Channel morphology and prediction of mid-line channel migration in the reach of Ganga River using GIS and ARIMA modeling during 1975–2020

Abstract

The dynamic nature of meandering poses several challenges in a river. The river Ganga shows severe bank erosion in many of its stretches which creates insecurity to the habitats. In the present study, channel morphology and lateral mid-line migration for 1975 to 2020 in 5 years intervals have been studied. The prediction of lateral mid-line migration from 2020 to 2050 by using multi-temporal Landsat satellite images was made by using the ARIMA model. The river reach was divided into 8 bends and 48 cross-sections were identified. The channel length was observed as 224.35 km in 1975 which reduces to 199.96 km in 2020. A decreasing trend was observed for the mean of channel length and meander ratio, and an increasing trend was noted in the mean of sinuosity ratio and tortuosity ratio. A total of 11 cross-sections showed the rightward shifting and 36 cross-sections showed the leftward shifting. Observed and predicted values showed a good R2 value of 0.90 and 0.89 at CS-24 and CS-25, respectively. The results may be used for planning and management of various river training work and understanding the river system dynamics. HIGHLIGHTS To investigate the variations in river morphometric parameters of the river Ganga.; Prediction of centerline channel shifting in the middle part of river Ganga from 1975 to 2050.; Outcome of the proposed research will definitely help the government in decision making, management and implementation of future projects.;

Keywords

• arima model
• channel morphology
• ganga river
• gis and remote sensing
• lateral mid-line channel shifting