In the present invention, a potable water treatment system and apparatus for purifying and treating potable water that is being transferred from a potable water source to a number of potable water user(s) via a potable water line is presented. Said potable water purification and treatment system and apparatus has a filter capable of filtering the potable water to an NTU of less than 0.10, removing TOC and disinfection by-products, as well as a chemical feed system which comprises a measuring device for measuring at least one of: the potable water flow and the potable water quality, at least one proportioning device for determining any amount(s) of chemical additives utilizing input(s) from the measuring device(s) and at least one chemical feed pump to transfer at least one chemical additive to the potable water, wherein at least a disinfectant is added to the potable water downstream of filtration. In addition to disinfectant addition, said potable water purification and treatment system and apparatus has the capability to add at least one of a: chelant, dispersant, oxidizer, metal coagulant, buffer and/or any combination therein. While the measuring device, proportioning device and/or chemical pump can be one unit, each can be separate or combined in any combination providing that the required chemical(s) and amount of chemical(s) is pumped or successfully transferred to the potable water. The method of operation of the potable water treatment system and apparatus is also presented.