Community Water System · PWS IL1671250
Thayer
Operator location Thayer, Illinois - 25% of 93 violations are health-based (upper-third health share (> 23%)); surface water source; 721 served per SDWIS.
- 721
- People served (this PWS)
- 93
- EPA violations (this PWS)
- 23
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
Thayer standing, high SDWIS violation third
25% of 93 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 25% is upper-third health share (> 23%). Population rank #23,922 of 29,740 among systems serving 500+.
The verdict
Thayer sits in the upper third of the sitemap cohort by violation count (93), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is smaller (721; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 25% - most of this ledger is MCL or treatment-technique exceedance. No UCMR5 PFAS test appears for this system in this extract.
- #23,922 of 29,740
- Population · /systems
- #1,076 of 1,310
- Population · IL
- 93
- Total EPA violations on record
- 25%
- Health-based (MCL / treatment failure)
Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.
System Details
- System Type
- Community
- Owner Type
- Local
- Connections
- 364
- County
- Sangamon
- School/Daycare
- No
- MCL Violations
- 18
- Monitoring Violations
- 45
- Treatment Tech Violations
- 5
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Atrazine | MCL | 18 | 1994 |
| Coliform (TCR) | MR | 13 | 2013 |
| Lead and Copper Rule | MR | 12 | 2023 |
| Consumer Confidence Rule | Other | 8 | 2019 |
| Total Haloacetic Acids (HAA5) | MR | 8 | 2019 |
| Chloramine | MR | 6 | 2013 |
| TTHM | MR | 6 | 2019 |
| Interim Enhanced Surface Water Treatment Rule | TT | 5 | 2010 |
Violation Count vs. the National Corpus
Thayer has 93 recorded EPA violations, 72% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 28% carry more. 25% of this system's own violations are health-based (23 of 93), and it ranks #23,922 of 29,740 by population served among that same cohort.
EPA violations vs. the national water-system corpus
Public water systems serving 500+ people (EPA SDWIS)
93 Around the middle fewer violations than 28% of 29,740 water systems
the national water-system corpus, bucketed by value
Each bar is a band; taller bars hold more water systems. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source EPA SDWIS · 2026-05-15
Health-based violations on Thayer
23 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for IL1671250.
Sources: EPA SDWIS · Illinois EPA, Bureau of Water
Nationwide peers
93 violations · 721 served: nearest cross-state SDWIS matches.
Cross-state systems with comparable violation load
Nearest cross-state community systems (500+ served) by total SDWIS violations on record.
Cross-state systems with smaller service footprints
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Thayer
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in Illinois compares on the same EPA violation measures. Illinois systems
- Check whether PFAS was detected at this system under UCMR5 testing. PFAS guide
- Find and compare another public water system by name or PWSID. Search systems
EPA SDWIS and UCMR5 figures are informational only, not a substitute for a certified lab test of your own tap water.