Public water system record
Cheyenne
Serves an area of Roger Mills County, OK that includes Cheyenne · 778 people served
Federal records show 24 health-based violations and 19 monitoring/reporting issues for Cheyenne in the last ten years. The most serious issue in this window was a Total Trihalomethanes (TTHMs) violation that EPA lists as archived, not resolved.
System profile
Source water
Surface water
ZIP
73628
EPA system ID
OK1010803
- Health-based violations, last 10 years
- 24
- Resolved
- 20
- Unresolved
- 0
- Archived by EPA
- 4
- Any acute record
- Yes
- Monitoring issues, last 10 years
- 19
Key facts
- Cheyenne draws water from 1 surface water intake.
- Highest measured level in the last 10 years: Total Trihalomethanes (TTHMs), 0.12 mg/L, federal limit 0.08 mg/L (1.5 times the limit), 2017.
- Most recent formal enforcement: compliance order (no penalty) by Oklahoma, November 2025.
- Record on file since 1994, with 40 health-based violations before October 19, 2016.
- Lead pipe inventory: 0 lead and 295 unknown out of 498 service lines.
Check whether Cheyenne 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 0.084 mg/L, federal limit 0.08 mg/L (1.1 times the limit)
|
220 | Jul 1, 2025 |
Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
|
No |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.085 mg/L, federal limit 0.08 mg/L (1.1 times the limit)
|
220 | Apr 1, 2025 |
Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
|
No |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.089 mg/L, federal limit 0.08 mg/L (1.1 times the limit)
|
220 | Jan 1, 2025 |
Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
|
No |
|
LEAD AND COPPER RULE REVISIONS
Treatment technique failure
|
350 | Oct 17, 2024 | Resolved | No |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.088 mg/L, federal limit 0.08 mg/L (1.1 times the limit)
|
220 | Oct 1, 2024 |
Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
|
No |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.082 mg/L, federal limit 0.08 mg/L (at or just above the limit)
|
220 | Jul 1, 2020 | Resolved | No |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.101 mg/L, federal limit 0.08 mg/L (1.3 times the limit)
|
220 | Apr 1, 2020 | Resolved | No |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.098 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 0.098 mg/L, federal limit 0.08 mg/L (1.2 times the limit)
|
220 | Oct 1, 2019 | Resolved | No |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.096 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 0.1 mg/L, federal limit 0.08 mg/L (1.3 times the limit)
|
220 | Apr 1, 2019 | Resolved | No |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.082 mg/L, federal limit 0.08 mg/L (at or just above the limit)
|
220 | Apr 1, 2019 | Resolved | No |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.098 mg/L, federal limit 0.08 mg/L (1.2 times the limit)
|
220 | Jan 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 | Oct 1, 2018 | Resolved | No |
|
Surface Water Treatment Rule
Treatment technique failure
|
120 | Oct 1, 2018 | Resolved | No |
|
Interim Enhanced Surface Water Treatment Rule
Treatment technique failure
|
120 | Oct 1, 2018 | Resolved | Yes |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.096 mg/L, federal limit 0.08 mg/L (1.2 times the limit)
|
220 | Jul 1, 2018 | Resolved | No |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.087 mg/L, federal limit 0.08 mg/L (1.1 times the limit)
|
220 | Apr 1, 2018 | Resolved | No |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.096 mg/L, federal limit 0.08 mg/L (1.2 times the limit)
|
220 | Jan 1, 2018 | 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 | Oct 1, 2017 | Resolved | No |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.115 mg/L, federal limit 0.08 mg/L (1.4 times the limit)
|
220 | Jul 1, 2017 | Resolved | No |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.12 mg/L, federal limit 0.08 mg/L (1.5 times the limit)
|
220 | Apr 1, 2017 | Resolved | No |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.087 mg/L, federal limit 0.08 mg/L (1.1 times the limit)
|
220 | Jan 1, 2017 | Resolved | No |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.092 mg/L, federal limit 0.08 mg/L (1.2 times the limit)
|
220 | Oct 1, 2016 | Resolved | No |
Monitoring and reporting issues
Since October 2016Missed tests or reports, not contaminants found above a limit.
| Issue | Start date | Status |
|---|---|---|
|
Revised Total Coliform Rule
Monitoring violation
|
Nov 1, 2025 |
Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
|
|
CARBON, TOTAL
Monitoring and reporting
|
Nov 1, 2025 |
Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
|
|
CARBON, TOTAL
Monitoring and reporting
|
Nov 1, 2025 |
Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
|
|
Chlorine
Monitoring and reporting
|
Nov 1, 2025 |
Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
|
|
Total Trihalomethanes (TTHMs)
Monitoring and reporting
|
Dec 30, 2024 | Resolved |
|
LEAD AND COPPER RULE REVISIONS
RPT
|
Oct 17, 2024 | Resolved |
|
Revised Total Coliform Rule
Monitoring violation
|
Feb 1, 2024 | Resolved |
|
CARBON, TOTAL
Monitoring and reporting
|
Jan 1, 2024 | Resolved |
|
CARBON, TOTAL
Monitoring and reporting
|
Jan 1, 2024 | Resolved |
|
Chlorine
Monitoring and reporting
|
Jan 1, 2024 | Resolved |
|
CARBON, TOTAL
Monitoring and reporting
|
Jul 1, 2023 | Resolved |
|
CARBON, TOTAL
Monitoring and reporting
|
Jul 1, 2023 | Resolved |
|
Haloacetic Acids (HAA5)
Monitoring and reporting
|
May 1, 2023 | Resolved |
|
Total Trihalomethanes (TTHMs)
Monitoring and reporting
|
May 1, 2023 | Resolved |
|
Revised Total Coliform Rule
Monitoring violation
|
May 1, 2023 | Resolved |
|
CARBON, TOTAL
Monitoring and reporting
|
Jul 1, 2019 |
Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
|
|
CARBON, TOTAL
Monitoring and reporting
|
Jul 1, 2019 |
Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
|
|
CARBON, TOTAL
Monitoring and reporting
|
Jul 1, 2017 | Resolved |
|
CARBON, TOTAL
Monitoring and reporting
|
Oct 1, 2016 | Resolved |
Full record since 1994
EPA's records for Cheyenne go back to 1994. Before October 19, 2016 they list 40 health-based violations (39 resolved, 1 archived by EPA without a recorded fix) and 25 monitoring or reporting violations.
| Violations that began in | Health-based | Monitoring and reporting |
|---|---|---|
| 1990s | 5 | 0 |
| 2000s | 17 | 20 |
| 2010 to October 18, 2016 | 18 | 5 |
| October 19, 2016 to 2019 | 15 | 3 |
| 2020s | 8 | 15 |
Most recent health-based violation before October 19, 2016: Total Trihalomethanes (TTHMs), began October 2016, Resolved.
Show all 40 health-based violations before October 19, 2016
| Contaminant | Start date | Status |
|---|---|---|
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.092 mg/L, federal limit 0.08 mg/L (1.2 times the limit)
|
Oct 1, 2016 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.118 mg/L, federal limit 0.08 mg/L (1.5 times the limit)
|
Jul 1, 2016 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.123 mg/L, federal limit 0.08 mg/L (1.5 times the limit)
|
Apr 1, 2016 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.121 mg/L, federal limit 0.08 mg/L (1.5 times the limit)
|
Jan 1, 2016 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.118 mg/L, federal limit 0.08 mg/L (1.5 times the limit)
|
Oct 1, 2015 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.113 mg/L, federal limit 0.08 mg/L (1.4 times the limit)
|
Jul 1, 2015 | Resolved |
|
Interim Enhanced Surface Water Treatment Rule (acute)
Treatment technique failure
|
Jul 1, 2015 | Resolved |
|
Interim Enhanced Surface Water Treatment Rule (acute)
Treatment technique failure
|
Jun 1, 2015 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.082 mg/L, federal limit 0.08 mg/L (at or just above the limit)
|
Apr 1, 2015 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.105 mg/L, federal limit 0.08 mg/L (1.3 times the limit)
|
Jan 1, 2015 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.094 mg/L, federal limit 0.08 mg/L (1.2 times the limit)
|
Oct 1, 2014 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.089 mg/L, federal limit 0.08 mg/L (1.1 times the limit)
|
Jul 1, 2014 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.099 mg/L, federal limit 0.08 mg/L (1.2 times the limit)
|
Apr 1, 2013 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.101 mg/L, federal limit 0.08 mg/L (1.3 times the limit)
|
Jan 1, 2013 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.091 mg/L, federal limit 0.08 mg/L (1.1 times the limit)
|
Oct 1, 2012 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.086 mg/L, federal limit 0.08 mg/L (1.1 times the limit)
|
Jul 1, 2012 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.092 mg/L, federal limit 0.08 mg/L (1.2 times the limit)
|
Apr 1, 2010 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.094 mg/L, federal limit 0.08 mg/L (1.2 times the limit)
|
Jan 1, 2010 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.091 mg/L, federal limit 0.08 mg/L (1.1 times the limit)
|
Oct 1, 2008 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.089 mg/L, federal limit 0.08 mg/L (1.1 times the limit)
|
Jul 1, 2008 | Resolved |
|
CARBON, TOTAL
Treatment technique failure
|
Apr 1, 2007 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.099 mg/L, federal limit 0.08 mg/L (1.2 times the limit)
|
Jan 1, 2007 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.104 mg/L, federal limit 0.08 mg/L (1.3 times the limit)
|
Oct 1, 2006 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.094 mg/L, federal limit 0.08 mg/L (1.2 times the limit)
|
Jul 1, 2006 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.092 mg/L, federal limit 0.08 mg/L (1.2 times the limit)
|
Apr 1, 2006 | Resolved |
|
CARBON, TOTAL
Treatment technique failure
|
Apr 1, 2006 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.095 mg/L, federal limit 0.08 mg/L (1.2 times the limit)
|
Jan 1, 2006 | Resolved |
|
CARBON, TOTAL
Treatment technique failure
|
Jan 1, 2006 | Resolved |
|
CARBON, TOTAL
Treatment technique failure
|
Oct 1, 2005 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
|
Oct 1, 2005 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
|
Jul 1, 2005 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
|
Apr 1, 2005 | Resolved |
|
Interim Enhanced Surface Water Treatment Rule (acute)
Treatment technique failure
|
Mar 1, 2005 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
|
Jan 1, 2005 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
|
Oct 1, 2004 | Resolved |
|
Surface Water Treatment Rule
Treatment technique failure
|
Jan 1, 1996 | Resolved |
|
Surface Water Treatment Rule
Treatment technique failure
|
Aug 1, 1995 | Resolved |
|
Surface Water Treatment Rule
Treatment technique failure
|
Jun 1, 1995 | Resolved |
|
Surface Water Treatment Rule
Treatment technique failure
|
Jul 1, 1994 | Archived |
|
Surface Water Treatment Rule
Treatment technique failure
|
Jun 1, 1994 | Resolved |
Enforcement actions
Oklahoma regulators took 36 formal enforcement actions against Cheyenne between 1995 and 2025, filed as 37 records in EPA's data. The most recent was a compliance order (no penalty) in November 2025.
| Date | By | Action | Violations covered |
|---|---|---|---|
| Nov 12, 2025 | Oklahoma | Compliance order (no penalty) | 1 violation (1 health-based): Total Trihalomethanes (TTHMs) |
| Aug 7, 2025 | Oklahoma | Compliance order (no penalty) | 1 violation (1 health-based): Total Trihalomethanes (TTHMs) |
| Apr 3, 2025 | Oklahoma | Compliance order (no penalty) | 1 violation (1 health-based): Total Trihalomethanes (TTHMs) |
| Jan 7, 2025 | Oklahoma | Compliance order (no penalty) | 1 violation (1 health-based): Total Trihalomethanes (TTHMs) |
| Mar 11, 2020 | Oklahoma | Compliance order with a penalty | 26 violations (26 health-based): Total Trihalomethanes (TTHMs) |
| Dec 14, 2018 | Oklahoma | Compliance order (no penalty) | 2 violations (2 health-based): Interim Enhanced Surface Water Treatment Rule, Surface Water Treatment Rule |
| Jun 23, 2016 | Oklahoma | Compliance order with a penalty | 24 violations (24 health-based): Total Trihalomethanes (TTHMs) |
| Mar 9, 2016 | Oklahoma | Compliance order with a penalty | 1 violation (1 health-based): Total Trihalomethanes (TTHMs) |
| Dec 2, 2015 | Oklahoma | Compliance order with a penalty | 1 violation (1 health-based): Total Trihalomethanes (TTHMs) |
| Sep 21, 2015 | Oklahoma | Compliance order with a penalty | 1 violation (1 health-based): Interim Enhanced Surface Water Treatment Rule |
| Sep 9, 2015 | Oklahoma | Compliance order with a penalty | 1 violation (1 health-based): Total Trihalomethanes (TTHMs) |
| Aug 19, 2015 | Oklahoma | Compliance order with a penalty | 1 violation (1 health-based): Interim Enhanced Surface Water Treatment Rule |
| Jun 9, 2015 | Oklahoma | Compliance order with a penalty | 1 violation (1 health-based): Total Trihalomethanes (TTHMs) |
| Mar 11, 2015 | Oklahoma | Compliance order with a penalty | 1 violation (1 health-based): Total Trihalomethanes (TTHMs) |
| Nov 12, 2014 | Oklahoma | Compliance order with a penalty | 1 violation (1 health-based): Total Trihalomethanes (TTHMs) |
| Jul 11, 2013 | Oklahoma | Compliance order with a penalty | 1 violation (1 health-based): Total Trihalomethanes (TTHMs) |
| May 28, 2013 | Oklahoma | Compliance order with a penalty | 1 violation (1 health-based): Total Trihalomethanes (TTHMs) |
| Dec 6, 2012 | Oklahoma | Compliance order with a penalty | 2 violations (2 health-based): Total Trihalomethanes (TTHMs) |
| May 18, 2010 | Oklahoma | Compliance order with a penalty | 1 violation (1 health-based): Total Trihalomethanes (TTHMs) |
| Feb 12, 2009 | Oklahoma | Compliance order with a penalty | 12 violations: CARBON, TOTAL |
| Mar 25, 2008 | Oklahoma | Compliance order with a penalty | 1 violation (1 health-based): Total Trihalomethanes (TTHMs) |
| Dec 6, 2007 | Oklahoma | Compliance order with a penalty | 1 violation: CARBON, TOTAL |
| Nov 30, 2007 | Oklahoma | Compliance order with a penalty | 1 violation (1 health-based): CARBON, TOTAL |
| Feb 16, 2007 | Oklahoma | Compliance order with a penalty | 1 violation (1 health-based): Total Trihalomethanes (TTHMs) |
| Dec 8, 2006 | Oklahoma | Compliance order with a penalty | 1 violation (1 health-based): Total Trihalomethanes (TTHMs) |
| Oct 5, 2006 | Oklahoma | Compliance order with a penalty | 2 violations (2 health-based): Total Trihalomethanes (TTHMs), CARBON, TOTAL |
| Sep 13, 2006 | Oklahoma | Compliance order with a penalty | 2 violations (2 health-based): CARBON, TOTAL, Total Trihalomethanes (TTHMs) |
| Apr 10, 2006 | Oklahoma | Compliance order with a penalty | 2 violations (2 health-based): CARBON, TOTAL, Total Trihalomethanes (TTHMs) |
| Apr 10, 2006 | Oklahoma | Compliance order (no penalty) | 17 violations (17 health-based): Total Trihalomethanes (TTHMs), CARBON, TOTAL |
| Jan 25, 2006 | Oklahoma | Compliance order with a penalty | 2 violations (2 health-based): Total Trihalomethanes (TTHMs) |
| Nov 10, 2005 | Oklahoma | Compliance order with a penalty | 1 violation (1 health-based): Total Trihalomethanes (TTHMs) |
| May 4, 2005 | Oklahoma | Compliance order with a penalty | 1 violation (1 health-based): Interim Enhanced Surface Water Treatment Rule |
| Apr 15, 2005 | Oklahoma | Compliance order with a penalty | 1 violation (1 health-based): Total Trihalomethanes (TTHMs) |
| Feb 20, 1996 | Oklahoma | Compliance order (no penalty) | 1 violation (1 health-based): Surface Water Treatment Rule |
| Sep 22, 1995 | Oklahoma | Compliance order (no penalty) | 1 violation (1 health-based): Surface Water Treatment Rule |
| Jul 19, 1995 | Oklahoma | Compliance order (no penalty) | 1 violation (1 health-based): Surface Water Treatment Rule |
What the violations mean
Total Trihalomethanes (TTHMs)
21 incidentsDisinfection byproduct levels exceeded the federal limit
Long-term TTHM exposure may increase bladder cancer risk
LEAD AND COPPER RULE REVISIONS
1 incidentThe system did not complete a treatment step or action that the LEAD AND COPPER RULE REVISIONS requires (a treatment technique violation).
The utility had to notify customers about this violation.
Surface Water Treatment Rule
1 incidentThe system did not complete a treatment step or action that the Surface Water Treatment Rule requires (a treatment technique violation).
The utility had to notify customers about this violation.
Interim Enhanced Surface Water Treatment Rule
1 incidentThe system did not meet a filtration or treatment requirement for surface water
Inadequate treatment of surface water can let pathogens such as Cryptosporidium and Giardia through
Where the water comes from
Cheyenne draws water from 1 surface water intake.
Annual water quality report
Cheyenne 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.
Where the state allows it, systems serving fewer than 10,000 people may publish the report in a local newspaper or news site instead of mailing it, and must provide a copy on request.
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 Oklahoma.
Certified drinking water labs by state EPA guidance for private wells