 Based on per capita income, one of the more reliable measures of affluence, Walnut Grove ranks 78th of 522 areas in the state of Washington to be ranked.Walnut Grove is located in southern Clark County at (45.674272, -122.601267).It is bordered by the city of Vancouver to the southeast and west, and by the suburbs of Minnehaha to the south, Hazel Dell to the west, Salmon Creek to the northwest, Barberton to the north, and Five Corners to the east.