Application of GIS to Determine Storage Volume and Surface Area of Reservoirs: The Case Study of Buyuk Karacay Dam

Abstract

Geographic Information Systems (GIS) are widely used in hydrological studies. Digital Elevation Model (DEM) was generated by using
topographic map of Buyuk Karacay basin. This map can be used to determine basin characteristics, stream network, storage volume of reservoirs
and surface area of the storage volume. In this study, Buyuk Karacay Dam which is still under construction in Hatay province of Turkey was chosen
for the case study. Reservoir storage volume for the dam was estimated using the Ripple method. Procedures to determine storage volume according
to the crest elevation are described. The maps of flow accumulation, flow direction, drainage network and surface area of storage volume maps were
generated from DEM using Ilwis 3.6 GIS software and elevation-volume and elevation-area graphics were presented. According to Ripple method,
dam reservoir storage capacity was found as 84 hm3, in this capacity, estimated crest elevation was 360 meters from elevation-volume graphic and
water surface area at the same storage capacity estimated to be 2.64 km2 using elevation-area graphic. GIS application provides useful information
for water manager and planners. Water storage capacity and water surface area can be analyzed for different dam locations easier than reservoir
surveys method to find the most suitable location for the dam construction