From the eastern part of the Kiwalik River basin, the streams emanating from the east are the Quartz and Hunter creeks. Quartz Creek, with a larger catchment (rugged and hilly on the eastern and southern borders of the basin) joins the Kiwalik River, about above the mouth of Glacier Creek. A thin layer of moss covers the floor of the basin. The hill slopes are steep and precipitation drains out fast over the river bed which consists of loose gravel. Other streams that flow through the basin and which join the Quartz Creek are the Hunter Creek and Bear Creek; the former creek has lesser flows compared to Quartz Creek. Lava Creek, another small tributary from the east that drains a flat lava area in the north of Hunter Creek, has high runoff during the rainy months. The banks of the river and the creeks are lined with spruce and also willow vegetation, in specific stretches.