Reservoir water is water stored in reservoirs, commonly intended for purification to drinking-water quality and distribution through the public supply system. For food factories, the quality of incoming reservoir water matters well beyond drinking: it feeds boilers, cooling systems, washing lines, and sometimes food-contact uses, where contamination, hardness, or mineral content could damage equipment, taint products, or compromise safety. Seasonal changes in reservoir water, such as algal blooms or turbidity after storms, are therefore watched by plant water-treatment staff, who adjust treatment to keep process water consistently fit for purpose.