This paper focused on the investigation and mapping of water-related communicable diseases in the Black Sea Catchment area in Turkey by using Geographical Information System (GIS) technology. The official health statistics on Hepatitis-A and Amebic Dysentery from 2000 to 2009 were investigated and evaluated considering the incidence rates. Epidemic, hyper-endemic and endemic thresholds were set regarding the general trends of the incidence rates for both diseases. Time series maps were created to introduce the variation of the incidence rates using GIS. Results interpreting the thematic maps were confirmed with the Mann Whitney U Test statistical analysis and the Spearman correlation analysis. A significant and slight descending trend for Hepatitis A and A Dysentery was detected in the observation period. 16 provinces were assigned as high or low risk-areas regarding the epidemic potential. The downward trend observed could be explained as a result of the wide spread application of best water treatment technologies within the acquisition period for European Union.