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The dynamic relationship between ground water and the Columbia River: Using deuterium and oxygen-18 as tracers

K. A. McCarthy·W. D. McFarland·J.M. Wilkinson·L. D. White
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Abstract

Deuterium and oxygen-18 were used as natural tracers to investigate the hydraulic relationship between the Columbia River and the Blue Lake gravel aquifer near Portland, Oregon. A time series of stable-isotope data collected from surface and ground waters during a March 1990 aquifer test confirms that the river and aquifer are hydraulically connected. Calculations based on simple mixing show that the river contributed 40–50% of the yield of three wells after 5–6 days of pumping. Data collected during August 1990, show that the river contributed 65–80% of the yield of one well after 22 days of pumping and indicate that the contribution of the river was still increasing.

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K. A. McCarthy, W. D. McFarland, J.M. Wilkinson, L. D. White. 1992. The dynamic relationship between ground water and the Columbia River: Using deuterium and oxygen-18 as tracers. https://doi.org/10.1016/0022-1694(92)90078-a

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