Sample collection for M/s NHPC sponsored project. M/s NHPC Ltd has awarded a project to NCB for site inspection of the silt and water quality of River Dibang at lower Dibang valley for the proposed dam construction. The project work envisages petrogarphic analysis of silt, langelier�s saturation indices, physical and chemical properties of the river samples of Dibang river during the monsoon and non � monsoon period. The petrographic analysis of the silt from the river dibang will help in designing of the dam turbines and also estimate the tendency of silt particles to settle in the water reservoirs.