WATER RESOURCES RESEARCH GRANT PROPOSAL
WATER RESOURCES RESEARCH GRANT PROPOSAL
Project ID: 2002OR2B
Title: Temperature Effects of Streambed Heating
Project Type: Research
Focus Categories: Water Supply, Models, Sediments
Keywords: Sediment heating, Streambed heating, water quality modeling, water temperature
Start Date: 02/15/2002
End Date: 02/14/2003
Federal Funds: $14,998
Non-Federal Matching Funds: $30,618
Congressional District: Oregon 1st
Principal Investigators:
Scott A. Wells
Portland State University
Robert L. Annear
Portland State University
Abstract
Stream temperatures are a major issue in Oregon both for salmonid habitat requirement and for meeting state water quality requirements. Much research has been done in characterizing the forcing functions influencing stream temperature. Recent work by the State of Oregon has enhanced temperature modeling in streams by accounting for shading effects of short wave solar radiation. An important part of the heat balance though for shallow streams exposed to short wave solar radiation is the impact of streambed heating. In shallow clear streams, the penetrating short-wave solar radiation that reaches the channel bottom can be absorbed by the channel substrate during the day and this energy later released at night based on the temperature differential between the substrate and the channel bed. We propose to develop a streambed-heating algorithm for use in stream temperature models. This algorithm will be initially incorporated into the 2-D hydrodynamic and water quality river-basin model called CE-QUAL-W2 and used in the Willamette River Basin TMDL for temperature. The algorithm though will be generally available for use in other stream temperature prediction models, such as the DEQ Heat Source model. CE-QUAL-W2 already accounts for all terms of the surface heat balance equation, including dynamic vegetative and topographic shading. This algorithm will be compared to field data collected from two stream systems: one in the Bull Run River (below the City of Portland Bull Run Reservoir 1) and the other in the upper Clackamas River basin at Eagle Creek. The purpose of this refinement is to improve the ability to predict the impacts of management changes on stream temperatures.