Abstract Fourteen-month velocity records from five moorings along Long. 175°W, in combination with CTD and nutrient data, distinguish two pronounced, quite steady, deep zonal currents near the northern margin of the North Pacific. One flows westward at speeds of 1–3 cm s −1 along the slope of the Aleutian Island Arc, and appears to be the northern-boundary current required by deep circulation theory. The other flows eastward at about 1–2 cm s −1 just to the south above the Aleutian Trench and upper Aleutian Rise, and carries water that is slightly lower in temperature and dissolved silica, and slightly higher in salinity and dissolved oxygen, than that to the north or south. We believe that this eastward jet represents an extreme distortion of a level-bottom, interior flow pattern, as forced by the meridional variation in bottom slope on the southern flank of the Aleutian Rise, which imposes a varying effective “beta” on the system. A simple model of this effect is discussed.