A method for treating water including intaking a first amount of water into a plurality of treatment blocks, treating the first amount of water, outputting aqueous treated water streams from each of the plurality of treatment blocks, separating the aqueous treated water streams from each of the plurality of treatment blocks into aqueous permeate streams and concentrate reject streams, monitoring each of the aqueous permeate streams, controlling the operation of at least one of the plurality of treatment blocks based on predefined water-characteristic tolerances that fall within a predetermined concentration range based on the different qualities of the aqueous permeate streams, combining the aqueous permeate streams of at least two of the plurality of treatment blocks based on the identified characteristics and the predefined water-characteristic tolerances, and outputting the product water stream and the at least one concentrate reject stream.