Forester as a plan for alternative practice. The State Forester may approve the plan for alternate practice in consultation with Department of Fish and Wildlife. (b) The State Forester may consider other designs if they can meet or exceed the standards in sections (4) to (8) of this rule. (10) Construction of Water Crossings. In the construction of water crossings, operators shall do the following: (a) Comply with all relevant forest road construction and maintenance rules in the construction or reconstruction of all water crossings. Nothing in this section affects existing requirements of Department of Fish and Wildlife. (b) Runoff, Erosion and Sediment. Operators shall control runoff, erosion, and sediment through the following actions: (A) Include a site-specific erosion and sediment control plan as part of a written plan prior to beginning work. This plan must include, but is not limited to: (i) A site plan with a description of the methods of erosion or sediment control; (ii) Methods for confining, removing, and disposing of excess construction materials; and (iii) Measures to disconnect road surface and ditch water from all typed waters and lakes, bays, ponds, impounding reservoirs, springs, rivers, streams, creeks, estuaries, marshes, wetlands, inlets, and canals. (B) Treat areas of bare soil that could deliver sediment to all typed waters and lakes, bays, ponds, impounding reservoirs, springs, rivers, streams, creeks, estuaries, marshes, wetlands, inlets, and canals. Treatments must include, but are not limited to: (i) Prior to project construction, establish effective drainage; before September 30 in Western Oregon and October 15 in Eastern Oregon. Effective drainage may be established at other times when the department and applicant can agree to specific dates of installation and removal, and the extended dates result in equivalent levels of resource protection; (ii) Before the start of the rainy season and no later than September 30 in Western Oregon and October 15 in Eastern Oregon , mulch or seed areas of bare soil, or any combination thereof to reduce surface erosion; and (iii) Upon completion of construction, apply native seed, invasive species-free mulch, or any combination thereof to sites with the potential for sediment delivery to all typed waters and lakes, bays, ponds, impounding reservoirs, springs, rivers, streams, creeks, estuaries, marshes, wetlands, inlets, and canals. Operators must apply invasive species-free mulch to stay in place. (c) Pollution Control. To control pollution, operators shall do the following: (A) The operator shall maintain a spill prevention and response plan on site during construction. (B) The operator shall not allow uncured concrete or concrete by-products to enter waters of the state during construction. The operator shall seal all forms for concrete to prevent uncured concrete from entering waters of the state. (C) The operator shall take measures to ensure that all materials and equipment used for construction, monitoring, and fish salvage are free of aquatic invasive species. (D) The operator shall not use wood treated with creosote or pentachlorophenol for parts of the structure in or over the active channel, including pilings, beams, structural supports, and decking. (E) The operator shall not allow chemicals or any other toxic or harmful materials to enter into waters of the state. (d) In-Water Work, Worksite Isolation, and Dewatering. To address in-water work, worksite isolation and dewatering needs of water crossing projects, operators shall do the following: (A) Develop an in-water work plan for water crossings in all typed waters and lakes, bays, ponds, impounding reservoirs, springs, rivers, streams, creeks, estuaries, marshes, wetlands, inlets, and canals in their written plan. The plan may include, but is not limited to, fish salvage, worksite isolation, and dewatering. The written plan shall address in detail all in-channel construction activities and how the activities will adhere to all relevant forest practice rules forest road requirements. For all streams, the written plan shall describe: (i) Activities during the in-water work period defined by the Department of Fish and Wildlife; or (ii) Activities outside the in-water work period when the department, in consultation with Department of Fish and Wildlife, and applicant can agree to specific dates of installation and removal, and the extended dates result in equivalent levels of resource protection. (B) Construct water crossings in compliance with Department of Fish and Wildlife fish passage and in-water work period requirements. (C) For all water crossings in Type F and Type SSBT streams, operators shall do the following: (i) Worksite isolation: (I) Operators must isolate any work area within the width of the bankfull channel from water in the active channel at times when fish are reasonably certain to be present in a Type F or Type SSBT stream. (II) When constructing water crossings in Type F and Type SSBT streams with any stream bypass, operators shall have an exclusion and recovery plan to ensure safe capture and relocation of fish trapped in the work zone when stream flow has been diverted. (III) Prior to construction site dewatering, operators shall capture and relocate fish to avoid direct mortality to the maximum extent practicable. (IV) Operators shall salvage fish to the maximum extent practicable at any in - water construction site where dewatering and resulting isolation of fish may occur. (V) Operators shall remove all isolation features after construction is complete and submit a written salvage report to the department. (ii) Dewatering: (I) Operators shall not dewater areas known to be occupied by lamprey, unless the operator submits a lamprey salvage plan to the State Forester in consultation with the Department of Fish and Wildlife. (II) Operators shall conduct dewatering of the isolated area in a manner that prevents sediment-laden water from reentering the stream. (III) Operators shall limit dewatering to the shortest linear extent of the stream as practicable. (IV) Operators shall conduct dewatering over a sufficient period to allow species to naturally migrate out of the work area. (11) Monitoring. Landowners shall develop and implement a monitoring program for periodic inspections of all Type F and Type SSBT stream crossings that includes: (a) Visual inspection to confirm that the crossing is functional; and (b) Monitoring occurs at least once every 5 years.