Largest public system
- City of Lexington: TTHM (disinfection byproducts)
- 44 ppb
- As reported (2025); federal limit 80 ppb.
- City of Lexington, 2025
- City of Lexington: HAA5 (disinfection byproducts)
- 40 ppb
- As reported (2025); federal limit 60 ppb.
- City of Lexington, 2025
- City of Lexington: Lead (at sampled homes' taps)
- 0 ppb
- 90th percentile of homes sampled (2024); 0 sampled homes above the action level. The federal action level is 15 ppb.
- City of Lexington, 2025