The size of a desalination storage reservoir varies widely depending on the scale of the plant, the population served, and how much backup supply is required. In municipal systems, reservoirs are often designed to hold at least one day’s worth of production, which can range from several thousand gallons for small facilities to tens or even hundreds of millions of gallons for large coastal plants supplying major cities.
For example, a plant producing a million gallons per day might have a reservoir of similar capacity to ensure continuous supply if the plant is shut down for maintenance or if demand temporarily exceeds production. Smaller community or industrial desalination units may use reservoirs sized in 50 to 100 thousand gallons, often in the form of storage tanks rather than large open basins.
