January 1998

Volume 51: 88-90

Technical Note:

Stream temperatures as related to subsurface waterflows originating from irrigation

Tamzen K. Stringham, John C. Buckhouse, and William C. Krueger
Authors are graduate research assistant, professor and department head, Department of Rangeland Resources, Oregon State University, Corvallis, Ore. 97331

Abstract

Continuous stream temperature data were collected from adjacent reaches of a third-order stream in eastern Oregon. The upstream reach was located within a non-irrigated meadow and the downstream reach was located within an irrigated meadow. Sensors were placed in the stream above a head-ditch irrigation diversion, in the irrigation ditch, in the subsurface (interflow) groundwater, and in the stream reach within the irrigated meadow. Daily maximum stream temperature in the reach located within the irrigated meadow was found to be 1 to 3oC cooler than the non-irrigated reach. Daily minimum stream temperatures exhibited the opposite relationship with the reach within the irrigated meadow ranging from 0.5 to 1.7oC warmer than the non-irrigated meadow reach.

Key Words: stream temperature, groundwater, subterranean return flow