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Transient Non-Community Water System · PWS AZ0412302

AZ State Pks Patagonia Lake

Operator location Nogales, Arizona - smaller served population (≤ 999) at 564 people served; 31 SDWIS violations on record from groundwater sources.

564
People served (this PWS)
31
EPA violations (this PWS)
1
Health-based (this PWS)
Untested
UCMR5 (this PWS)
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AZ State Pks Patagonia Lake standing, mid SDWIS violation third

564 people served (SDWIS) - smaller served population (≤ 999). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 3% is middle-third health share (≤ 23%). Population rank #27,158 of 29,740 among systems serving 500+.

The verdict

AZ State Pks Patagonia Lake lands in the middle third by violation volume (31), large enough for peer comparisons without matching the fleet's heaviest ledgers. Population served is smaller (564; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 3% (middle-third health share (≤ 23%)). No UCMR5 PFAS test appears for this system in this extract.

#27,158 of 29,740
Population · /systems
#381 of 413
Population · AZ
31
Total EPA violations on record
3%
Health-based (MCL / treatment failure)

Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.

System Details

System Type
Transient Non-Community
Owner Type
State
Connections
140
County
Santa Cruz
School/Daycare
No
MCL Violations
1
Monitoring Violations
27
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 12 2010
Nitrate MR 8 2013
Revised Total Coliform Rule RPT 2 2020
Coliform (TCR) MCL 1 2006
Selenium MR 1 1988
Cadmium MR 1 1988
Fluoride MR 1 1988
Arsenic MR 1 1985
Chromium MR 1 1988
Mercury MR 1 1988
Barium MR 1 1988

Violation Count vs. the National Corpus

AZ State Pks Patagonia Lake has 31 recorded EPA violations, 43% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 56% carry more. 3% of this system's own violations are health-based (1 of 31), and it ranks #27,158 of 29,740 by population served among that same cohort.

EPA violations vs. the national water-system corpus

Public water systems serving 500+ people (EPA SDWIS)

31 Lower than most fewer violations than 56% of 29,740 water systems

the national water-system corpus, bucketed by value

Each bar is a band; taller bars hold more water systems. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source EPA SDWIS · 2026-05-15

Population served record for AZ State Pks Patagonia Lake

EPA SDWIS lists 564 people served and 140 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.

Sources: EPA SDWIS · Arizona DEQ, Drinking Water Program

Nationwide peers

31 violations · 564 served: nearest cross-state SDWIS matches.

What to do with AZ State Pks Patagonia Lake

Use this system's EPA-reported record as a starting filter, not a final verdict.

  • See how every tracked system in Arizona compares on the same EPA violation measures. Arizona systems
  • Check whether PFAS was detected at this system under UCMR5 testing. PFAS guide
  • Find and compare another public water system by name or PWSID. Search systems

EPA SDWIS and UCMR5 figures are informational only, not a substitute for a certified lab test of your own tap water.

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