Community Water System · PWS LA1029006
Lake St John Waterworks District 1
Operator location Ferriday, Louisiana - 90% of 731 violations are health-based (upper-third health share (> 23%)); groundwater source; 2,067 served per SDWIS.
- 2,067
- People served (this PWS)
- 731
- EPA violations (this PWS)
- 656
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
Lake St John Waterworks District 1 standing, high SDWIS violation third
90% of 731 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 90% is upper-third health share (> 23%). Population rank #13,312 of 29,740 among systems serving 500+.
The verdict
Lake St John Waterworks District 1 sits in the upper third of the sitemap cohort by violation count (731), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is mid-pack at 2,067 (mid served population (≤ 3,309)). Health-based share is 90% - most of this ledger is MCL or treatment-technique exceedance. No UCMR5 PFAS test appears for this system in this extract.
- #13,312 of 29,740
- Population · /systems
- #354 of 707
- Population · LA
- 731
- Total EPA violations on record
- 90%
- 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
- Community
- Owner Type
- Local
- Connections
- 689
- County
- Concordia Parish
- School/Daycare
- No
- MCL Violations
- 652
- Monitoring Violations
- 56
- Treatment Tech Violations
- 4
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Total Haloacetic Acids (HAA5) | MCL | 419 | 2023 |
| TTHM | MCL | 233 | 2023 |
| TTHM | MR | 25 | 2015 |
| Total Haloacetic Acids (HAA5) | MR | 25 | 2015 |
| Consumer Confidence Rule | Other | 7 | 2017 |
| Coliform (TCR) | MR | 6 | 2006 |
| Public Notice | Other | 4 | 2022 |
| Groundwater Rule | TT | 4 | 2021 |
Violation Count vs. the National Corpus
Lake St John Waterworks District 1 has 731 recorded EPA violations, 98% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 2% carry more. 90% of this system's own violations are health-based (656 of 731), and it ranks #13,312 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)
731 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
Health-based violations on Lake St John Waterworks District 1
656 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for LA1029006.
Sources: EPA SDWIS
Nationwide peers
731 violations · 2,067 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.
Cross-state systems near this population served
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Lake St John Waterworks District 1
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in Louisiana compares on the same EPA violation measures. Louisiana 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.