Community Water System · PWS MT0004368
Ryans Lot
Operator location Hermosa Beach, Montana - smaller served population (≤ 999) at 34 people served; 788 SDWIS violations on record from groundwater sources.
- 34
- People served (this PWS) Smaller third of systems
- 788
- EPA violations (this PWS) Upper third of systems
- 80
- Health-based (this PWS) Middle third by health-based share
- Untested
- UCMR5 (this PWS) No UCMR5 result
Ryans Lot standing, high SDWIS violation third
34 people served (SDWIS) - smaller served population (≤ 999). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 10% is middle-third health share (≤ 23%).
The verdict
Ryans Lot sits in the upper third of the sitemap cohort by violation count (788), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is smaller (34; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 10% (middle-third health share (≤ 23%)). No UCMR5 PFAS test appears for this system in this extract.
- 788
- Total EPA violations on record
- 10%
- Health-based (MCL / treatment failure)
- 34
- 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.
Based on EPA SDWIS violation history and UCMR5 PFAS testing only, not water taste, odor, infrastructure age, or contaminants outside the federally tracked set.
System Details
- System Type
- Community
- Owner Type
- Private
- Connections
- 15
- County
- Missoula
- School/Daycare
- No
- MCL Violations
- 64
- Monitoring Violations
- 677
- Treatment Tech Violations
- 16
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MCL | 64 | 2009 |
| Groundwater Rule | MR | 29 | 2022 |
| Consumer Confidence Rule | Other | 20 | 2025 |
| Benzene | MR | 18 | 2005 |
| Toluene | MR | 18 | 2005 |
| Ethylbenzene | MR | 18 | 2005 |
| Styrene | MR | 18 | 2005 |
| 1,2,4-Trichlorobenzene | MR | 18 | 2005 |
| Xylenes, Total | MR | 18 | 2005 |
| o-Dichlorobenzene | MR | 18 | 2005 |
| 1,2-Dichloroethane | MR | 18 | 2005 |
| 1,1,2-Trichloroethane | MR | 18 | 2005 |
| DICHLOROMETHANE | MR | 18 | 2005 |
| p-Dichlorobenzene | MR | 18 | 2005 |
| Vinyl chloride | MR | 18 | 2005 |
| 1,1-Dichloroethylene | MR | 18 | 2005 |
| trans-1,2-Dichloroethylene | MR | 18 | 2005 |
| 1,1,1-Trichloroethane | MR | 18 | 2005 |
| 1,2-Dichloropropane | MR | 18 | 2005 |
| Tetrachloroethylene | MR | 18 | 2005 |
| cis-1,2-Dichloroethylene | MR | 18 | 2005 |
| Trichloroethylene | MR | 18 | 2005 |
| CHLOROBENZENE | MR | 18 | 2005 |
| Carbon tetrachloride | MR | 18 | 2005 |
| Groundwater Rule | TT | 16 | 2023 |
| Lead and Copper Rule | MR | 12 | 2014 |
| TTHM | MR | 10 | 2017 |
| Total Haloacetic Acids (HAA5) | MR | 10 | 2017 |
| Groundwater Rule | Other | 8 | 2023 |
| Coliform (TCR) | MR | 7 | 2006 |
Violation Count vs. the National Corpus
Ryans Lot has 788 recorded EPA violations, 98% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 2% carry more. 10% of this system's own violations are health-based (80 of 788), 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)
788 Higher than most more violations than 98% 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
How many violations vs. how serious, among peer systems
Ryans Lot plotted against 29 peer public water systems (500+ people served), by total violation count (x) and the share of those violations that are health-based (y). The crosshair sits at this sample's own median on each axis. A high violation count does not automatically mean a serious record: most monitoring and reporting violations are minor, not health-based.
Violation volume vs. health-based share
Population served record for Ryans Lot
EPA SDWIS lists 34 people served and 15 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.
Sources: EPA SDWIS
Nationwide peers
788 violations · 34 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.
What to do with Ryans Lot
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in Montana compares on the same EPA violation measures. Montana 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.
Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.