MTech.

The knowledge of temporal distribution of sediment yield is required in
the design and operation of soil and water conservation programmes on
watershed basis. For the project planning purposes, the estimates made are
mostly based on experience. Such estimates are very approximate and grossly
inadequate for engineering analysis. Therefore there is an urgent need for
,
rational analysis of erosion data from catchments, inorder to obtain relationship
for erosion rate. Therefore a mathematical daily sediment yield model is
developed for Thuthapuzha drainage basin (940 km2 ) of Bharathapuzha basin,
corresponding to Muskingum routing equation. The model is based on
combined approach of translation and routing for simulating sediment graphs.
Thirty seven selected storm events of the drainage basin observed during 1986-
92 are used for estimation of model parameters by Lagrange multipliers method
and three storm events of 1993 are used for verification of the model.
The model is used to compute temporal distribution of suspended
sediment yield on storm basis and their performance is evaluated both
qualitatively and quantitatively. Mathematical relationships of mobilized
~
sediment with effective rainfall; computed sediment flow rates with observed
sediment flow rates and observed and computed sediment flow with effective
rainfall and mobilized sediment were also established. The Correlation
Coefficient of all those equations are found to be close to one. The statistical
measures of Percentage Absolute Error in peak sediment flow rates, Absolute
Prediction Error, Integral Square Error, Correlation Coefficient and Coefficient
of Efficiency of the model are obtained as 3.9934, 9.0007, 5.3286, 0.9951 and
0.9659 respectively. The study reveals that the developed model is a very
effective tool in the real time forecasting of sediment yield in Thuthapuzha
drainage basin.