UV is worth it when testing or source risk justifies ongoing microbiological disinfection and the water is properly prefiltered. It is not a substitute for treatment of chemical contaminants.
When UV adds real value
Private wells can be vulnerable to microbial contamination after flooding, well work, surface intrusion or other failures. A properly sized point-of-entry UV system adds continuous disinfection without adding chemicals.
When UV is the wrong purchase
CDC notes UV does not remove chemicals. If nitrate, arsenic, PFAS, hardness or iron is the problem, another treatment technology is required.
Ownership cost is predictable
UV typically requires electricity, annual lamp-unit replacement and periodic quartz-sleeve cleaning. Those recurring costs are easier to forecast than many media-based systems.
Testing still matters
CDC recommends testing private wells and confirming that the chosen treatment addresses the specific germ or chemical of concern.