Adding a water filter when installing a UV Light.

From a home inspector's perspective, a water filter combined with a UV (ultraviolet) light treatment system is a common and effective setup for treating well water due to the following reasons:

1. Comprehensive Water Treatment

• Water filters remove sediment, particulates, and some chemical contaminants (like iron, manganese, or chlorine).

• UV lights disinfect the water by using ultraviolet radiation to kill or inactivate bacteria, viruses, and other pathogens, including E. coli, Giardia, and Cryptosporidium, which are common in untreated groundwater.

2. UV Light Requires Clear Water to Work Effectively

• UV disinfection is only effective when the water is clear. Any turbidity (cloudiness) or particulates in the water can:

  • Block or scatter the UV rays.

  • Provide shelter for microbes from the UV exposure.

• A pre-filter (often a sediment or carbon filter) is installed before the UV system to ensure the water is clean enough for the UV light to work properly.

3. Typical Well Water Concerns

• Private wells often draw water from untreated underground sources, which can:

  • Contain naturally occurring microorganisms.

  • Be contaminated by surface runoff, animal waste, or septic systems, particularly after heavy rains or floods.

• A dual system ensures both physical impurities and biological contaminants are addressed.

4. Health and Safety

• The combined system provides peace of mind to homeowners by significantly reducing the risk of waterborne illnesses.

• Home inspectors flag potential health risks, and an installed and properly maintained UV + filter system is a major plus for a property with well water.

5. Code and Insurance Considerations

• In some areas, water treatment systems may be required by local health departments, especially when a well has tested positive for bacteria.

• Some lenders or insurance companies may also require a functioning treatment system before approving a mortgage or policy.

Summary

From a home inspection standpoint, the presence of both a water filter and UV light in a well water system indicates a proactive approach to water safety and quality. The filter ensures optimal UV performance, and the UV light ensures microbial safety — a combination that helps protect homeowner health and property value.