Package technology offers an alternative to in-ground conventional treatment systems. Package processes are not altogether different from other treatment processes, although several package plant models contain innovative treatment elements, for instance adsorptive clarifiers. The primary distinction, however, between package plants and custom-designed plants is that package plants are treatment units assembled in a factory, skid mounted, and transported to the site.

These units are most widely used to treat surface water supplies for removal of turbidity, color, and coliform organisms with filtration processes. However, many other treatment technologies are available to small systems as package plants. These technologies or a combination of them can be incorporated into a package plant to provide comprehensive water treatment, including:

disinfection (chlorination, ozonation, ultra-violet radiation)

filtration (bag and cartridge filters, membrane filtration including reverse osmosis or ultra-filtration, slow sand filtration, pressure filtration, diatomaceous earth filtration)

• aeration
• ion exchange
• adsorption (using powdered activated carbon or granular activated carbon)

softening