Extensive high-quality hydrologic and sediment yield data would greatly aid planning for the use of water resources of the Sutlej River system. The total catchment within the mountains is 47,480 km247,480 km2, with the Spiti and Kinnaur tributaries accounting for 5,875 and 5,157 km25,157 km2, respectively, in India. By far the largest part lies in Tibet. This paper attempts to utilize the available data to provide a first estimate of the magnitude of the problem facing development engineers. It is concluded that extensive sediment control treatment will be necessary to improve the safety and efficiency of the many hydroelectric projects that are being planned for the Sutlej and its tributaries which drain from the Himalaya. Nine years of discharge and sediment yield data collected daily from calibrated sections of the rivers form the basis for this study. While the monthly and annual runoff data show little variation throughout the period, sediment yield was extremely variable. About 80 percent of the annual flow occurs between May and September, mainly from snowmelt. Sediment yield increased exponentially with increased discharge, with especially high concentrations from June through August. The main sediment sources are gully erosion, stream-bank erosion, landslides, road construction, and glacier erosion. The sediment from this region accounts for half the annual accumulation in the Bhakra reservoir farther downstream.