Public water system record
Mendota
Serves Mendota, LaSalle County, IL · 6,926 people served
Federal records show 3 health-based violations and 3 monitoring/reporting issues for Mendota in the last ten years. The most serious issue in this window was a resolved Haloacetic Acids (HAA5) violation.
System profile
- Health-based violations, last 10 years
- 3
- Resolved
- 3
- Unresolved
- 0
- Any acute record
- No
- Monitoring issues, last 10 years
- 3
Key facts
- Mendota draws water from 4 wells (1 of them for emergency, seasonal or other part-time use).
- Highest measured level in the last 10 years: Haloacetic Acids (HAA5), 0.089 mg/L, federal limit 0.06 mg/L (1.5 times the limit), 2020.
- Most recent formal enforcement: signed compliance agreement by Illinois, October 2006.
- Record on file since 1977, with 22 health-based violations before October 19, 2016.
- Lead pipe inventory: 34 lead and 1,315 unknown out of 2,781 service lines.
Check whether Mendota 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 |
|---|---|---|---|---|
|
Haloacetic Acids (HAA5)
Contaminant limit exceeded
Measured 0.084 mg/L, federal limit 0.06 mg/L (1.4 times the limit)
|
220 | Jan 1, 2021 | Resolved | No |
|
Haloacetic Acids (HAA5)
Contaminant limit exceeded
Measured 0.089 mg/L, federal limit 0.06 mg/L (1.5 times the limit)
|
220 | Oct 1, 2020 | Resolved | No |
|
Haloacetic Acids (HAA5)
Contaminant limit exceeded
Measured 0.082 mg/L, federal limit 0.06 mg/L (1.4 times the limit)
|
220 | Jul 1, 2020 | Resolved | No |
Monitoring and reporting issues
Since October 2016Missed tests or reports, not contaminants found above a limit.
| Issue | Start date | Status |
|---|---|---|
|
LEAD AND COPPER RULE REVISIONS
RPT
|
Jul 2, 2025 | Resolved |
|
Consumer Confidence Rule
OTHER
|
Jul 1, 2025 | Resolved |
|
Lead and Copper Rule
Monitoring and reporting
|
Jul 1, 2025 | Active |
Full record since 1977
EPA's records for Mendota go back to 1977. Before October 19, 2016 they list 22 health-based violations (21 resolved, 1 archived by EPA without a recorded fix) and 3 monitoring or reporting violations.
| Violations that began in | Health-based | Monitoring and reporting |
|---|---|---|
| 1970s | 0 | 1 |
| 1980s | 1 | 0 |
| 2000s | 21 | 2 |
| 2020s | 3 | 3 |
Most recent health-based violation before October 19, 2016: Combined Radium (-226 and -228), began January 2008, Resolved.
Show all 22 health-based violations before October 19, 2016
| Contaminant | Start date | Status |
|---|---|---|
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
Measured 6 pCi/L, federal limit 5 pCi/L (1.2 times the limit)
|
Jan 1, 2008 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
Measured 6 pCi/L, federal limit 5 pCi/L (1.2 times the limit)
|
Oct 1, 2007 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
Measured 8 pCi/L, federal limit 5 pCi/L (1.6 times the limit)
|
Jul 1, 2007 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
Measured 8 pCi/L, federal limit 5 pCi/L (1.6 times the limit)
|
Apr 1, 2007 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
Measured 8 pCi/L, federal limit 5 pCi/L (1.6 times the limit)
|
Jan 1, 2007 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
Measured 8 pCi/L, federal limit 5 pCi/L (1.6 times the limit)
|
Oct 1, 2006 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
Measured 8 pCi/L, federal limit 5 pCi/L (1.6 times the limit)
|
Jul 1, 2006 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
Measured 6 pCi/L, federal limit 5 pCi/L (1.2 times the limit)
|
Apr 1, 2006 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
|
Apr 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 |
|
Total Coliform
Contaminant limit exceeded
|
Jun 1, 2004 | Archived |
|
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 |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
|
Nov 3, 2000 | Resolved |
|
Combined Radium (-226 and -228)
Contaminant limit exceeded
|
Aug 23, 1985 | Resolved |
Enforcement actions
Illinois regulators took 3 formal enforcement actions against Mendota between 2001 and 2006. The most recent was a signed compliance agreement in October 2006.
| Date | By | Action | Violations covered |
|---|---|---|---|
| Oct 25, 2006 | Illinois | Signed compliance agreement | 8 violations (8 health-based): Combined Radium (-226 and -228) |
| Jan 21, 2004 | Illinois | Signed compliance agreement | 12 violations (12 health-based): Combined Radium (-226 and -228) |
| Dec 5, 2001 | Illinois | Signed compliance agreement | 3 violations (3 health-based): Combined Radium (-226 and -228) |
What the violations mean
Haloacetic Acids (HAA5)
3 incidentsHaloacetic acid byproducts exceeded the federal limit
Long-term exposure to HAAs may increase cancer risk
Where the water comes from
Mendota draws water from 4 wells (1 of them for emergency, seasonal or other part-time use). 1 other community water system and 1 smaller public system such as schools, businesses or campgrounds buy water from Mendota.
Community systems that buy water from it
- Mendota Estates MHP Peru, IL
Annual water quality report
Mendota 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