Seasonal variation in water quality was compared for the Western Fish Toxicology Station (WFTS), Corvallis, OR, the adjacent Willamette River and approximately 40 major western Oregon rivers from 1972 through 1974. Water temperature patterns of the Willamette River and the WFTS well were similar (range, 4.6-20.OC). While both displayed seasonal trends, well water lagged 7-10 days behind the river in both temperature increases and decreases. Dissolved oxygen values in both the river and well water were inversely related to temperature. Average dissolved oxygen concentrations were higher in the river (10.4 mg/l) than in the well water (4.1 mg/l). Hydrogen ion concentration (pH) was low in the well water (range, 6.6-7.0), compared to the river (range, 7.0-7.8). River water had a mean hardness and alkalinity of 22 mg/l and 23 mg/l respectively, while well water ranged between 'soft to moderately hard' (mean hardness, 34 mg/l; mean alkalinity, 31 mg/l). River iron and manganese concentrations were approximately 10 times greater than those found in the well. River zinc had a mean of 9.4 ug/l, while the well water mean concentration was 5.1 ug/l.

Includes appendices. Includes bibliographical references (pages 38-39).