Sedimentation Analysis of Dam Using GIS Techniques
The vital source of water supply are reservoirs which also provide hydroelectric power, sustain diverse aquatic habitat & provide protection from flood. Sedimentation in reservoirs is major issue as they bear a huge loss in their storage capacity potential because of silt deposition, for long or short duration of time which gradually reduced the effectiveness of dam operations over the years. This research paper presents Geographical Information Systems (GIS) based application for analyzing sediment deposits of Khadakwasla Dam located on the Mutha river in Pune, Maharashtra. The purpose of the present study is to assess the quantity of suspended sediments in the dam basin using the GIS, remote sensing facilities & satellite imageries of powerful sensors in the field of water studies and then comparing the results with sediment data. Some conventional methods such as hydrographic survey, bathymetric survey etc. are used for evaluation of sediment deposition which are cumbersome and time consuming, requires skilled persons, inconvenient, expensive, etc. Therefore, GIS & Remote Sensing approach, which provide high resolution synoptic and repetitive data information with short time intervals on a large scale, requires less time, with greater accuracy & precision has been attempted in this study for sedimentation analysis. Spatial data were collected from aerial photographs, bathymetric survey data & satellite images corresponding to the study area. Multiple date remote sensing data i.e., Landsat-7 data for the water year 2018-19 is acquired in this study. For increase in accuracy, NDWI approach using GIS has been applied for identification of water pixels and water spread area of the reservoir, which is utilized for determination of sedimentation rate.
Keywords - Geographical Information System (GIS), Remote Sensing, Sediment Deposition in dam