2012 Annual Report
1a.Objectives (from AD-416):
To demonstrate state of the art of sediment budgeting and reservoir sediment surveying techniques to Jomo Kenyatta University of Agriculture and Technology in Kenya for water supply planning and cost-effective allocation of best management practices within the Ruiru Reservoir watershed.
1b.Approach (from AD-416):
The Ruiru Reservoir watershed, located in Nairobi, Kenya, will be evaluated using standard rapid geomorphic assessment techniques to determine probable sources of sediment. A vibracoring system, boat, and outboard motor and gas tank will be purchased by Jomo Kenyatta University of Agriculture and Technology (JKUAT) from Specialty Devices, Inc. and transported to Kenya, while the multifrequency acoustic profiling system (APS) will be rented by USDA ARS from Specialty Devices, Inc. (Wylie, TX) and shipped to Kenya. Reservoir water storage capacity and long-term average annual sedimentation rates will be quantified using the bathymetric survey using the APS. Sediment cores will be taken from the reservoir during the wet season using the vibracore and analyzed to determine the sediment texture and bulk density. In addition, since the Ruiru reservoir was impounded prior to 1963, 137Cs analysis will be done to give early and late sedimentation rates. The sediment budget/sources information and reservoir sedimentation rates will be used to calibrate and validate the Soil and Water Assessment Tool model project for the Ruiru Reservoir. Kenyan personnel will be trained in using the APS, vibracore, and rapid evaluation of sediment budget methods.
We are in the process of gathering the equipment; bathymetric survey will be carried out in December 2012.