Public water system · CA2010501
ActiveNps-Devils Postpile
At a glance
Nps-Devils Postpile (PWSID CA2010501) is an active transient non-community water system in Madera County, California. It reports serving 1,220 people through 12 service connections. Its primary water source is groundwater, and EPA lists it as owned by the federal government. EPA's records list 4 violations for this system; 1 is health-based, and the most recent began in January 2012.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
1,220
Service connections
12
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Nps-Devils Postpile compare with other water systems in Madera County?
By EPA's size categories, Nps-Devils Postpile is a small system (501 to 3,300 people). Madera County has 202 active public water systems. Its population served is about 33% above the county average of 915 people per system, and accounts for 0.7% of the 184,760 people reported by systems filed under the county. Across California, the 7,479 active systems average 5,706 people each. Nationally, the average active transient non-community water system reports serving 144 people, so Nps-Devils Postpile is about 8.5 times that figure.
What does “transient non-community water system” mean?
A transient non-community water system serves places where people do not stay long, such as gas stations and campgrounds, and regularly serves at least 25 people a day for at least 60 days a year. California has 3,016 active transient non-community water systems, 40% of the state's 7,479 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 6,179 California systems (83%) list groundwater as their primary source.
Who owns and regulates Nps-Devils Postpile?
EPA lists Nps-Devils Postpile as owned by the federal government. The CA state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 11 of the 202 active systems in Madera County (5.4%) are also owned by the federal government.
Does Nps-Devils Postpile have drinking water violations?
EPA's records list 4 violations for this system; 1 is health-based, and the most recent began in January 2012. The violations listed here began between January 2000 and January 2012. By type: 3 monitoring and reporting and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Nitrate (3 of them). EPA lists 4 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 |
|---|---|---|---|---|
| 2012-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2008-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2006-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2000-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
All 4 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.
Nps-Devils Postpile: frequently asked questions
Who runs Nps-Devils Postpile?
Nps-Devils Postpile (PWSID CA2010501) is a transient non-community water system owned by the federal government. It is regulated by the CA state drinking water program.
How many people does Nps-Devils Postpile serve?
Nps-Devils Postpile reports serving 1,220 people through 12 service connections in Madera County, California.
Where does Nps-Devils Postpile 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 Nps-Devils Postpile have any drinking water violations?
EPA's records list 4 violations for this system; 1 is health-based, and the most recent began in January 2012. 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 Nps-Devils Postpile'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. EPA's records list 4 violations for this system; 1 is health-based, and the most recent began in January 2012. For current results, consult EPA ECHO, or the CA state drinking water program.
Where can I find Nps-Devils Postpile's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Nps-Devils Postpile is a transient non-community water system, so it is not required to publish one; like every public water system, it must notify the people it serves about violations under EPA's public notification rules.
Other water systems in Madera County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| City of Madera | Madera | 66,560 | Community | Groundwater |
| Chowchilla City Water Dept | Madera | 13,916 | Community | Groundwater |
| Lupine Bass Lake | Madera | 11,930 | Transient non-community | Groundwater |
| Madera Valley Water Company | Madera | 6,494 | Community | Groundwater |
| Riverstone/Rootcreek Water District | Madera | 5,507 | Community | Groundwater |
| Yosemite Spring Park Util Co | Madera | 5,300 | 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, “Nps-Devils Postpile, PWSID CA2010501, California”, https://aquacensus.com/water-systems/california/nps-devils-postpile-ca2010501 (data as of October 1, 2026).