Measuring Seepage through Salmon Spawning Gravel

Abstract

The rate of oxygen supply to salmon eggs incubating in a stream bed depends on the oxygen concentration in the groundwater and the rate of seepage through the redd. Wickett (1954) devised a simple field method of both sampling the groundwater for the determination of its dissolved oxygen content and measuring the seepage rate, using one tool, a standpipe. The theory of seepage is outlined to show the factors governing the velocity of flow through a redd. Alternative ways of measuring this velocity were examined; the best one is a modification of Wickett's procedure using a similar standpipe. A new field procedure for measuring the oxygen concentration and groundwater seepage rate in a stream bed is recommended.