Get to the Point

Point of use v. point of entry water treatment devices

 Cori Lamont  |    October 08, 2018
Get to the Point

Generally, when a property has a private well, a buyer includes both a well inspection and a well water testing contingency. The challenge for a number of buyers, sellers and agents is trying to explain or understand what happens when the well water test comes back with an unsafe level of a substance, which requires the installation of a water treatment device. More specifically, the confusion occurs as to the location of the water treatment device: is it installed at the point of entry (POE) or at the point of use (POU)?

What is a POE and what is a POU? 

  • POE: POE treats all water prior to entering the house. POE devices are installed where the water lines enter the house.
  • POU: POU treats water for an individual source of water. POU devices are installed ahead of a tap, faucet or other item dedicated to dispense water. 

Where is a POE or POU installed? 

It depends. The location of where the water treatment device will be installed will vary depending on the contingency language. Since the majority of transactions in the state do not include a private well, the state-approved (WB) form does not include well contingencies such as a well water testing contingency. Therefore, many company or local board addenda include provisions that are more common in their marketplace such as a private on-site wastewater treatment system (POWTS), well inspection or well water testing contingency. For licensees who do not have a local board or company addenda to utilize, the WRA created Addendum B. 

When agents are involved in a transaction, they should carefully review the addenda if they are unfamiliar with the well water testing contingency because most addenda provide that if an unsafe level of a substance, such as nitrates, is found in the well water, the seller has the right to cure by installing some sort of water treatment device. However, since each addendum may handle this differently, agents must carefully review the addendum language being incorporated into the offer to ensure they understand how the contingency provides for the seller to remediate the issue. Note that the WRA’s Addendum B allows the parties to agree on whether the POE or POU is appropriate for the seller to cure.

For instance, if an agent is unfamiliar with the contingency language, the agent should review the contingency to determine:

  • Whether the seller has the right to cure.
  • Which party has the ability to choose the type of device — whether POE or POU.
  • Whether the contingency pre\determines that the seller will cure through the installation of a specific type of water treatment device approved by the Department of Safety and Professional Services. 

Are POE and POU devices the same cost? 

Generally, no. A POU device is typically more affordable compared to POE because of the location and extra level of installation required for POE as well as additional costs in plumbing as well as the cost of installation. 

Is a POE or POU used for all types of unsafe levels of substances found in well water? 

No. While a POE or POU can address some issues and generally provide a better quality of drinking water, there are certain substances that must be addressed in a different way. For example, lead in water cannot be removed by simply installing a POE or POU water treatment device. For example, the Environmental Protection Agency (EPA) indicates that in order to address microbial issues, water must be boiled; a filtration system would not remove the bacteria in that situation. Alternately, the EPA states that simply boiling water with nitrates will not reduce nitrates in the water and that a filtration systems such as a POE or a POU must be utilized to address the concern. As a further example, boiling water contaminated with lead actually increases the lead concentration.

What are the different types of POE and POU devices? 

POE and POU water treatment devices may include filtration, ion exchange and reverse osmosis. The EPA provides the following information regarding the different types of POE and POU devices: 

Activated carbon filter: Activated carbon filters adsorb organic contaminants that cause taste and odor problems. Depending on the design, some units can remove chlorination byproducts, some cleaning solvents and pesticides. Carbon canisters must be replaced periodically to maintain the effectiveness of the unit. Activated carbon filters are efficient in removing metals such as lead and copper if they are designed to absorb or remove lead. 

Ion exchange unit: Because ion exchange units can be used to remove minerals from water, particularly calcium and magnesium, they are sold for water softening. Some ion exchange softening units remove radium and barium from water. Ion exchange systems that employ activated alumina are used to remove fluoride and arsenate from water. These units must be regenerated periodically with salt. 

Reverse osmosis (RO) treatment unit: “RO” units, as they are often called, generally remove a more diverse list of contaminants than other systems. These units can remove nitrates, sodium, other dissolved inorganics and organic compounds. 

The unit descriptions above are from the EPA’s online water guide, “Water on Tap: What you need to know,” at

Again, it is imperative for agents to review and parties to understand what happens under the well water testing contingency if unsafe substance levels are found in the well water. Does the seller have the right to cure? Does the buyer have the right to dictate a POE or a POU? Does the seller get to decide if a POE or a POU system is installed? While a contingency provides for a POE, does a device only have to go on the kitchen faucets only or all faucets? Look to the contingency to find the answer, and if you don’t see the answer add language to the additional provisions or in a counter-offer depending on the circumstance to remove any doubt that if the seller has the right to cure, how the seller may cure and specifically how.

Cori Lamont is Director of Corporate and Regulatory Affairs for the WRA.

Copyright 1998 - 2024 Wisconsin REALTORS® Association. All rights reserved.

Privacy Policy   |   Terms of Use   |   Accessibility   |   Real Estate Continuing Education