High-Resolution Hydrological Mapping and Watershed Analysis of Sitamarhi District using Photogrammetry and Satellite Imagery

This project, executed by SATPALDA Geospatial Services, aimed to conduct detailed hydrological studies across the Sitamarhi district of Bihar, India. Situated near the Nepal border and rich in cultural heritage, Sitamarhi is characterized by fertile plains and crisscrossing river networks such as Baghmati, Aghwara, Lakhandei, and Manusmara. The project sought to map these water bodies, including streams, ponds, and canals, to support watershed sustainability and environmental resource planning. A 50cm stereo imagery from the WorldView-2 satellite was acquired to provide high-resolution inputs. 

DGPS surveys with precision GCPs enhanced the geospatial accuracy. Aerial Triangulation helped align images to ground coordinates, leading to the generation of a 1-meter resolution Digital Terrain Model (DTM) and corresponding 1-meter interval contour maps. Critical hydrological and terrain features were extracted in 3D to offer insights into elevation and drainage patterns. Rigorous multi-level QC protocols ensured data reliability. The final deliverables included orthoready satellite images, DGPS survey reports, DTM (TIFF), and contour maps (DWG).