Public water system record
Yankton
Serves Yankton, Yankton County, SD · 15,411 people served
Federal records show 4 health-based violations and no monitoring/reporting issues for Yankton in the last ten years. The most serious issue in this window was a resolved Total Trihalomethanes (TTHMs) violation.
System profile
- Health-based violations, last 10 years
- 4
- Resolved
- 4
- Unresolved
- 0
- Any acute record
- No
- Monitoring issues, last 10 years
- 0
Key facts
- Yankton draws water from 1 well.
- Highest measured level in the last 10 years: Total Trihalomethanes (TTHMs), 0.104 mg/L, federal limit 0.08 mg/L (1.3 times the limit), 2019.
- Most recent formal enforcement: compliance order (no penalty) by South Dakota, March 2009.
- Record on file since 1976, with 16 health-based violations before October 19, 2016.
- Lead pipe inventory: 0 lead and 5,730 unknown out of 5,730 service lines.
Check whether Yankton serves your address
Health-based violations
Since October 2016Violation data reflects EPA records through March 2026. For the most current status, visit the EPA ECHO database.
| Contaminant | Rule family | Start date | Status | Acute |
|---|---|---|---|---|
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.099 mg/L, federal limit 0.08 mg/L (1.2 times the limit)
|
220 | Jan 1, 2020 | Resolved | No |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.104 mg/L, federal limit 0.08 mg/L (1.3 times the limit)
|
220 | Oct 1, 2019 | Resolved | No |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.099 mg/L, federal limit 0.08 mg/L (1.2 times the limit)
|
220 | Jul 1, 2019 | Resolved | No |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.099 mg/L, federal limit 0.08 mg/L (1.2 times the limit)
|
220 | Apr 1, 2019 | Resolved | No |
Full record since 1976
EPA's records for Yankton go back to 1976. Before October 19, 2016 they list 16 health-based violations (16 resolved) and 12 monitoring or reporting violations.
| Violations that began in | Health-based | Monitoring and reporting |
|---|---|---|
| 1970s | 0 | 2 |
| 1990s | 2 | 2 |
| 2000s | 11 | 7 |
| 2010 to October 18, 2016 | 3 | 1 |
| October 19, 2016 to 2019 | 3 | 0 |
| 2020s | 1 | 0 |
Most recent health-based violation before October 19, 2016: Total Trihalomethanes (TTHMs), began April 2016, Resolved.
Show all 16 health-based violations before October 19, 2016
| Contaminant | Start date | Status |
|---|---|---|
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.081 mg/L, federal limit 0.08 mg/L (at or just above the limit)
|
Apr 1, 2016 | Resolved |
|
Stage 1 Disinfection Byproducts Rule
Treatment technique failure
|
Feb 1, 2011 | Resolved |
|
Stage 1 Disinfection Byproducts Rule
Treatment technique failure
|
Feb 1, 2010 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.088 mg/L, federal limit 0.08 mg/L (1.1 times the limit)
|
Jan 1, 2009 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.088 mg/L, federal limit 0.08 mg/L (1.1 times the limit)
|
Oct 1, 2008 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
|
Jul 1, 2008 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
|
Apr 1, 2008 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
|
Jan 1, 2008 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
|
Oct 1, 2007 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
|
Jul 1, 2007 | Resolved |
|
Pentachlorophenol
Contaminant limit exceeded
|
Jan 1, 2007 | Resolved |
|
Pentachlorophenol
Contaminant limit exceeded
|
Oct 1, 2006 | Resolved |
|
Pentachlorophenol
Contaminant limit exceeded
|
Jul 1, 2006 | Resolved |
|
Pentachlorophenol
Contaminant limit exceeded
|
Apr 1, 2006 | Resolved |
|
Surface Water Treatment Rule
Treatment technique failure
|
Feb 1, 1997 | Resolved |
|
Surface Water Treatment Rule
Treatment technique failure
|
Mar 1, 1994 | Resolved |
Enforcement actions
South Dakota regulators took 1 formal enforcement action against Yankton in 2009, filed as 7 records in EPA's data. The most recent was a compliance order (no penalty) in March 2009.
| Date | By | Action | Violations covered |
|---|---|---|---|
| Mar 18, 2009 | South Dakota | Compliance order (no penalty) | 7 violations (7 health-based): Total Trihalomethanes (TTHMs) |
What the violations mean
Total Trihalomethanes (TTHMs)
4 incidentsDisinfection byproduct levels exceeded the federal limit
Long-term TTHM exposure may increase bladder cancer risk
Where the water comes from
Yankton draws water from 1 well.
Annual water quality report
Yankton must give its customers an annual water quality report (Consumer Confidence Report) by July 1, with the levels its tests found in the previous year.
Systems serving 10,000 or more people must mail or deliver the report to every customer, and from 2027 they must send it twice a year.
Find a posted report with EPA's Consumer Confidence Report search
Testing your own water
To test the water at your tap, or a private well this record does not cover, use a laboratory certified for drinking water by South Dakota.
Certified drinking water labs by state EPA guidance for private wells