International Conference on Global Practice of Multidisciplinary Scientific Studies-III, Girne, Cyprus (Kktc), 15 November 2022, pp.1667-1678
As part of the Water Supply Project, Geçitköy Dam was built near Girne to store the water brought from Turkey by submarine for 80 km to meet the water needs of Northern Cyprus. This reservoir allows irrigation on approximately 5000 hectares of land and use of drinking water. In addition, this water source and its surroundings are used daily by visitors due to the scenery it has. The water resources in Northern Cyprus are decreasing every year due to global climate change, less precipitation and excessive use. This situation increases the importance of existing water collection areas. Therefore, in order to produce efficient water policies, it is necessary to determine the time-dependent changes of existing water resources and to take necessary measures in this context. This study aims to determine the change of water surface area in Geçitköy reservoir between 2013-2020 using Landsat images. Automated Water Extraction Index (AWEI) was used to automatically extract the water surface area from the images. This index was chosen because it gives high accuracy in wetlands, including shade and dark surfaces, which other classification methods often fail to classify correctly. After the radiometric correction process was applied to the Landsat images of the years 2013-2015-2020, firstly the lake shoreline was created manually and used as reference data for accuracy assessment. Then, the water surface area was automatically determined and compared by applying AWEI to the images of three different years. According to the results obtained, the water area in the Geçitköy reservoir was 18.44 ha in 2013. In 2015, which is the construction phase of the dam, the water area was determined as 14.28 ha. According to the images of 2020, the water surface area has been determined as 64.64 ha. The accuracy analysis results are 90%, 85% and 91%, respectively. In this study, the water surface area of Geçitköy Reservoir for different dates was determined with high accuracy from satellite images using AWEI. The results show that the water in the reservoir increased significantly after the Northern Cyprus Water Supply Project.