Public water system record
Monmouth
Serves Monmouth, Warren County, IL · 8,902 people served
Federal records show 1 health-based violation and 1 monitoring/reporting issue for Monmouth in the last ten years. The most serious issue in this window was a resolved Combined Radium (-226 and -228) violation.
System profile
- Health-based violations, last 10 years
- 1
- Resolved
- 1
- Unresolved
- 0
- Any acute record
- No
- Monitoring issues, last 10 years
- 1
Key facts
- Monmouth draws water from 6 wells.
- Highest measured level in the last 10 years: Combined Radium (-226 and -228), 6 pCi/L, federal limit 5 pCi/L (1.2 times the limit), 2024.
- Most recent formal enforcement: signed compliance agreement by Illinois, February 2004.
- Record on file since 1977, with 28 health-based violations before October 19, 2016.
- Lead pipe inventory: 505 lead and 2,418 unknown out of 3,698 service lines.
Check whether Monmouth 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 |
|---|---|---|---|---|
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
Measured 6 pCi/L, federal limit 5 pCi/L (1.2 times the limit)
|
340 | Oct 1, 2024 | 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
|
Nov 28, 2024 | Resolved |
Full record since 1977
EPA's records for Monmouth go back to 1977. Before October 19, 2016 they list 28 health-based violations (25 resolved, 3 archived by EPA without a recorded fix) and 2 monitoring or reporting violations.
| Violations that began in | Health-based | Monitoring and reporting |
|---|---|---|
| 1970s | 0 | 1 |
| 1980s | 5 | 0 |
| 1990s | 5 | 1 |
| 2000s | 18 | 0 |
| 2020s | 1 | 1 |
Most recent health-based violation before October 19, 2016: Gross Alpha, Excl. Radon and U, began July 2005, Resolved.
Show all 28 health-based violations before October 19, 2016
| Contaminant | Start date | Status |
|---|---|---|
|
Gross Alpha, Excl. Radon and U
Contaminant limit exceeded
|
Jul 1, 2005 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
|
Jul 1, 2005 | Resolved |
|
Gross Alpha, Excl. Radon and U
Contaminant limit exceeded
|
Apr 1, 2005 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
|
Apr 1, 2005 | Resolved |
|
Gross Alpha, Excl. Radon and U
Contaminant limit exceeded
|
Jan 1, 2005 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
|
Jan 1, 2005 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
|
Oct 1, 2004 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
|
Jul 1, 2004 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
|
Apr 1, 2004 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
|
Jan 1, 2004 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
|
Oct 1, 2003 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
|
Jul 1, 2003 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
|
Apr 1, 2003 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
|
Jan 1, 2003 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
|
Oct 1, 2002 | Resolved |
|
Gross Alpha, Excl. Radon and U
Contaminant limit exceeded
|
Aug 1, 2002 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
|
Oct 1, 2001 | Resolved |
|
Total Coliform
Contaminant limit exceeded
|
Jun 1, 2001 | Archived |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
|
Oct 1, 1997 | Resolved |
|
Gross Alpha, Excl. Radon and U
Contaminant limit exceeded
|
Jul 12, 1995 | Resolved |
|
Total Coliform
Contaminant limit exceeded
|
Jul 1, 1994 | Archived |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
|
Sep 3, 1993 | Resolved |
|
Gross Alpha, Excl. Radon and U
Contaminant limit exceeded
|
May 1, 1990 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
|
Sep 1, 1988 | Resolved |
|
Gross Alpha, Excl. Radon and U
Contaminant limit exceeded
|
May 15, 1986 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
|
Sep 14, 1984 | Resolved |
|
Fluoride
Contaminant limit exceeded
|
May 1, 1983 | Resolved |
|
Fluoride
Contaminant limit exceeded
|
May 15, 1980 | Archived |
Enforcement actions
Illinois regulators took 2 formal enforcement actions against Monmouth between 2001 and 2004. The most recent was a signed compliance agreement in February 2004.
| Date | By | Action | Violations covered |
|---|---|---|---|
| Feb 17, 2004 | Illinois | Signed compliance agreement | 20 violations (20 health-based): Combined Radium (-226 and -228), Gross Alpha, Excl. Radon and U |
| Dec 10, 2001 | Illinois | Signed compliance agreement | 7 violations (7 health-based): Gross Alpha, Excl. Radon and U, Combined Radium (-226 and -228) |
What the violations mean
Combined Radium (-226 and -228)
1 incidentTest results for Combined Radium (-226 and -228) were above the federal limit (a maximum contaminant level violation).
The utility had to notify customers about this violation.
Where the water comes from
Monmouth draws water from 6 wells. 1 smaller public system such as schools, businesses or campgrounds buys water from Monmouth.
Annual water quality report
Monmouth 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 Illinois.
Certified drinking water labs by state EPA guidance for private wells