Fig. 79: Erosion and Accretion near Godavari river

Use of Geospatial Technologies

The present study uses robust Aerial photo and high-resolution satellite imagery for mapping shoreline positions. High-end LiDAR technology integrated with GNSS/IMU system has been used to acquire the aerial photographs. NCSCM used 9 cm GSD aerial photographs for the year 2011-2012 prepared by Survey of India as the base data to geo-reference all the other high resolution satellite images.

Key Outputs

y Flood lines were mapped and plotted on 0.5 m Digital Elevation model (DEM) based on a 100-year return period interval. y Historical shoreline trends from 1975 to 2011 were extrapolated to predict future shoreline positions for the next 100 years y A composite hazard line was prepared by superimposing flood lines and erosion lines to demarcate the maximum flood line on the Digital Elevation Model (DEM). y A national database indicating coastal erosion/accretion map based on linear regression rate was

Fig. 79: Erosion and Accretion near Godavari river

y prepared on 1:10,000 scale. y The predicted shoreline (after 100 years: 2110) drawn on high resolution satellite imagery/ ortho-photos was prepared on 1:10,000 scale