Estimation of runoff volumes and peak rates from rural catchments in Kenya
Abstract
The estimation of runoff volumes and peak rates of runoff
was carried out in two rural catchments in Kenya. The
catchments viz., Sambret (7.02 km2) and Lagan (5.44 km2) lie
in the headwaters of the lake victoria drainage basin. Both
were selected on the basis of availability of
hydrometeorological data required for calibration and
testing of the models. In Sambret catchment, out of the 41
rainfall-runoff events, 25 were used for model calibration
while 16 events were used for testing. The calibrated and
verified models were further tested in the neighbouring
Lagan catchment using 18 events.
Results from the runoff volume models showed that the USSCS
(United states Soil Conservation Service) curve number
and the API (Antecedent precipitation Index) models gave
satisfactory results in both Sambret and Lagan catchments.
However, SCS curve number performed better than API model.
Nash model predicted the peak runoff rates better than
kinematic'wave and SCS triangular hydrograph models in both
Sambret and Lagan. Kinematic wave gave acceptable results
in Sambret while in Lagan it under predicted the peak
runoff rates. The SCS triangular hydrograph over predicted
the peak discharges in both catchments indicating that it
has limited applicability in the headwaters of lake
victoria drainage basin in Kenya.
Citation
Onyando, J.O(1994). Estimation of runoff volumes and peak rates from rural catchments in KenyaSponsorhip
University of NairobiPublisher
Department of Agricultural Engineering, University of Nairobi
Description
Msc Thesis