Public water system record
Maryville PWS
Serves Maryville, Nodaway County, MO · 10,775 people served
Federal records show 4 health-based violations and 8 monitoring/reporting issues for Maryville PWS in the last ten years. The most serious issue in this window was a Interim Enhanced Surface Water Treatment Rule violation that EPA lists as archived, not resolved.
System profile
- Health-based violations, last 10 years
- 4
- Resolved
- 3
- Unresolved
- 0
- Archived by EPA
- 1
- Any acute record
- Yes
- Monitoring issues, last 10 years
- 8
Key facts
- Maryville PWS draws water from 2 surface water intakes and 2 reservoirs.
- Highest measured level in the last 10 years: Chlorite, 1.3 mg/L, federal limit 1 mg/L (1.3 times the limit), 2024.
- Most recent enforcement action: boil water order by Missouri, June 2002.
- Record on file since 1983, with 16 health-based violations before October 19, 2016.
- Lead pipe inventory: 6 lead and 4,074 unknown out of 4,277 service lines.
Check whether Maryville PWS 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 |
|---|---|---|---|---|
|
Interim Enhanced Surface Water Treatment Rule
Treatment technique failure
|
120 | Dec 1, 2025 |
Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
|
Yes |
|
Chlorite
Contaminant limit exceeded
Measured 1.1 mg/L, federal limit 1 mg/L (1.1 times the limit)
|
210 | Mar 1, 2024 | Resolved | No |
|
Chlorite
Contaminant limit exceeded
Measured 1.3 mg/L, federal limit 1 mg/L (1.3 times the limit)
|
210 | Feb 1, 2024 | Resolved | No |
|
Long Term 2 Enhanced Surface Water Treatment Rule
Treatment technique failure
|
120 | Dec 27, 2022 | Resolved | No |
Monitoring and reporting issues
Since October 2016Missed tests or reports, not contaminants found above a limit.
| Issue | Start date | Status |
|---|---|---|
|
Public Notice
OTHER
|
Apr 22, 2024 | Resolved |
|
Public Notice
OTHER
|
Apr 22, 2024 | Resolved |
|
Chlorite
Monitoring and reporting
|
Mar 1, 2024 | Resolved |
|
Chlorine dioxide
Monitoring and reporting
|
Feb 1, 2024 | Resolved |
|
Chlorite
Monitoring and reporting
|
Feb 1, 2024 | Resolved |
|
Chlorite
Monitoring and reporting
|
Nov 1, 2023 | Resolved |
|
Public Notice
OTHER
|
Mar 6, 2023 | Resolved |
|
Groundwater Rule
OTHER
|
Aug 27, 2022 | Resolved |
Full record since 1983
EPA's records for Maryville PWS go back to 1983. Before October 19, 2016 they list 16 health-based violations (15 resolved, 1 archived by EPA without a recorded fix) and 23 monitoring or reporting violations.
| Violations that began in | Health-based | Monitoring and reporting |
|---|---|---|
| 1980s | 1 | 22 |
| 2000s | 14 | 1 |
| 2010 to October 18, 2016 | 1 | 0 |
| 2020s | 4 | 8 |
Most recent health-based violation before October 19, 2016: Total Coliform, began May 2010, Resolved.
Show all 16 health-based violations before October 19, 2016
| Contaminant | Start date | Status |
|---|---|---|
|
Total Coliform
Contaminant limit exceeded
|
May 1, 2010 | Resolved |
|
Haloacetic Acids (HAA5)
Contaminant limit exceeded
Measured 70.11 µg/L, federal limit 60 µg/L (1.2 times the limit)
|
Oct 1, 2009 | Resolved |
|
Haloacetic Acids (HAA5)
Contaminant limit exceeded
Measured 63.88 µg/L, federal limit 60 µg/L (1.1 times the limit)
|
Jul 1, 2009 | Resolved |
|
CARBON, TOTAL
Treatment technique failure
|
Apr 1, 2009 | Resolved |
|
CARBON, TOTAL
Treatment technique failure
|
Jan 1, 2009 | Resolved |
|
CARBON, TOTAL
Treatment technique failure
|
Oct 1, 2008 | Resolved |
|
CARBON, TOTAL
Treatment technique failure
|
Jul 1, 2008 | Resolved |
|
CARBON, TOTAL
Treatment technique failure
|
Apr 1, 2008 | Resolved |
|
CARBON, TOTAL
Treatment technique failure
|
Jan 1, 2008 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
|
Jul 1, 2005 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
|
Apr 1, 2005 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
|
Jan 1, 2005 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
|
Oct 1, 2004 | Resolved |
|
Total Coliform (acute)
Contaminant limit exceeded
|
Jun 1, 2002 | Resolved |
|
Total Coliform
Contaminant limit exceeded
|
Jun 1, 2002 | Resolved |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
|
Jan 1, 1983 | Archived |
Enforcement actions
Missouri regulators issued 1 boil water order to Maryville PWS in 2002. The most recent was a boil water order in June 2002.
| Date | By | Action | Violations covered |
|---|---|---|---|
| Jun 14, 2002 | Missouri | Boil water order | 1 violation (1 health-based): Total Coliform |
What the violations mean
Chlorite
2 incidentsTest results for Chlorite were above the federal limit (a maximum contaminant level violation).
The utility had to notify customers about each of these violations.
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
Long Term 2 Enhanced Surface Water Treatment Rule
1 incidentThe system failed required surface water treatment or filtration standards
Untreated or inadequately treated surface water can contain bacteria and viruses
Where the water comes from
Maryville PWS draws water from 2 surface water intakes and 2 reservoirs. 1 other community water system buys water from Maryville PWS.
Community systems that buy water from it
- Nodaway County PWSD 1 Maryville, MO
Annual water quality report
Maryville PWS 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 Missouri.
Certified drinking water labs by state EPA guidance for private wells