Corrosion problems having to do with drinking water distribution systems are related to many processes and factors and two of them are ionic acidity and carbon dioxide, which were considered in this work. The corrosion character of water is determined by the corrosion indexes of Langelier, Ryznar, Larson, and Mojmir. The results show that pipes made of different materials, such as plastics or metals, are affected by corrosion, causing manganese to be deposited on materials and dissolved in water. The deterioration of the materials, the degree of corrosion, and the deposited corrosion products were determined by X-ray diffraction and Scanning Electron Microscopy. High levels of manganese and nitrate ions in water may cause serious damage to the health of consumers of water. Three wells were examined, one of them presented a high content of manganese; the others had high levels of nitrate ions, which increased the acidity of the water and, therefore, the amount of corrosion of the materials in the distribution systems. ► Corrosion of distribution systems affects the quality of drinking water. ► Corrosion in water distribution systems is related to acidity and carbon dioxide. ► Pipes are corroded and manganese is deposited on pipes and dissolved in water. ► The deterioration of the pipes and the corrosion products were determined. ► Nitrate ions increase the acidity of water in the wells.