OAR 635-400-0010

As used in these rules:


“Application” means an official instream water right application developed by the Water Resources Department.


“Commission” means the Fish and Wildlife Commission.


“Department” means the Department of Fish and Wildlife.


“Deputy Director” means the deputy director of the Department.


“DEQ” means the Department of Environmental Quality.


“Director” means the director of the Department of Fish and Wildlife.


“Environmental Basin Investigation Reports” means reports on instream flow studies conducted by the OSGC between the mid-1960s and the mid-1970s.


“Forest Service Method” means a methodology developed by the Pacific Northwest Region, USDA Forest Service, to determine instream flow requirements of salmonids (Swank, G. W. and Phillips, R.W. 1976. Instream flow methodology for the Forest Service in the Pacific Northwest Region, pp 334–343. In Proceedings of Symposium and Special Conference on Instream Flow Needs, Orsborn, J.F. and O.H. Allman, eds. Vol. II, American Fisheries Society, Bethesda, Maryland).


“Held in Trust by the Water Resources Department,” as defined in OAR 690-077-0010 (Definitions)(8), means that the water right must be enforced and protected for the public uses listed in the water right. Actions by the Water Resources Department affecting instream water rights are limited by public trust obligations.


“IFIM” means Instream Flow Incremental Methodology, a methodology to determine instream flows for fish and other aquatic life, developed by the U.S. Fish and Wildlife Service (Bovee, K.D. 1982. A guide to stream habitat analysis using the instream flow incremental methodology. Information Paper No. 12, U.S. Fish and Wildlife Service, FWS/OBS-82-26, Fort Collins, CO).


“Instream Flow Requirement” means the amount of water required for aquatic and fish life, wildlife or fish and wildlife habitat. This requirement may be quantified as an amount of flow, such as in a stream or river, or a water surface elevation in a standing waterway.


“Instream Water Right,” as defined in ORS 537.332 (Definitions for ORS 537.332 to 537.360)(2), means a water right held in trust by the Water Resources Department for the benefit of the people of the State of Oregon to maintain water in stream for public use. An instream water right does not require a diversion or any other means of physical control over the water.


“Oneflow Method” means a methodology to determine instream flow requirements for salmonid spawning areas based on the mean width, depth and velocity of water in a stream channel at one measure flow (Sams, R.E. and L.S. Pearson, 1963. A study to develop methods for determining spawning flows for anadromous salmonids. Unpublished report, Oregon Fish Commission, Portland, Oregon. 56 pp.).


“Oregon Method” means a methodology to determine instream flow requirements for fish, developed by the OSGC (Thompson, K.E. 1972). Determining streamflows for fish life. pp. 31–50. In Proceedings of the Instream Flow Requirement Workshop, Pacific N.W. River Basins Commission, Portland, Ore.


“OSGC” means Oregon State Game Commission (a predecessor to the Department).


“Parks” means the Parks and Recreation Division of the Department of Transportation.


“Public Use” as defined in ORS 537.332 (Definitions for ORS 537.332 to 537.360)(4), includes but is not limited to:




Conservation, maintenance and enhance-ment of aquatic and fish life, wildlife, fish and wildlife habitat and any other ecological values;


Pollution abatement; or




“State Sensitive and State or Federally Listed Threatened or Endangered Species” means those species defined in ORS 496.004 (Definitions) and OAR 635-100-0001 (Wildlife Diversity Plan Definition of Terms) and determined through ORS 496.172 (Commission management authority for threatened or endangered species) through 496.176 (Listing species) or through the federal process.


“Stream order” means a widely accepted system of classifying streams. First order streams have no tributaries and are often called headwater streams. When two first order streams meet they form a second order stream. the joining of two second order streams form a third order stream and so on. When two streams of the same order meet the next higher order is formed.


“Waterway” means a stream, lake or place where water naturally occurs.


“WRD” means the Water Resources Department.
[Publications: Publications referenced are available from the agency.]
Last Updated

Jun. 8, 2021

Rule 635-400-0010’s source at or​.us