Technical Bulletin No. 0828: The Effects of an Unbleached Kraft Mill Effluent on Periphyton and Macroinvertebrates in Streamside Mesocosm Studies

On-site experimental streams were constructed at an unbleached kraft mill on the McKenzie River in order to interface dose-response studies with ongoing in-stream monitoring activities. Algal colonization was monitored in flow-through troughs with 0, 1, and 5% v/v effluent in April, 1999. A combination of factors, including unusually low river water levels, pump selection, and pump placement, resulted in transport of excess fine sediments into the experimental troughs such that periphyton colonization was inhibited.