UV disinfection kills 99.99% of bacteria, viruses, and protozoa without chemicals. Here's how to choose and install the right UV system for your well.
UV disinfection is the most effective, lowest-maintenance method for eliminating biological contamination from well water. It kills 99.99% of pathogens including bacteria, viruses, Giardia, and Cryptosporidium without adding chemicals or affecting taste. If you have a private well, UV should be part of your treatment stack.
A UV lamp (typically producing light at 254nm wavelength) exposes water to ultraviolet radiation as it flows through a chamber. UV light penetrates the cell walls of microorganisms and disrupts their DNA, preventing them from reproducing. The pathogens are neutralized — they cannot infect you even though they remain in the water.
UV kills organisms but does not remove them, nor does it address chemical contamination. UV must be installed after filtration — clear water is essential for UV effectiveness. Iron particles, sediment, or turbidity block UV light and reduce effectiveness. The correct order is always: sediment filter → main treatment → UV → whole house.
| 5 GPM (Point of Use) | Single faucet or small household |
| 10 GPM | Typical 1–3 bathroom home |
| 15 GPM | 3–5 bathroom home |
| 20+ GPM | Large households or high demand |
Size slightly above your peak demand. Running a UV system at maximum flow reduces UV exposure time and effectiveness.
UV lamps degrade over time — they may still emit visible light but UV output drops. Replace annually regardless of whether the lamp appears burned out. Most UV systems have an alarm or indicator for lamp replacement.
| UV lamp | Replace every 12 months |
| Quartz sleeve | Inspect annually, replace every 2–3 years |
| Annual lamp cost | $50–$80 depending on system |