Jordan and Fanjoy, page 1 Sediment yields and sediment budgets of community water supply watersheds in southeastern British Columbia.

Abstract: Over the past 10 years, the B.C. Forest Service has measured sediment concentration and turbidity on a number of creeks in the Kootenay region of British Columbia, which are used for community or domestic water supply. This paper summarizes the results of measurements on 11 forested watersheds. Some of them have streamflow stations, so that suspended sediment data collected for water quality purposes can be converted to sediment yield. Reasonable estimates of discharge and yield can be made for the remaining creeks. Both undeveloped and developed watersheds are included. For most watersheds, annual background suspended sediment yields are comparable to or slightly higher than the range of published Water Survey of Canada results for small forested watersheds (about 3 to 10 t/km2/y). These yields are lower than for most watersheds in British Columbia. Streams with low sediment yield have been chosen by communities as water sources because they provide good quality water. In some watersheds with forestry development, sediment yield is significantly greater than background levels, due mainly to erosion from logging roads. However, in most cases, the amount of sediment is still within generally accepted water quality guidelines. In rare cases, landslides caused by forest roads have resulted in very large increases in sediment yield