This article assesses the surface water quality of the Strîmtori-Firiza reservoir by analyzing 14 physicochemical parameters among 9 metals in 18 sampling points. A series of possible reservoir pollutants were identified, depending on the nature of the pollutants and their loading. The novelty of the paper consists in the broad spectrum of investigations that includes spatial distribution cluster analysis and mathematical modeling. This article presents an innovative method of assessing the distributions of the metal loads as maps of metal distribution that are in accordance with the developed mathematical models that aim to present the pollutant distribution and the degree of correlation between the physicochemical indicators. The clusters were generated using Ward's and Nearest Neighbor methods that are less used in the studies concerning the analysis of water quality. Measures for maintaining the quality of the water reservoir are proposed considering the importance of the reservoir as source for drinking/industrial water.