- EPA's UCMR 5 testing looked for 30 contaminants here and found 1.
- Lithium: found in 2 of 2 samples, average 40 µg/L, highest 69 µg/L (EPA UCMR 5 testing, Jul 2023–Jan 2024)
- 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, 2024–Dec 31, 2024). This is one number for the whole water system, from homes the utility tested. It isn't a result for your home.
Public EPA test results
Can you drink Yankton tap water? What EPA records show
EPA system ID SD4600423 · serves Yankton, SD · about 15,411 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
Yankton (EPA SD4600423)
EPA data as of October 14, 2026. For Yankton's main utility, Yankton: We found no health-standard violations in EPA's records for this system (SD4600423) since July 1, 2021, as of October 14, 2026. PFOA and PFOS were not detected at or above EPA's reporting level in EPA's UCMR 5 testing. This is public data, not a test of your tap.
What EPA records show for Yankton, as of October 14, 2026
We found no health-standard violations in EPA's records for this system (SD4600423) since July 1, 2021, as of October 14, 2026.
Source: EPA ECHO record for Yankton (SDWIS). Data as of October 14, 2026.
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, 2024–Dec 31, 2024). 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 1.
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 Yankton use chloramine?
We didn't find chloramine in Yankton's EPA treatment records. That's not a complete list; your utility's annual water quality report says which disinfectant it uses.