Public water system · MO1010432
ActiveKnob Noster Pws
At a glance
Knob Noster Pws (PWSID MO1010432) is an active community water system in Johnson County, Missouri. It reports serving 2,863 people through 1,347 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in March 2023.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
2,863
Service connections
1,347
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Knob Noster Pws compare with other water systems in Johnson County?
By EPA's size categories, Knob Noster Pws is a small system (501 to 3,300 people). Johnson County has 15 active public water systems, and Knob Noster Pws is the 6th-largest of them by population served. Its population served is about 26% below the county average of 3,883 people per system, and accounts for 4.9% of the 58,237 people reported by systems filed under the county. Across Missouri, the 2,943 active systems average 2,049 people each. Nationally, the average active community water system reports serving 6,703 people, so Knob Noster Pws is about 57% 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. Missouri has 1,612 active community water systems, 55% of the state's 2,943 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 2,521 Missouri systems (86%) list groundwater as their primary source.
Who owns and regulates Knob Noster Pws?
EPA lists Knob Noster Pws as owned by a local government. The MO state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 10 of the 15 active systems in Johnson County (67%) are also owned by a local government.
Does Knob Noster Pws have drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in March 2023. The violations listed here began between January 1994 and March 2023. By type: 10 monitoring and reporting, 1 monitoring and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Nitrate-Nitrite (2 of them). EPA lists 11 as resolved and 1 as archived. 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. Archived means the violation was not marked resolved but is more than five years past the end of the noncompliance period, so it no longer counts toward current compliance status.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2023-03-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2004-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2004-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitrate-Nitritecode 1038 | No | Resolved |
| 1999-06-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Archived |
| 1994-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,2,4-Trichlorobenzenecode 2378 | No | Resolved |
| 1994-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | p-Dichlorobenzenecode 2969 | No | Resolved |
| 1994-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Xylenes, Totalcode 2955 | No | Resolved |
| 1994-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Dichloromethanecode 2964 | No | Resolved |
| 1994-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitrate-Nitritecode 1038 | No | Resolved |
| 1994-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Styrenecode 2996 | No | Resolved |
| 1994-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Chlorobenzenecode 2989 | No | Resolved |
| 1994-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,1,2-Trichloroethanecode 2985 | 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.
Knob Noster Pws: frequently asked questions
Who runs Knob Noster Pws?
Knob Noster Pws (PWSID MO1010432) is a community water system owned by a local government. It is regulated by the MO state drinking water program.
How many people does Knob Noster Pws serve?
Knob Noster Pws reports serving 2,863 people through 1,347 service connections in Johnson County, Missouri.
Where does Knob Noster Pws get its water?
EPA SDWIS lists this system's primary water source as groundwater. Groundwater means the system draws its water from wells or springs fed by underground aquifers.
Does Knob Noster Pws have any drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in March 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 Knob Noster Pws' 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, one is health-based, and the most recent began in March 2023. For current results, consult the system's annual water quality report, EPA ECHO, or the MO state drinking water program.
Where can I find Knob Noster Pws' water quality report?
As a community water system, Knob Noster Pws 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 Johnson County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Mo American Warrensburg | Johnson | 18,500 | Community | Groundwater |
| Johnson County Pwsd 2 | Johnson | 12,490 | Community | Groundwater |
| Whiteman Air Base | Johnson | 10,106 | Community | Groundwater |
| Johnson County Pwsd 3 | Johnson | 4,700 | Community | Groundwater |
| Johnson County Pwsd 1 | Johnson | 3,730 | Community | Groundwater |
| Holden Pws | Johnson | 2,683 | Community | Surface water |
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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, “Knob Noster Pws, PWSID MO1010432, Missouri”, https://aquacensus.com/water-systems/missouri/knob-noster-pws-mo1010432 (data as of October 1, 2026).