Analysis of Variation of Flow and Sediment Discharge in Narmada River

The present paper discusses the changes in the trend of the suspended sediment load transport in Narmada River. Large variation in sediment load is observed from year to year. No sediment load is observed during non-monsoon period while high sediment concentration and flow occurs in the monsoon period for the year 1987 to 2005 accounting for the total load transported during these years. Monthly, seasonal and annual trends of suspended sediment load and flow have been studied for eight years, from 2005 to 2013. The correlation between sediment concentration and river discharge for the year 2005, 2012 and 2013 was found to be very good with a R² value of 0.8, 0.82 and 0.88 respectively. It can be concluded that river discharge is one of the dominant and reliable variable to predict the sediment concentration. For some observations, the change in the flow rate and suspended load (SL) concentration is very rapid and random and thus unpredictable. Applicability of the SL equations is also checked by comparing the estimated load and observed SL measured at Manot gauging station. Statistical analysis revealed that SL equation of Celik and Rodi (1991) and Wiuff (1985) under-predict while Bagnold (1966) and Habibi and Sivakumar (1992) over-predict for Narmada River at selected gauging station. The findings and suitability of the USP based sediment transport formula in predicting total sediment transport rate is also discussed in the context of present analysis.

Keywords: Suspended sediment trend, river discharge, Total sediment load, Narmada River