The demand for clean water is growing faster than the ability to supply it, so the proportion of the population that can be served by PDAMs is shrinking. PDAM Tirta Je'ne'berang is authorized to provide society drinking water services that meet the requirements. The laboratory at PDAM Tirta Je'ne'berang is used to measure and examine the quality characteristics used as a determinant of water quality, which include turbidity and the amount of dissolved solids. Water quality tests were performed in a multivariate manner, with the parameters used being normally distributed and correlated with one another. As a result, the MEWMV control chart, which can monitor variability, is used in this study. The water quality characteristics used are turbidity and chlorine, which are determined using the MEWMV control chart, weights ω, λ, and L. According to the findings of the analysis, the most sensitive weights in monitoring water quality variability were ω = 0.8, λ = 0.9, and L = 4.8004, where no data is out of control in either phase, and thus the data has been statistically controlled. The weights ω = 0.8, λ = 0.9 were chosen as the most optimal because they have the smallest difference from the\ value of Tr(Vt) Max with UCL. Environmental factors in the form of natural conditions and human factors, specifically the shift change that affects measurement results, are the factors causing the data to become out of control. The results of the process capability calculation obtained with precision are good, but the accuracy still needs to be improved.