603-095-3740 Required Prevention and Control Measures (1) All landowners or operators conducting activities on agricultural and rural lands are provided the following exemptions from the requirements of OAR 603-095-3740 (Prevention and Control Measures). (a) A landowner or operator shall be responsible for only those conditions caused by activities conducted on land managed by the landowner or operator. (b) Rules do not apply to conditions resulting from unusual weather events or other circumstances not within the reasonable control of the landowner or operator. Within the reasonable control of the landowner means that technically sound and economically feasible measures must be available to address conditions described in Prevention and Control Measures. (c) The Department may allow temporary exceptions when a specific integrated pest management plan is in place to deal with certain weed or pest problems. (2) Waste Management: Effective upon rule adoption, no person subject to these rules shall violate any provision of ORS 468B.025 or ORS468B.050. (3) Nutrient Management: Effective upon adoption. (a) Landowners and operators shall prevent the runoff or leaching of contaminated water from feed and manure storage piles into waters of the state, including but not limited to groundwater. (b) Landowners or operators shall store, use, and apply crop nutrients in a manner that prevents transport into the waters of the state. (4) Erosion Management: Effective upon rule adoption, there shall be no visible evidence of erosion resulting from agricultural activities in a location where erosion contributes, or may contribute, sediment to waters of the state. (a) Visible evidence of erosion consists of one or more of the following features: (A) Sheet wash, noted by visible pedestalling, surface undulations, and/or flute marks on bare or sparsely vegetated ground; or (B) Visibly active gullies, as defined by OAR 603-095-0010 (1); or (C) Multiple rills, which have the form of gullies, but are smaller in cross sectional area than one square foot; or (D) Visible soil deposition that could enter natural stream areas; or (E) Streambanks breaking down, eroding, tension-cracking, shearing or slumping beyond the level that would be anticipated from natural disturbances given natural hydrologic characteristics; or (F) Underground drainage tile outlets either improperly installed or maintained allowing soil or bank erosion to actively occur. (b) Private roads used for agricultural activities shall be constructed and maintained such that road surfaces, fill, ditch lines, and associated structures are designed and maintained to prevent and control contributing sediment to waters of the state. All private roads not subject to the Oregon Forest Practices Act are subject to this regulation. (c) Drainage and irrigation ditch construction and maintenance must be done such that: (A) Ditch slope and ditch cross section are designed for the local soils and minimize erosion; (B) Placement of disposed soils is done in a manner that prevents reintroduction to waters of the state; and (C) Other appropriate best management practices are employed when necessary, so that sediment delivery is consistent with water quality standards. (5) Riparian Management: Effective upon rule adoption. (a) Agricultural activities will allow for the development of riparian vegetation along all streams, consistent with site capability, to provide: (A)Shade for minimizing solar heating of the stream; (B)Streambank stability from flows at or below those expected to occur during or following a 25-year, 24-hour storm event; (C) Filtration, settlement, and biological uptake of sediment, organic material, nutrients, and pesticides in surface runoff by intercepting or slowing overland flow; (b) If any agricultural activity disturbs enough streamside vegetation to impair the conditions and functions described in 603-095-3740(5)(a), the landowner or operator must replant or restore the disturbed area with vegetation that will provide the functions required in 603-095-3740(5)(a)(A)(B)(C). (A) Management activities within the riparian vegetation area are allowed provided they do not compromise achieving the conditions described in 603-095-3740(4) and 603-095-3740(5)(a). (B) Drainage and irrigation ditches are not subject to the riparian management provisions cited above but are subject to OAR 603-095-3740(4). Statutory/Other Authority: ORS 561.190 - 561.191 & 568.912 Statutes/Other Implemented: ORS 568.900 - 568.933 History: DOA 86-2026, minor correction filed 02/26/2026, effective 02/26/2026 DOA 19-2025, amend filed 09/23/2025, effective 09/23/2025 DOA 4-2004, f. & cert. ef. 1-23-04