Water treatment systems and methods are provided to beneficially use the concentrate stream for other, non-potable, use. Embodiments of the invention use the distribution pressure to drive the membrane process and are configured in line with household plumbing so the concentrate is directed through the treatment system but bypassing the treatment mechanism to other uses in the building. In embodiments of this system, only the purified water that is needed for potable consumption is extracted from the water with the rest proceeding to its intended destination at the same pressure.