The following characteristics were studied in a small salmon stream in Southeastern Alaska from 1956 through 1959: 1) dissolved oxygen content of ground water, 2) variation of dissolved oxygen with depth in streambed, 3) temperature of ground water, 4) extent of ground-water seepage, 5) interchange of flowing stream water and water of streambed gravels, and 6) flow of water in the gravel of streambank and gravel bar. Ground water was generally low in dissolved oxygen content, and dissolved oxygen levels decreased with depth in streambed. Because of these and other points discussed in this paper, the main source of intragravel water of high oxygen content is the flowing stream.