Public EPA test results
Can you drink Louisville tap water? What EPA records show
EPA system ID CO0107487 · serves Boulder County, CO · about 20,975 people (EPA records)
Here's what EPA has on file for this water system: its testing for newer contaminants like PFAS (UCMR 5), lead testing and violations. It's not a test of your tap, and there's no Water Score here.
Public EPA test results
Louisville City of (EPA CO0107487)
ScoreYourWater.com gives no verdict on your tap water; it shows what the public records say, as of October 14, 2026. For Louisville's main utility, Louisville City of: 2 health-standard violations since July 1, 2021 in EPA records (EPA SDWIS). PFOA and PFOS were not detected at or above EPA's reporting level in EPA's UCMR 5 testing.
What EPA records show for Louisville City of, as of October 14, 2026
2 health-standard violations since July 1, 2021 in EPA records (EPA SDWIS).
Lead: 9 in 10 homes tested came in at or below 0 ppb, at or below EPA's 15 ppb action level (latest EPA result for a testing period that ran on or after July 1, 2021: Jan 1, 2025–Dec 31, 2025). This is one number for the whole water system, from homes the utility tested. It isn't a result for your home.
EPA's UCMR 5 testing looked for 30 contaminants here and found none.
PFOA and PFOS were not detected at or above EPA's reporting level in EPA's UCMR 5 testing.
Source: EPA records (SDWIS, UCMR 5). SDWIS: data as of Oct 14, 2026. EPA UCMR 5 data, samples through June 2026.
Your water bill names your utility.
Does Louisville City of use chloramine?
We didn't find chloramine in Louisville City of's EPA treatment records. That's not a complete list; your utility's annual water quality report says which disinfectant it uses.
What EPA records show for this system
Reported results in EPA records (data as of Oct 14–15, 2026)