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Water Treatment Technologies for Private Water Systems

A wide variety of water treatment systems and devices exist that remove or reduce unwanted chemicals and/or microorganisms through disinfection, physical filtration, adsorptive filtration, oxidation/reduction and chemical exchange reactions in order to make water potable or improve the aesthetics of the water.

Best available technologies (BATs) describe water treatment methods that are consider best at removing different kinds of specific chemicals and contaminants from water being used for potable purposes. Some chemicals can be removed or reduced by several water treatment methods that are all considered BATs. Many treatment methods and devices are used in combinations to improve the over-all treatment capability. Some water quality issues will require that different treatment methods be used in combination to get adequate contaminant reduction.

Permit Requirements

Whole-house water treatment devices installed on an existing private water system for continuous disinfection and to treat for health related contaminants such as arsenic, nitrates and VOCs are required to be installed under an alteration permit obtained from the local health department. These treatment systems must also be installed by a private water system contractor registered with the Ohio Department of Health (see link).

Water treatment systems installed to treat aesthetic conditions such as hardness, high sulfur, or high iron do not require a permit to be installed and are not required to be installed by a registered private water systems contractor.

Any treatment system installed at the POU (such as at one sink), do not require a permit or a registered private water system contractor for the installation.

Below are very brief descriptions of some of the more common water treatment methods. This list is not all-inclusive of all possible types of home water treatment.  There are also new products continually being developed for home water treatment.

Information on technologies which are effective at removing specific contaminants:

Nitrate        Arsenic

Other Contacts for Water Treatment Information

 Water Quality Association (WQA) they are the professional organization for water treatment dealers.

ANSI/ NSF certifies water treatment products under product standards 53 (filters), 55 (UV devices), 60 (chemicals for use in water) and 61 (water device components and process media). To search certified product listings


Types of Water Treatment

Consult with the Local Health District and Private Water Systems Contractor about the appropriate treatment for your water. 

Water treatment can be whole-house, also called point of entry (POE) or at the point-of-use (POU) depending on the needs of the household. Whole-house (POE) treatment is installed at the pressure tank and treated water goes to all spigots and water outlets in the house. POU treatment is providing treatment to only one particular spigot location.

           Type Whole House or Point of Entry (POE)  Point of Use (POU) 
  Filtration   X 
  Chlorine Continuous Disinfection  X  
  Iodine Continuous Disinfection  X  
  UV Continuous Disinfection   X  
  Ozone Continuous Disinfection   X   
  Granular Activated Carbon (GAC)   X 
  Reverse Osmosis   X 
  Ion Exchange   X   
  Aeration   X   

Page updated: 05/30/2018