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Non-Transient Non-Community Water System · PWS CA3500562

McAlpine Lake & Park

San Juan Bautista, California 95045 - drinking water served from groundwater sources to 111 people, tracked in EPA SDWIS and UCMR5.

111
People served
38
EPA violations
11
Health-based
Untested
UCMR5 result

The verdict

EPA records 38 drinking-water violations at McAlpine Lake & Park, 29% of them health-based - above the California per-system average.

38
Total EPA violations on record
29%
Health-based (MCL / treatment failure)
111
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: McAlpine Lake & Park

McAlpine Lake & Park is a private-owned non-transient non-community water system that delivers drinking water to 111 residents in San Juan Bautista, California (San Benito County) through 113 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 38 total violations for this system , of which 11 (29%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 26 monitoring and reporting violations are on file. The most recent violation on record dates to 2024.

The most frequently cited contaminant at this system is Coliform (TCR), recorded in 8 violations (MCL, health-based). This system has not yet been sampled under EPA's UCMR5 PFAS monitoring program, so no PFAS detection data is available here.

Across California, EPA tracks 7,249 public water systems serving 42,404,883 people, with 153,308 cumulative violations and 63,983 health-based violations on record. About 89% of systems in the state carry at least one violation, and state-wide the average per system is 21.1 violations. Statewide, 447 of 694 UCMR5-tested systems have reported PFAS detections (64.4%).

McAlpine Lake & Park's 38 violations sit above the California average.

All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.

Population Served
111
Total Violations
38
Health-Based Violations
11
Water Source
Groundwater

System Details

System Type
Non-Transient Non-Community
Owner Type
Private
Connections
113
County
San Benito
School/Daycare
No
MCL Violations
10
Monitoring Violations
26
Treatment Tech Violations
1

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MCL 8 2015
Nitrate MR 6 2003
Coliform (TCR) MR 6 2003
Total Haloacetic Acids (HAA5) MR 4 2013
TTHM MR 4 2013
Stage 2 Disinfectants and Disinfection Byproducts Rule MR 2 2013
Lead and Copper Rule MR 2 2018
Bromate MR 2 2013
Nitrate MCL 2 2002
LEAD AND COPPER RULE REVISIONS TT 1 2024
LEAD AND COPPER RULE REVISIONS RPT 1 2024

Verify This Water System

The figures above are aggregated from EPA's public databases. To verify the underlying records, or to file a complaint, request a Consumer Confidence Report, or check current monitoring status, go directly to the federal and state regulators that enforce the Safe Drinking Water Act for McAlpine Lake & Park.

Federal Source of Truth

EPA SDWIS, Federal Reports

EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:

View PWS ID CA3500562 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

California Drinking Water Authority

California State Water Resources Control Board, Division of Drinking Water is the primacy agency that licenses and inspects McAlpine Lake & Park under EPA-delegated authority.

Open CA regulator portal

Source: California State Water Resources Control Board, Division of Drinking Water

Violation Timeline

Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.

Year (latest) Contaminant Category Count EPA Record
2024 LEAD AND COPPER RULE REVISIONS TT 1 SDWIS / CA3500562 / 5200
2024 LEAD AND COPPER RULE REVISIONS RPT 1 SDWIS / CA3500562 / 5200
2018 Lead and Copper Rule MR 2 SDWIS / CA3500562 / 5000
2015 Coliform (TCR) MCL 8 SDWIS / CA3500562 / 3100
2013 Total Haloacetic Acids (HAA5) MR 4 SDWIS / CA3500562 / 2456
2013 TTHM MR 4 SDWIS / CA3500562 / 2950
2013 Stage 2 Disinfectants and Disinfection Byproducts Rule MR 2 SDWIS / CA3500562 / 0600
2013 Bromate MR 2 SDWIS / CA3500562 / 1011
2003 Nitrate MR 6 SDWIS / CA3500562 / 1040
2003 Coliform (TCR) MR 6 SDWIS / CA3500562 / 3100
2002 Nitrate MCL 2 SDWIS / CA3500562 / 1040

How McAlpine Lake & Park Compares

Cross-reference this system's record against state averages and the federal MCL framework for context.

Metric McAlpine Lake & Park California avg Federal benchmark
Total violations 38 21.1 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 11 8.8 Indicates a contaminant exceeded a federal MCL
PFAS detection None 64.4% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 111 5,850 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 7,249 regulated public water systems in California.

Federal MCL reference, Safe Drinking Water Act thresholds ▼
Contaminant Federal MCL / Action Level Note
Lead 0 mg/L (Action Level: 0.015 mg/L) Lead and Copper Rule treatment technique
Arsenic 0.010 mg/L (10 ppb) Health-based MCL since 2006
Total Coliform Treatment technique (RTCR) Indicator organism, monitoring trigger
PFOA / PFOS (PFAS) 4.0 ppt each (final 2024 rule) Compliance deadline 2029 (EPA proposed extending to 2031, not yet final as of May 2026)
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is McAlpine Lake & Park water safe to drink? ▼
McAlpine Lake & Park (PWS ID: CA3500562) has 38 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 111 people using Groundwater sources.
How many people does McAlpine Lake & Park serve? ▼
McAlpine Lake & Park serves 111 people in San Juan Bautista, California. It is a Private-owned system using Groundwater water sources with 113 service connections.
What type of violations does McAlpine Lake & Park have? ▼
McAlpine Lake & Park has 38 total violations: 11 health-based violations (MCL exceedances or treatment failures), 26 monitoring/reporting violations, and 1 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in McAlpine Lake & Park water? ▼
No PFAS testing data is available for McAlpine Lake & Park under the EPA's UCMR5 monitoring program.
What water source does McAlpine Lake & Park use? ▼
McAlpine Lake & Park uses Groundwater as its primary water source. It is classified as a Non-Transient Non-Community Water System, serving the same people for at least 6 months per year.
Where does this data come from? ▼
All data comes from the EPA Safe Drinking Water Information System (SDWIS) and the UCMR5 PFAS monitoring program. SDWIS tracks compliance for all public water systems regulated under the Safe Drinking Water Act.
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025. This data is provided for informational purposes only.

Read our methodology - how this data is sourced, computed, and verified.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater Editorial

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This system's figures are rendered directly from EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.