Public water system · CA2000505
ActiveLupine Bass Lake
At a glance
Lupine Bass Lake (PWSID CA2000505) is an active transient non-community water system in Madera County, California. It reports serving 11,930 people through 18 service connections. Its primary water source is groundwater, and EPA lists it as owned by the federal government. Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in August 2020.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
11,930
Service connections
18
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Lupine Bass Lake compare with other water systems in Madera County?
By EPA's size categories, Lupine Bass Lake is a large system (10,001 to 100,000 people). Madera County has 202 active public water systems, and Lupine Bass Lake is the 3rd-largest of them by population served. Its population served is about 13 times the county average of 915 people per system, and accounts for 6.5% 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 Lupine Bass Lake is about 83 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 Lupine Bass Lake?
EPA lists Lupine Bass Lake 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 Lupine Bass Lake have drinking water violations?
Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in August 2020. The violations listed here began between January 2007 and August 2020. By type: 7 monitoring and reporting and 5 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (TCR) (7 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 |
|---|---|---|---|---|
| 2020-08-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, E. coli (RTCR) · code 1A | Revised Total Coliform Rulecode 8000 | Yes | Resolved |
| 2014-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2013-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitritecode 1041 | No | Resolved |
| 2010-04-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2009-07-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2009-04-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2009-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2008-12-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2007-09-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2007-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | 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.
Lupine Bass Lake: frequently asked questions
Who runs Lupine Bass Lake?
Lupine Bass Lake (PWSID CA2000505) 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 Lupine Bass Lake serve?
Lupine Bass Lake reports serving 11,930 people through 18 service connections in Madera County, California.
Where does Lupine Bass Lake 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 Lupine Bass Lake have any drinking water violations?
Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in August 2020. 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 Lupine Bass Lake'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, 5 are health-based, and the most recent began in August 2020. For current results, consult EPA ECHO, or the CA state drinking water program.
Where can I find Lupine Bass Lake's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Lupine Bass Lake 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 |
| 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 |
| Cal Am - Bass Lake | Madera | 4,527 | 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, “Lupine Bass Lake, PWSID CA2000505, California”, https://aquacensus.com/water-systems/california/lupine-bass-lake-ca2000505 (data as of October 1, 2026).