Public water system · IL1671250
ActiveThayer
At a glance
Thayer (PWSID IL1671250) is an active community water system in Sangamon County, Illinois. It reports serving 721 people through 364 service connections. Its primary water source is purchased surface water, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in October 2023.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
721
Service connections
364
Primary source
SWP
Purchased surface water
System type
CWS
Community water system
System record
How does Thayer compare with other water systems in Sangamon County?
By EPA's size categories, Thayer is a small system (501 to 3,300 people). Sangamon County has 43 active public water systems. Its population served is well below the county average of 4,245 people per system, and accounts for 0.4% of the 182,536 people reported by systems filed under the county. Across Illinois, the 3,872 active systems average 3,204 people each. Nationally, the average active community water system reports serving 6,703 people, so Thayer is well below that figure.
What does “community water system” mean?
A community water system serves at least 15 connections used by year-round residents, or regularly serves at least 25 year-round residents. Homes, apartments and mobile-home parks are served by these. Illinois has 1,773 active community water systems, 46% of the state's 3,872 active systems. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 619 Illinois systems (16%) list purchased surface water as their primary source.
Who owns and regulates Thayer?
EPA lists Thayer as owned by a local government. The IL state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 20 of the 43 active systems in Sangamon County (47%) are also owned by a local government.
Does Thayer have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in October 2023. The violations listed here began between July 2012 and October 2023. By type: 10 monitoring and reporting and 2 public notice, recordkeeping or other. The contaminant or rule involved most often is Lead and Copper Rule (3 of them). EPA lists 12 as resolved. Resolved means at least one resolving action is on record: the system returned to compliance, the rule no longer applies, or no further action was needed.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2023-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2020-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2019-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2019-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2019-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2019-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2018-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2018-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2013-04-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2013-04-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2013-04-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chloraminecode 1006 | No | Resolved |
| 2012-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Resolved |
The 12 most recent violations in EPA's records, newest first.Labels and codes come from EPA's SDWIS reference tables. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found. "Health-based" marks violations of a legal limit or required treatment.
Thayer: frequently asked questions
Who runs Thayer?
Thayer (PWSID IL1671250) is a community water system owned by a local government. It is regulated by the IL state drinking water program.
How many people does Thayer serve?
Thayer reports serving 721 people through 364 service connections in Sangamon County, Illinois.
Where does Thayer get its water?
EPA SDWIS lists this system's primary water source as purchased surface water. Purchased surface water means the system buys surface water from another public water system rather than drawing its own.
Does Thayer have any drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in October 2023. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found.
Is Thayer's water safe to drink?
AquaCensus shows EPA compliance records, not current water test results, so it cannot say whether the water is safe at a given moment. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in October 2023. For current results, consult the system's annual water quality report, EPA ECHO, or the IL state drinking water program.
Where can I find Thayer's water quality report?
As a community water system, Thayer must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1 each year, covering the previous calendar year. The system can provide a copy on request.
Other water systems in Sangamon County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Springfield | Sangamon | 117,444 | Community | Surface water |
| Chatham | Sangamon | 16,423 | Community | Purchased groundwater |
| Curran-Gardner Township PWD | Sangamon | 6,651 | Community | Groundwater |
| Williamsville | Sangamon | 6,198 | Community | Purchased surface water |
| Auburn | Sangamon | 4,574 | Community | Purchased surface water |
| Riverton | Sangamon | 4,279 | Community | Groundwater |
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About this data
Source: U.S. EPA Safe Drinking Water Information System (SDWIS) and SDWA violation records, via EPA ECHO, as published October 1, 2026 — AquaCensus refreshes it quarterly. See the methodology for how records are matched, cleaned and scored.
Cite as: AquaCensus, “Thayer, PWSID IL1671250, Illinois”, https://aquacensus.com/water-systems/illinois/thayer-il1671250 (data as of October 1, 2026).