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Community Water System · PWS MD0050004

Jonestown Water System

Operator location Denton, Maryland - smaller served population (≤ 999) at 150 people served; 174 SDWIS violations on record from groundwater sources.

150
People served (this PWS)
174
EPA violations (this PWS)
15
Health-based (this PWS)
Untested
UCMR5 (this PWS)
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Jonestown Water System standing, high SDWIS violation third

150 people served (SDWIS) - smaller served population (≤ 999). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 9% is middle-third health share (≤ 23%).

The verdict

Jonestown Water System sits in the upper third of the sitemap cohort by violation count (174), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is smaller (150; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 9% (middle-third health share (≤ 23%)). No UCMR5 PFAS test appears for this system in this extract.

174
Total EPA violations on record
9%
Health-based (MCL / treatment failure)
150
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
56
County
Caroline
School/Daycare
No
MCL Violations
15
Monitoring Violations
141
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 100 2009
Lead and Copper Rule MR 16 2021
Nitrate MR 13 2009
Coliform (TCR) MCL 11 2005
Consumer Confidence Rule Other 11 2012
TTHM MR 4 2015
Total Haloacetic Acids (HAA5) MR 4 2015
Fluoride MR 4 2018
Nitrate MCL 4 1988
LEAD AND COPPER RULE REVISIONS RPT 1 2025

Violation Count vs. the National Corpus

Jonestown Water System has 174 recorded EPA violations, 83% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 17% carry more. 9% of this system's own violations are health-based (15 of 174), 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)

174 Higher than most more violations than 83% 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 Jonestown Water System

EPA SDWIS lists 150 people served and 56 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.

Sources: EPA SDWIS

Nationwide peers

174 violations · 150 served: nearest cross-state SDWIS matches.

Cross-state systems with comparable violation load

Nearest cross-state community systems (500+ served) by total SDWIS violations on record.

4 peers

What to do with Jonestown Water System

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

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