Ultraviolet (UV) disinfection is one of the most effective and environmentally friendly ways to ensure your water is free from harmful microorganisms. Unlike chemical treatments, UV adds nothing to your water while providing reliable protection against bacteria, viruses, and parasites.
How UV Disinfection Works
UV water treatment uses light at a specific wavelength (254 nanometers) to penetrate microorganisms and damage their DNA. This prevents the pathogens from reproducing, effectively rendering them harmless.
The process is instantaneous—water passes through a stainless steel chamber containing a UV lamp, and microorganisms are inactivated in seconds. No chemicals are added, no taste is imparted, and no harmful byproducts are created.
Pathogen Reduction Rates
When You Need UV Treatment
UV disinfection is essential in certain situations and recommended in others:
Essential Applications
Private wells - Well water isn't treated and can be contaminated by surface water infiltration or nearby septic systems
Positive bacteria tests - If your water has tested positive for coliform bacteria, UV provides ongoing protection
Shallow wells - Wells less than 50 feet deep are more susceptible to contamination
Spring or surface water sources - These are highly susceptible to bacterial contamination
Recommended Applications
Vacation properties - Stagnant water during absence can harbor bacteria
Homes with immunocompromised residents - Extra protection for vulnerable individuals
After other filtration - Final barrier after iron filters or softeners that may introduce bacteria
UV vs. Chemical Disinfection
While chlorination is another option for disinfection, UV offers several advantages:
UV Disinfection
- No chemicals added
- No taste or odor change
- Effective against Cryptosporidium
- No disinfection byproducts
Chlorination
- Provides residual protection
- Lower upfront cost
- -Creates taste/odor
- -Requires chemical handling
System Requirements
For UV treatment to be effective, certain water quality conditions must be met:
Pre-Treatment Often Needed
UV light must reach the pathogens to kill them. High iron, manganese, or turbidity can shield microorganisms. Most wells with bacterial concerns also have other water quality issues that should be addressed with pre-treatment before UV.
Water Quality Requirements
Maintenance Requirements
UV systems are relatively low maintenance, but do require attention:
Annual lamp replacement - UV lamps lose intensity over time and should be replaced yearly
Quartz sleeve cleaning - Clean the protective sleeve every 6-12 months
Pre-filter changes - Replace sediment pre-filter as needed (typically every 6 months)
Modern UV systems include countdown timers or LED indicators that alert you when lamp replacement is due, making maintenance straightforward.