Spatial Evaluation by GIS Mapping and Trend Analysis of Urban Wastewater Amounts in Central Anatolia Region of Turkiye

The wastewater amounts of 13 provinces included in the Central Anatolia Region in Turkiye between 2002 and 2018 were spatially analyzed in the Geography Information Systems (GIS) environment within the scope of this study. Wastewater amounts were spatially evaluated and modeled for each year with the help of the IDW interpolation method. Moreover, the change in wastewater amounts over the years was analyzed using Mann-Kendall, Sperman's Rho, and Sen's Trend Slope Tests. The analyses indicated that while the total amount of wastewater in the Central Anatolia Region was 466279 thousand m3/year in 2002, this amount increased by 31% in 2018 and reached 611275 thousand m3/year. On the other hand, while the amount of treated wastewater was 238779 thousand m3/year in 2002, this rate increased by 123% to 534456 thousand m3/year in 2018. The trend analyses indicated that there was a significant increasing trend in the amounts of treated wastewater in Eskişehir, Çankırı, Kırşehir, Konya, Karaman, Kayseri, Yozgat and Sivas provinces yearly. The change in the total amount of wastewater over the years was analyzed, and it was observed that there was a significant tendency to increase over time in the provinces of Eskişehir, Konya, Karaman, Kayseri, and Sivas.