The main microbiological risks of storing desalinated water come from the potential growth of bacteria, algae, or biofilms if conditions are not properly controlled. Because desalinated water is low in minerals and nutrients, it does not naturally encourage microbial growth, but contamination can still occur from the environment, reservoir surfaces, or inflow points.
Without sufficient disinfection, bacteria can multiply in stagnant areas of a reservoir, leading to waterborne pathogens or secondary problems such as biofilm formation inside pipes. Algae growth, more common in uncovered reservoirs exposed to sunlight, can also support microbial activity and produce by-products that affect water taste and odor. Another concern is the gradual decline of chlorine or chloramine residuals during storage. If disinfectant levels fall too low, the risk of microbial regrowth increases, especially in warm climates.
