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Community Water System · PWS IL1115145

Royal Oaks MHP

Operator location Chicago, Illinois - smaller served population (≤ 999) at 170 people served; 104 SDWIS violations on record from groundwater sources.

170
People served (this PWS)
104
EPA violations (this PWS)
13
Health-based (this PWS)
Untested
UCMR5 (this PWS)
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Royal Oaks MHP standing, high SDWIS violation third

170 people served (SDWIS) - smaller served population (≤ 999). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 13% is middle-third health share (≤ 23%).

The verdict

Royal Oaks MHP sits in the upper third of the sitemap cohort by violation count (104), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is smaller (170; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 13% (middle-third health share (≤ 23%)). No UCMR5 PFAS test appears for this system in this extract.

104
Total EPA violations on record
13%
Health-based (MCL / treatment failure)
170
People served by this PWS (SDWIS)
N/A
PFAS compounds detected (UCMR5)

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

System Details

System Type
Community
Owner Type
Private
Connections
65
County
McHenry
School/Daycare
No
MCL Violations
12
Monitoring Violations
53
Treatment Tech Violations
1

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 27 2013
Chlorine MR 16 2013
Coliform (TCR) MCL 12 2011
TTHM MR 4 2008
Total Haloacetic Acids (HAA5) MR 4 2008
Consumer Confidence Rule Other 3 2025
Lead and Copper Rule MR 2 2007
Lead and Copper Rule TT 1 1994

Violation Count vs. the National Corpus

Royal Oaks MHP has 104 recorded EPA violations, 74% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 26% carry more. 13% of this system's own violations are health-based (13 of 104), and it ranks unranked by population served among that same cohort.

EPA violations vs. the national water-system corpus

Public water systems serving 500+ people (EPA SDWIS)

104 Around the middle fewer violations than 26% 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 Royal Oaks MHP

EPA SDWIS lists 170 people served and 65 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.

Sources: EPA SDWIS · Illinois EPA, Bureau of Water

Nationwide peers

104 violations · 170 served: nearest cross-state SDWIS matches.

What to do with Royal Oaks MHP

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

  • See how every tracked system in Illinois compares on the same EPA violation measures. Illinois 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