OAR 635-430-0340: Factors for Determining Width of Riparian Lands

The Department may designate qualifying perennial and intermittent streams and associated riparian lands up to 100 feet landward (horizontal measurement) from the line of non-aquatic vegetation adjacent to the stream, or an area not exceeding 25 acres of riparian lands per mile of stream, as riparian lands. To determine the width of the land actually designated as riparian land, the Department will consider the following factors necessary to promote erosion control, long-term stream bank stability, water quality, fish and wildlife habitat protection, conservation or restoration, large wood recruitment and other functions deemed important to healthy aquatic habitat: (1) Stream size at various flows; (2) Existing riparian vegetation and vegetation restoration potential; (3) Stream bank slope; (4) Adjacent land uses; (5) Stream channel orientation; (6) Space necessary to establish and protect riparian fences or other structures needed to implement measures specified in an approved riparian management plan and agreement; (7) Potential for lateral channel migration or new channel formation and any constraints on such migration or formation; and (8) Location of stream-associated wetlands or off-channel features such as alcoves, oxbows, side channels or other areas important to fish and wildlife habitat.